019031   Goel S;Bajaj S;Amanpreet Kaur (NO, , ) : Design of booth encoded multi-modulus {2N-1, 2N, 2N+1} RNS multiplier. J VLSI Des Tool Technol 2016, 6(3), 7-14.

Multiplication, a very important arithmetic operation, is finding a great use these days in various applications (especially DSP, multimedia and image processing). Due to advances in technology and increasing needs for high speed calculations, it has become really necessary and important to design a fast efficient multiplier. A productive method to speed up the multiplication is reduction in the Partial Product (PP) array. In this paper the design of 8, 16 and 32 bit RNS multiplier based on Radix-4 Booth encoding is presented. The results of simple Booth multiplier are compared to a Booth encoded Residue Number System (RNS) multiplier. A significant improvement in terms of speed and area utilization is observed when Booth is applied to RNS. Pipelining has been incorporated in the architectures to boost the speed further. The designs are described in Verilog HDL, simulated and synthesized on Xilinx 14.5, targeted on Spartan 3E FPGA device.

019030   Ghosh D (Physical and Materials Chemistry Div, CSIR-National Chemical Lab, Pune-411 008, Email: debashree.ghosh@ncl.res.in) : Multiscale modelling: Hybrid quantum mechanics/molecular mechanics as an example and some recent developments. Curr Sci 2017, 112(7), 1455-62.

Most of the physical phenomena are multiscale in nature and therefore, to depict it properly one requires multiscale modelling techniques, i.e. physical models that are accurate over multiple length and time scales. The seminal work by Warshel and Levitt marks the beginning of hybrid quantum mechanics/molecular mechanics (QM/MM) method as a successful strategy towards the understanding of chemistry and physics in condensed phases and especially in biological systems. Recently, these methods have been extended to problems such as light-matter interaction, where the QM sub-system is excited from the ground to the excited states. The MM environment provides a field that changes the potential energy landscape of both the ground and excited states in a distinctly different way. In this review, we discuss the general strategy of multiscale modelling with emphasis on hybrid QM/MM and the recent developments in excited state QM/MM methods.

5 illus, 35 ref

019029   Gautam S;Sharma P (NO, , ) : Area efficient layout design of two bit magnitude comparator using novel strategy. J VLSI Des Tool Technol 2016, 6(3), 1-6.

The development of digital circuits, digital signal processors and other data processing integrated circuits, comparators are challenged by large area consumption. Comparator is most basic and fundamental component that performs comparison operation. This paper proposes a new approach to design an area efficient two bit magnitude comparator. Comparision is done on the grounds of area and power consumed between circuit designed by novel strategy and preexisting CMOS technique. The novel technique described in this paper is found to be effective and efficient to reduce the chip area.

019028   Da Silva A N;Elzinga D (NO, , UNECE Secretariat, Ganeva) : Role of thermal power plants in select electricity markets. Indian J Pwr River Valley Dev 2016, 66(11-12), 153-6.

7 illus, 2 ref

019027   Chunn A;Sarin R K (NO, , ) : Design of low power resistor less flash ADC for UWB receiver applications. J VLSI Des Tool Technol 2016, 6(3), 71-87.

In this paper, two designs of flash analog to digital converters (ADCs) based on threshold inverter quantization (TIQ) technique are presented. The parallel threshold inverter quantization (PTIQ) flash ADC exploits the advantage of reduction in capacitance and power consumption if the transistors are placed in parallel. Another design called low voltage tunable body bias (LVTBB) PTIQ ADC operates at near threshold voltage level to minimize the power consumption. The PTIQ and LVTBB ADC designs attain Figure of merit of 0.09625 picoJoule/conversion (pJ/conv) and 0.06 pJ/conv respectively which is comparable to the existing state of art ADCs.

019026   Budinsky V (NO, UNECE, Geneva) : Role of coal plants in the world of renewables. Indian J Pwr River Valley Dev 2016, 66(11-12), 157-8.

6 ref

019025   Biswas D K;Choudhury A (NO, MIT, Bishunpur, Bankura, West Bengal) : Pollution management with techno-economical evaluation for coke based and cokeless furnaces concerning melting and casting of brass and bell metal. J Metall Mater Sci 2016, 58(4), 201-11.

India is a very important global player in the casting sector not only of cast iron but also of non-ferrous sector such as brass and bell metal. Melting furnaces of these are mainly coke based. There is also a growing awareness of pollution control levels in the country in recent times and this is a perceived as a threat to the existence of these small scale foundries including melting unit for casting for brass and bell metals scattered in various parts of the country. Attempt has been made to carry out research and development work on developing various modules eco-friendly furnaces concerning melting and of brass and bell metal casting/product. This paper also discusses technoeconomical aspect of the mentioned coke based and coke less furnaces concerning brass and bell metal product.

019024   Bhaskar P C;Gosavi P S (NO, , ) : Development of system for speech enhancement using combinational adaptive LMS on reconfigurable platform. J VLSI Des Tool Technol 2016, 6(3), 28-34.

Low cost and robustness makes the least mean square (LMS) algorithm most popular. Improved adaptive filter performance can be obtained by combinational approach. In this paper, for speech enhancement, we used one of such approaches known as 'filter combination'. As our simulation results show, Fixed-Sign LMS algorithm overcome other algorithms in terms of SNR and mean square error.

019023   Barman B (Electronics and Communication Engineering Dep, Kalyani Government Engineering College, Kalyani, Nadia) : Analysis and recognition of facial image by eigenface approach. Indian Sci Cruiser 2017, 31(1), 51-5.

In this paper, algorithm is developed based on eigenface algorithm to recognize facial image. After implementing the algorithm a reference image identified from a predefined facial image dataset. In preprocessing stage the images are resized to a consistent size. The performance of algorithm is analyzed by using pose and size of training dataset. It is seen from the result that robustness of the eigenface algorithm is good.

5 illus, 11 ref

019022   Bala P;Vinod Kumar;Mehra R (Applied Sciences, Humanities and Management Dep, Beant College of Engineering and Technology, Gurdaspur, Punjab, Email: pankajbala.nitj@gmail.com) : Measurement of radon exhalation rate in various building materials and soil samples. J Earth Syst Sci 2017, 126(2), 1-8.

Indoor radon is considered as one of the potential dangerous radioactive elements. Common building materials and soil are the major source of this radon gas in the indoor environment. In the present study, the measurement of radon exhalation rate in the soil and building material samples of Una and Hamirpur districts of Himachal Pradesh has been done with solid state alpha track detectors, LR-115 type-II plastic track detectors. The radon exhalation rate for the soil samples varies from 39.1 to 91.2 mBq kg^-1 h^-1 with a mean value 59.7 mBq kg^-1 h^-1. Also the radium concentration of the studied area is found and it varies from 30.6 to 51.9 Bq kg^-1 with a mean value 41.6 Bq kg^-1. The exhalation rate for the building material samples varies from 40.72 (sandstone) to 81.40 mBq kg^-1 h^-1 (granite) with a mean value of 59.94 mBq kg^-1 h^-1.

4 illus, 2 tables, 27 ref

019021   Anderla A;Sladojevic S;Delso G;Culibrk D; Mirkovic M;Stefanovic D (Industrial Engineering and Management Dep, Faculty of Technical Sciences, Novi Sad Univ, Trg Dositeja Obradovica 6, 21000, Novi Sad, Serbia, Email: darkoste@uns.ac.rs) : - 257 - Suppression of metal artefacts in CT using virtual singorams and corresponding MR images. Curr Sci 2017, 112(7), 1505-11.

Medical imaging is invaluable when it comes to gaining insight into the human body. As is well known, medical images need to deal with artefacts. This article presents a modern procedure for metal artifact reduction in computed tomography, which relies on additional information extracted from corresponding magnetic resonance images. We conducted a simulation study so as to compare the resulting images with those corrected, using the baseline linear interpolation method. The outcome indicates that the proposed method incomparably outperforms the baseline and reduces metal artefacts, improving the quality of images, which can be later used in a clinical setting.

4 illus, 24 ref

019020   Anand A K;Nageswaran K;Vinod Kumar;Saxena A (R&D Centre for Iron & Steel, Steel Authority of India Ltd., Ranchi, Jharkhand-834 002, Email: atul-saxena@sail-rdcis.com) : Hot deformation studies on 2.7% si steel using gleeble thermo-mechanical simulator. J Metall Mater Sci 2016, 58(4), 251-8.

Uni-axial hot compression tests were conducted at different temperatures (1173-1423 K) and at strain rates of 0.1, 1, 10 and 100/s using Thermo-mechanical Simulator (Gleeble-350°C System) on a 2.7% Si electrical steel to understand the hot workability issues associated with this steel during hot rolling. The flow curves obtained revealed dynamic recovery as the predominant softening mechanism at majority of hot deformation conditions except at lower temperature and high strain rate where work hardening was observed. However, the work hardening was not very prominent due to ferrite structure throughout the hot deformation temperature range established by Thermo-Calc software. Small amount of cementite (pearlite) transformed from austenite along prior ferrite grain was observed due to presence of carbon in excess of 0.02. Strain rate sensitivity varied within a narrow range of 0.18-0.21 with rising tendency with an increase in temperature.

019019   Ambrisko L;Marasova D;Cehlar M (Faculty of Mining, Ecology, Process Control and Geotechnology, Technical Univ of Kosice,, Park Komenskeho 14, 043 84 Kosice, Slovak Republic, Email: lubomir.ambrisko@tuke.sk) : Investigating the tension load of rubber composites by impact dynamic testing. Bull Mater Sci 2017, 40(2), 281-7.

This work deals with establishing the tension load by impact dynamic testing of rubber composite conveyor belts. The value of tension load affects the shape of the used impactor and use of a support system as well as the weight of the ram and the impact height. An increase in the allowable stress when the belt is tensioned was examined during the test, to determine the effect of impact on the tension load. The obtained values of tension load are assessed using basic mathematical and statistical methods. Using the Design of Experiments method, factors that significantly affect the value of the tension load are identified.

7 illus, 6 tables, 20 ref

018160   Srinivasan V;Khandekar S (Mechanical Engineering Dep, Indian Institute of Technology, Kanpur, Kanpur-208 016, Email: samkhan@iitk.ac.in) : Thermo-hydrodynamic transport phenomena in partially wetting liquid plugs moving inside micro-channels. Sadhana 2017, 42(4), 607-24.

Single-phase as well as two-phase fluid flows inside mini/micro-channels and capillary tubes are of practical importance in many miniaturized engineering systems. While several issues related to single-phase transport are fairly well understood, two-phase systems still pose challenges for engineering design. The presence of gas-liquid interfaces, dominance of surface forces, moving contact lines, wettability, dynamic contact angle hysteresis and flow in confined geometries are some of the unique features of two-phase systems, which manifest into complex transport phenomena. While Taylor plug/bubble flow is a fairly common flow pattern in several micro-fluidic devices operating at low Bond number, the ensuing transport characteristics are complex and still not fully discerned. This review paper aims at highlighting the nuances and features of a unit cell of a Taylor plug flow, especially focusing on partially wetting systems, which are more common in engineering applications. Emphasis is given to a 'unit cell' flow system consisting of an isolated liquid Taylor plug with adjacent gas phase, confined in a capillary tube. Such a seemingly simple flow condition poses considerable challenges for discerning and modelling local thermo-hydrodynamic transport coefficients. Relevant background information and fundamentals are carefully scrutinized while summarizing the state-of-the-art. The role of wettability and dissipation near the contact line is highlighted via available experimental and simulation results. Local momentum and heat transfer exchange processes during the motion of an isolated plug of partially wetting liquid moving inside a capillary tube are delineated.

12 illus, 91 ref

018159   Shivani V;Devashrayee N M (NO, , ) : Analysis and characterization of different topologies of dynamic latch based CMOS comparators for delay, offset and power. J VLSI Des Tool Technol 2016, 6(2), 86-98.

This paper presents the analysis and characterization of various topologies of dynamic latch based complementary metal oxide semiconductor (CMOS) - 312 - comparator. Various comparator topologies like resistor divider comparator (R.DC). differential pair comparator (DPC), double-tail dynamic latched comparator (DTDLC), energy efficient two stage comparator (ETWC) and two-stage dynamic comparator (TSDL) are analyzed and compared for various performance parameters. Besides zero static power consumption, resistor divider comparator has high offset voltage and it depends on the input differential common mode voltage. Differential pair comparator having less delay and less offset voltage compared to resistor divider comparator, but requires more voltage headroom. To overcome the drawbacks of differential comparator, double tail dynamic latch comparator can be used, but at cost of low speed and high power consumption. For low offset voltage (high resolution) applications, Two-stage dynamic comparator is preferred. This paper provides analysis and characterization review about a variety of traditional dynamic latched comparator designs - in terms of delay power, area, power delay product and input, referred offset voltage in HSP1CE simulation tool using 90nm PTM technology.

018158   Shibe V;Chawla V (Mechanical Engineering Dep, IKG Punjab Univ, Kapurthala-144 603, Email: shibevineet@gmail.com) : Enhancement in wear resistance by depositing Fe-C-Cr based hardfacing alloys on ASTM A36 steel. J Metall Mater Sci 2017, 59(1), 1-9.

Hardfacing is a surface modification technique mostly utilized for the deposition of superior and hard materials on the surface of a substrate with the help of some suitable welding process. This technique is commonly used for improving the desirable surface characteristics, for example, erosion resistance, corrosion resistance, etc. of several engineering parts. In the present investigation, three different types of Fe-C-Cr based hardfacing alloys were deposited on the surface of ASTM A36 steel by using manual metal arc welding process in order to enhance its wear resistance. Sliding wear behavior of bare ASTM A36 steel specimens and hardfaced ASTM A36 steel samples were studied on a pin-on-disc wear tester. It was observed that the sliding wear behavior and performance of all the hardfaced specimens was found to be better than that of the bare ASTM A36 steel samples. The effect of the different hardfacings on the wear characteristics, behavior, performance and the extent of wear on ASTM A36 steel were thoroughly examined. The effect of varying the percentage composition of chromium from 23% to 33% and carbon from 3.5% to 4.5% in the different Fe-C-Cr based hardfacing electrodes on the resultant microstructure as well as the wear behavior of the deposited layers was studied. The comparison of cumulative wear rate (in Bowden) of all the hardfaced specimens with that of the bare ASTM A36 samples exhibited a considerable advancement in the wear resistance imparted by Fe-C-Cr based hardfacings over the ASTM A36 steel.

018157   Sharma S;Nangia R;Shukla N K (NO, , ) : Design and RTL implementation fro AHBAPBbridge on SOC. J VLSI Des Tool Technol 2016, 6(2), 44-52.

The focus of this research is to design and implement an interconnection protocol with 32-bit read/write data which operates on AMBA AHB-APB bridge. With (he advent of scaling technology, embedded system focuses more on low-power dissipation and SoCs. Hence processors and routing protocols which focus on low-power design by ARM have gained popularity. In high-speed communication modules, the protocol works efficiently but has limitations with device operating at low speed. AHB-APB bridge standard can be used to alleviate this issue. While performing any read/write operation AHB must wait for the acknowledgement signal from APB. APB transactions are converted in to AHB. In addition of these features an error bit generates in case of any data mismatching during the data transfer between AHB to APB. Error bit becomes 1 if there is any mismatch in data, else, it becomes 0. AMBA AHB-APB is designed with the help of Verilog and its synthesis results in a total hierarchy power consumption of 0.041 mW, and leakage power 0.036 mW and minimum data path delay is 5.690 ns, timing and functional simulation modeling is done using Xilinx simulator 14.7, Chip scope pro.

018156   Sharma S K;Balwinder Raj;Khosla M (NO, , ) : Comparative analysis of mosfet, CNTFET and NWFET for high performance VLSI circuit design. J VLSI Des Tool Technol 2016, 6(2), 19-32.

Nanowires are inimitable materials for considering phenomenon in nanoscale regime. Nanowires development exhibits ample of applications by controlling their, structure, composition as well as their electrical properties. This paper review diverse types of nanowires, nanowire field-effect transistor (NWFET) structure and their comparison with novel devices. Firstly, this paper describes different types of nanowires ami nanowire heterostnicture that shows nanowire heterostructures eliminates various factors that limit the performance of homogeneous nanowire devices. Secondly, if introduces the basic NWFET and evaluates the performance comparison with different devices such as SGMOSFET, DGMOSFET and CNTFET. In nanometer regime, the quantum capacitance of FET devices decides the gate capacitance. CNTFET and NWFET have appreciable characteristics to reduce the gate capacitance by reducing the oxide thickness in deep nanometer regime, which is not. attainable to get in SGMOSFET and DGMOSFET. It is also seen that NWFETs and CNTFETs are considered as the most potential devices, due to their process compatibility with planar CMOS, small-off-leakage current and high-on-current.

018155   Sharma S;Goen A (NO, , ) : Review on digital filter design using artifical neural network. J Commun Engng Syst 2016, 6(2), 9-15.

This paper provide a survey report on designing Digital FIR filters with the help of Artificial neural network proposed by many researchers who gives a better results and easy way to design a filter. It includes types of filters, window techniques, artificial neural network, comparative analysis of various existing work. This paper gives a better way to analyze various techniques used to design FIR filters. This survey report provides the performance analysis of many researchers work.

^iia

018154   Sharma A;Singh G (NO, , ) : New TGC-differential input stage to modify dynamic comparator. J VLSI Des Tool Technol 2016, 6(2), 74-85.

As the technology - 310 - rapidly scaling down the escalating demand for higher accuracy is putting a heavy pressure to find ways to get rid of one of the major issues among present day dynamic comparators i.e. random offset voltage generation. A number of offset calibration techniques have been presented to resolve this issue. It has become an important concern to analyze these techniques for scaled down technology Nodes to cop up with modern day dynamic latched comparators. In this paper: the input stage of comparator is modified for offset minimization and a better high frequency response. The proposed topology is verified by simulating in 'Synopsys Custom-designer' environment using 32/28 nm-integrated technology node. The simulation results shows improvement in random offset generation and delay for the common mode range of 0.6 V and low voltage supply 0f 0.8 V with the capability of detecting input voltage difference up to 0.5 mV over some of the recent works. The structure operates at a higher speed with a delay reduction from 113 ps to 46 ps at approximately the same energy dissipation of 50 μW/GHz at a higher frequency of 4 GHz. The results obtained from 100 samples of transient 'Monte-Carlo simulations' shows minimization in offset generation with 1-sigma input referenced offset of 0.38 mV at the latch stage without any digital calibration schemes saving large area.

018153   Shah V;Dekhatwala A;Banerjee J;Patra A K (Mechanical Engineering Dep, Sardar Vallabhbhai National Institute of Technology, Surat-395 007, Email: jbaner@med.svnit.ac.in) : Analysis of dispersion of heated effluent from power plant: A case study. Sadhana 2017, 42(4), 557-74.

Thermal dispersion of heated effluent in a lake near nuclear power plant is analysed. Lake Bathymetry is established by data collection at a pre-planned matrix of sample points in the lake. Three-dimensional geometric model of the lake is developed based on the geometric data collected, using a high accuracy GPS and a dead weight based depth meter at respective sample points of the lake matrix. A turbine type digital flow meter is used to measure the velocities at the intake and blow down points of the lake. Numerical analysis of flow and thermal dispersion is carried out using PLIC-VOF two-phase model with the two-equation k-epsilon model for turbulence closure. Numerical results for varying flow and blow down temperature conditions and wind speed are studied. It is observed that the thermal gradients are steeper in the curved area near the blowdown point. Small increase in main inlet (inlet II) velocity suppresses the dispersion of high-temperature contours significantly. Thermal discharge and dispersed temperature is monitored using temperature sensor mounted floating buoy at various locations in the lake. It is established that the thermal dispersion is influenced by wind velocity and the presence of water hyacinth in the lake.

23 illus, 1 table, 28 ref

018152   Sarkar D;Upadhyay N;Roy S;Rana S C (Mechanical Engineering Dep, National Institute of Technology, Durgapur-713 209, Email: dwaipayan.1106@gmail.com) : Immersed boundary simulation of flow through arterial junctions. Sadhana 2017, 42(4), 533-41.

The present work demonstrates implementation of a mass-conserving sharp-interface immersed boundary for simulation of flows in branched arterial geometries. A simplistic two-dimensional arterial junction is considered to capture the preliminary flow physics in the aortic regions. Numerical solutions are benchmarked against established available experimental PIV results in Ensley et al (Annu. Thorac. Surg. 68(4):1384-1390, 1999) and numerical predictions in Gilmanov and Sotiropoulos (J. Comput. Phys. 207(2):457-492, 2005) and de Zelicourt et al (Comput. Fluids 38(9):1749-1762, 2009). Simulations are further carried out for pulsated flows and effects of blockages near the junctions (due to stenosis or atherosclerosis). Instabilities in the flow structures near the junction and the resulting changes in the downstream pulsation frequency were observed. These changes account for the physiological heart defects that arise from the poorly working valve (due to blockage), giving rise to chest pain and breathing instability, and can potentially be used as a detection tool for arterial diseases.

14 illus, 16 ref

018151   Sankhe S;Sawant A S (NO, , ) : Automatic street lamp. J Commun Engng Syst 2017, 7(1), 25-8.

In modern era, conservation of energy is very important. It is even vital to reduce human efforts by making systems automatic and it also reduces cost of human labour. Automatic street lamp consists of main components like relay, transformer etc. Conservation of nonrenewable energy (electricity) is need of hour and this motive is being achieved by this projects. Street Light Control System which - 309 - operates automatically is not only easiest but also the intelligent system. This system can be set to operate in automatic mode, which regulates the streetlight according to brightness and dimness.

018150   Sanand T V;Pradeep Kumar P;Nair P U;George P P (Liquid Propulsion System Centre, Indian Space Research Organisation, Valiamala, Thiruvananthapuram-695 547, Email: sanandtv@gmail.com) : Numerical and experimental evaluation of performance of centrifugal seals. Sadhana 2017, 42(4), 479-88.

'Centrifugal seals' or 'Slinger seals' offer an attractive choice as non-contact-type sealing in fluid machinery. These seals utilize the radial pressure gradient caused by centrifugal forces in a rotating fluid ring, to create a sealing of the working fluid. Basic construction of a typical seal consists of a rotating disc inside a stationary casing; one side of the disc (sealing side) is provided with a set of slots (Type-1) or vanes (Type-2) to enhance the tangential velocity of the fluid. The other side of the disk (back side) in both the configurations is exposed to high pressure liquid being sealed. Both numerical and experimental investigations of the performance of Type-1 seal (with slots) have been carried out so as to optimize the seal configuration to achieve maximum sealing capacity, with minimum power consumption. A comparison of the performance of Type-1 seal has been made with that of conventional one (Type-2) in view of economy of construction and better sealing with minimal expense of power consumption. A test rig that allows for varying the major geometrical and operating parameters was designed and tests were conducted with water as the medium. Influence of major geometric parameters like dimensions and number of slots, axial/radial clearances and major operating parameters like rotational speed, inlet pressure and sealing fluid bypass flow rate has been investigated. Apart from various pressure, temperature, flow and torque measurements, the interface between the sealing and working fluid for the experiments was captured and recorded using a high speed camera at <126>26,000 frames per second. Geometrical configuration for the slots that maximizes the sealing capacity is arrived through 3D numerical simulations using commercial CFD solver ANSYS Fluent^®. A good agreement is obtained with respect to experimental results. In view of economy of construction and better sealing with minimal expense of operating power, a modified version of Type-1 seal termed as Type-3 seal is investigated. A simple 1D model for prediction of the interface radius during the seal operation, which could be used as a quick design guide, is also presented.

24 illus, 2 tables, 15 ref

018149   Sahu K C (Chemical Engineering Dep, Indian Institute of Technology, Hyderabad, Sangareddy-502 285, Email: ksahu@iith.ac.in) : Review on rising bubble dynamics in viscosity-stratified fluids. Sadhana 2017, 42(4), 575-83.

Systems with a bubble rising in a fluid, which has a variation of viscosity in space and time can be found in various natural phenomena and industrial applications, including food processing, oil extraction, waste processing and biochemical reactors, to name a few. A review of the aspects studied in the literature on this phenomenon, the gaps that exist and the direction for further numerical and experimental studies to address these gaps is presented.

8 illus, 73 ref

018148   Ray A K;Goswami B (NO, CSIR-National Metallurgical Lab, Jamshedpur, Email: asokroy@nmlindia.org) : Stiffness in materials engineering. J Metall Mater Sci 2017, 59(2), 75-83.

Stiffness is shape retention capacity for stable deflection, absorption of energy and failure instabilities. Stiffness is defined by second moment of area and Young's modulus. Second moment of area is design aspect and Young's modulus is material property. Designs may be design of cross sections, bonding, solid or hollow sections and radius of gyrations. Stiffness in strut and panels are facts of density in weight and offsets from density or anisotropy. Stiffness has main effects over mega structures as crash barrier to absorb kinetic energy.

018147   Ravichandran S;Deepu P;Govindarajan R (NO, TIFR Centre for Interdisciplinary Sciences, Hyderabad-500 075, Email: ravis@tifrh.res.in) : Clustering of heavy particles in vortical flows: A selective review. Sadhana 2017, 42(4), 597-605.

Heavy particles in a turbulent flow tend to leave regions of high vorticity and cluster into regions of high strain. The consequences of such clustering have been studied in a variety of situations over the past few decades, and this problem has seen several review papers already. Our objectives in this paper are three-fold. (i) We introduce the reader to the basic ideas, and explain why the problem is interesting. (ii) Using an N-vortex system we present an interesting case where particles are attracted to the vicinity of vortices. A new scaling for the critical Stokes number of attraction is obtained. (iii) We review a number of papers, which are related to cloud physics in this context.

^iia3 illus, 58 ref

018146   Ranjan R;Das T K;Munda B N S;Mandal E;Mandal S K (Electronics and Communication Engineering Dep, National Institute of Technology, Jamshedpur-831 014, Email: ranjan92ravi@gmail.com ) : Development of sensor based on GMI effect for structural health monitoring of engineering component. J Metall Mater Sci 2017, 59(1), 23-7.

The present investigation deals with the development of magnetic sensor based on giant magnetoimpedance (GMI) effect using soft magnetic Co₇₀Fe₂Si₁₃B₁₅ amorphous wire as sensing core element. The GMI property of the - 307 - sensing element has been utilized for development of the sensor which is sensitive to the minute variation of the local magnetic field. An embedded system comprising of hardware and software have been designed and developed to monitor and record the output signal of the sensor. The sensor output is calibrated against the external applied magnetic field. The sensor demonstrates its excellent linearity, repeatability and reproducibility. The GMI sensor is very much useful for detection of the localized magnetic field of service exposed engineering components exposed to an external magnetic field and more specifically, this GMI sensor can be efficiently used for efficient monitoring of structural integrity of engineering components. The conventional non-destructive techniques such as ultrasonic, eddy current, magnetic particle inspection are also used to assess the defects or cracks of engineering components. However, all those methods are unsuitable for monitoring structural degradation as most of the structural components used in industries are of ferromagnetic steel and also the microstructural properties of the components due to their long service period, influence the magnetic and mechanical properties as well. Therefore, the GMI sensor may be more useful to detect the changes of local magnetic field of the aging structure owing to the microstructure changes of the component and thereby, monitor the structural health of the engineering components.

018145   Priya V;Sampath Kumar M C;Balasubramanya N (Civil Engineering Dep, Adhiyamaan College of Engineering, Hosur-635 109, Email: vaishudurga@yahoo.com) : Reduction of electrical conductivity in coir pith and analysis of coir pith leachate obtained-using organic, chemical and biological treatment. Pollut Res 2017, 36(1), 111-5.

In this study, efforts have been made to reduce the Electrical conductivity in fresh coir pith using treatments such as chemical, organic and biological and to check the reduction of leachate parameters before and after treatment. Urea, Rock phosphate and Clostridium perfringens were used for treatment in this analysis for a period of 71 days. It is observed that the biological treatment has been very effective against the removal of EC followed by the organic treatment and chemical treatment. The leachate obtained from biological treatment showed high tendency to reduce the EC and TDS. Also the reduced values of the nutrients proved good the growth of the bacteria.

6 illus, 2 tables, 9 ref

018144   Patel K S;Shukla R K (Mechanical Engineering Dep, Indian Institute of Science, Bangalore-560 012, Email: ratnesh@mecheng.iisc.ernet.in) : Numerical simulation of breakup and detachment of an axially stretching newtonian liquid bridge with a moving contact ine phase field method. Sadhana 2017, 42(4), 467-77.

The extensional, breakup and detachment dynamics of an axially stretching Newtonian liquid bridge are investigated numerically with a dynamic domain multiphase incompressible flow solver. The multiphase flow solver employs a Cahn-Hilliard phase field model to describe the evolution of the diffuse interface separating the liquid bridge fluid from the surrounding medium. The governing axisymmetric Navier-Stokes and Cahn-Hilliard phase field equations are discretized on a continuously expanding domain, the boundaries of which coincide with the planar solid surfaces containing the liquid bridge. The entire formulation, including the fast pressure correction for high density ratios and the semi-implicit discretization that overcomes the numerical stiffness of the fourth-order spatial operators, is performed on a fixed simplified computational domain using time-dependent transformation. Simulations reveal that the dynamic domain interface capturing technique effectively captures the deformation dynamics of the stretching liquid bridge, including the capillary wave formation, necking and interface evolution post breakup and detachment. It is found that the liquid bridge detachment is strongly influenced by the contact angle prescribed at the stationary and moving solid surfaces. At relatively small pulling speeds, the entire liquid is found to preferentially adhere to the less hydrophobic surface. When the prescribed contact angles are equal, however, the liquid bridge undergoes complete detachment so that no liquid resides either on the stationary or on the moving solid surface.

9 illus, 37 ref

018143   Pai S A;Tiwari S;Sundararajan T (Mechanical Engineering Dep, Indian Institute fo Technology Madras, Chennai-600 036, Email: sudaananth@gmail.com) : Effect of external pulsation on kinematics of fluid particles in the field of lamb-oseen vortex pair. Sadhana 2017, 42(4), 489-504.

The effect of external pulsation on a pair of stationary Lamb-Oseen vortices of equal strength has been analyzed to investigate kinematic behavior of a fluid particle. The assumption of vortices being treated stationary or fixed vortex filaments is valid in a reference frame attached to the vortex system with axes along and perpendicular to the line of their centers. Also, it is assumed that change in core shape and size is much small, with least possibility of core merger. In such situations, periodic particle paths are observed and superposition of pulsation becomes beneficial. In the present work, motion of a representative fluid particle is modeled as a non-linear dynamical system by varying both amplitude and frequency of external pulsation. Effect of external pulsation has been brought out with the help of quantification of deviation from periodic paths by using the concept of total average deviation. Results are presented in terms of particle paths, velocity phase plots, velocity signals and their spectra for varying amplitude and frequency of external pulsation.

19 illus, 3 tables, 23 ref

018142   Namshad T;Shrivastava M;Agrawal A;Sharma A (Mechanical Engineering Dep, Indian Institute of Technology Bombay, Mumbai-400 076, Email: atulsharma@iitb.ac.in) : Effect of wavelength of fish-like undulation of a hydrofoil in a free-stream flow. Sadhana 2017, 42(4), 585-95.

Fish-like undulating body was proposed as an efficient propulsion system, and various mechanisms of thrust generation in this type of propulsion are found in the literature-separately for undulating and pitching fishes/foil. The present work proposes a unified study for undulating and pitching foil, by varying wavelength λ (from 0.8 to 8.0) of a wave travelling backwards over the NACA0012 hydrofoil in a free-stream flow; the larger wavelength is shown to lead to the transition from the undulating motion to pitching motion. The effect of wavelength of undulation is studied numerically at a Reynolds number Re=4000, maximum amplitude of undulation A_max=0.1 and non-dimensional frequency of undulation St=0.4, using level-set immersed-boundary-method based in-house 2D code. The Navier-Stokes equation governing the fluid flow is solved using a fully implicit finite-volume method, while level-set equation governing the movement of the hydrofoil is solved using an explicit finite-difference method. It is presented here that the thrust generation mechanism for the low wavelength case undulating (λ=0.8) foil is different from the mechanism for the high wavelength pitching foil. With increasing wavelength, mean thrust coefficient of the undulating foil increases and asymptotes to value for the pure pitching foil. Furthermore, the ratio of maximum thrust coefficient to maximum lateral force coefficient is found to be larger for the smaller wavelength undulating foil as compared with the larger wavelength pitching foil.

11 illus, 25 ref

018141   Nair P;Tomar G (Mechanical Engineering Dep, Indian Institute of Science, Bangalore-560 012, Email: prapanch.nair@gmail.com) : Energy transfer during water entry of solids using incompressible SPH simulations. Sadhana 2017, 42(4), 517-31.

Cavity formation during water entry of a solid corresponds to the deceleration experienced by the solid. Several experimental studies in the past have facilitated qualitative understanding of the relation between flow and impact properties and the type of cavity formed. The types of cavities formed are classified primarily based on the nature of the seal, such as (a) surface seal, (b) deep seal, (c) shallow seal and (d) quasi-static seal. The flow mechanism behind these features and their effects on the speed of the impacting solid require further quantitative understanding. A study of such phenomenon is difficult using the existing CFD techniques owing to the fact that the high density ratios between the two phases, namely water and air, bring in issues with respect to the convergence of the linear system used to solve for the pressure field for a divergence-free velocity field. Based on a free surface modeling method, we present Incompressible Smoothed Particle Hydrodynamics (ISPH) simulations of water entry of two-dimensional solids of different shapes, densities and initial angular momenta. From the velocity field of the fluid and shape of the cavity, we relate the transfer of kinetic energy from the solid to the fluid through different phases of the cavity formation. Finally, we present a three-dimensional simulation of water entry to assert the utility of the method for analysis of real life water - 305 - entry scenarios.

20 illus, 41 ref

018140   Mukherjee S (Earth Sciences Dep, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, Email: soumyajitm@gmail.com) : Shear heating by translational brittle reverse faulting along a single, sharp and straight fault plane. J Earth Syst Sci 2017, 126(1), 1-5.

Shear heating by reverse faulting on a sharp straight fault plane is modelled. Increase in temperature (T_i) of faulted hangingwall and footwall blocks by frictional/shear heating for planar rough reverse faults is proportional to the coefficient of friction (μ), density and thickness of the hangingwall block (ρ). T_i increases as movement progresses with time. Thermal conductivity (K_i ) and thermal diffusivity (k'_i) of faulted blocks govern T_i but they do not bear simple relation. T_i is significant only near the fault plane. If the lithology is dry and faulting brings adjacent hangingwall and footwall blocks of the same lithology in contact, those blocks undergo the same rate of increase in shear heating per unit area per unit time.

1 illus, 46 ref

018139   Mohamed S R (NO, , ) : Forecasting of factors affecting thermiston work productivity estimation by using artificial neural network. J Constr Engng Technol Mgmt 2017, 7(1), 10-21.

The research aims to find factors affecting of Thermiston work productivity and the derivation of an equation to predict the rates of Thermiston work productivity by using artificial neural network technology and compared with traditional methods. The Artificial Neural Network with multilayer by back-propagation error technique for modeling the productivity - 304 - estimation is used, it is founded that the ANN are able to manage to, can predict the productivity for Thermiston work with a good level of. amount of accuracy where the average accuracy (92.5)% and value of (R) equals to (89.5). Also shown that the more influential factor on the Thermiston work productivity by using technology artificial neural networks technique is the level of work, performance and experience, either according to MLR technique the factors level of work, and the security is the most influential factors, and materials are available depending on the questionnaire was the most influential factor on the Thermiston work productivity. From this study was to draw many conclusions and recommendations for future studies.

018138   MNRE (NO, , Ministry of New and Renewable Energy Block - 14, CGO Complex, Lodhi Road, New Delhi-110 003) : Indian geothermal energy development framework. Indian J Pwr River Valley Dev 2016, 66(5-6), 80-6.

The energy scenario in India is fast changing with the emphasis given in the XIth Five Year Plan on non-conventional and renewable sources of energy. Though the dominance of fossil fuels, viz. coal and oil will continue in the energy sector for the next few decades, the concern for reducing the greenhouse gas emissions warrants increasing use of green energy/non-conventional energy sources as a substitute to oil and coal. Solar energy and wind energy are major contributors of the renewable energy as these resources are widely distributed all over India and are available round the year. Geothermal energy is also an additional source of renewable energy with site specific availability and potential for consistent supply in all the seasons/throughout the year.

1 table

018137   Mishra A;Nagesh Kumar G V;Rao B V;Chowdary D D (Electrical and Electronics Engineering Dep, GITAM Univ, Visakhapatnam, Email: drgvnk@rediffmail.com) : Optimal placement and tuning of interline power flow controller for generator contingency management using differential evolution. Indian J Pwr River Valley Dev 2016, 66(1-2), 1-7.

In the competitive electric market of recent times, continuous supply of electricity in normal and contingency condition is mandatory. Hence, post-contingency management of the transmission system is a task to be done most accurately. Generator contingencies have been taken into consideration in this study. In this paper, placement of interline power flow converter (IPFC) using composite severity index (CSl) has been proposed in order to overcome the post-contingency severity condition of the system. The CSl is a combination of line utilization factor (LUF) and voltage stability index (L_mn) in order to predict the severity of the lines accurately. The IPFC has been further tuned using differential evolution for a multi-objective function. The multi-objective function consists of active power loss, voltage deviation, security margin and capacity of installed IPFC. The proposed strategy has been implemented on an IEEE 30 and 57 bus system for verification and illustration purposes.

9 illus, 6 table, 14 ref

018136   Mehta C N;Shukla D D (NO, Rai Univ, Ahmedabad) : Stress life analysis of induction furnace wall for magnesia ramming mass. J Metall Mater Sci 2017, 59(2), 85-101.

Furnaces are most commonly used for melting of materials. Induction furnaces are more beneficial as no fuel is required. It is a problem to find life cycle of Induction Melting Furnace Wall under load variation. The induction melting furnace wall is made of magnesia ramming mass which is one kind of refractory material. The failure occurs due to cyclic thermal stresses due to heating and - 303 - cooling cycles. Temperature distribution and thermal stress distribution fields of the induction melting furnace refractory wall were calculated by using explicit finite difference analysis based on the physical description of its failure under low cycle thermal fatigue conditions. The life span of the refractory wall is required to be found out by means of critical thermal stresses created inside the refractory wall of induction melting furnace wall from modified S-log N Curve.

018135   Maurya S;Shrivastava S (NO, , ) : Layout design, fabrication and characterization of N-channel mosfet. J VLSI Des Tool Technol 2016, 6(2), 13-18.

Primary force behind evolution of semiconductor industry is MOSFET, after its first IC based experimental demonstration in 1960s. It is fundamental working unit of most of the electronic circuits like cells in living being. Number of devices on a single chip has been increased with rapid phase with evolution of new technology of materials. Today there are more than 4 billion transistors are there on a single chip with effective channel length of 45 nm and beyond. A lot complexity has been involved in device fabrication. This paper deals with detailed design of layout, fabrication and. characterization of n-channel metal gate MOSFET fabricated on <100>, p-type silicon substrate using standard process steps and minimum mask levels.

018134   Maurya S;Shrivastava S (NO, , ) : Challenges beyond 100 NM MOS devices. J VLSI Des Tool Technol 2016, 6(2), 1-4.

MOS devices have been aggressively sealed down in research and in production in last few years. Sub-100 nm feature size MOS circuits have been used for many. However, many serious mitations and problems emerged with such a small geometry MOSFETs are used to realize very large-scale integrated circuits. Commercial 45 nm technology node, has much higher production cost and it is one of the greatest concern for scaling down devices beyond 10 nm. This paper deals with challenges and limits of beyond 100 nm technology. Possible limiting factors for the scaling of devices have also been elaborated.

018133   Latif F;Kordorwu V;Nyako K O;Tetteh J T; Anthony Q C (NO, , ) : Effects of fracture properties on oil recovery in tight reserviours. J Petrol Engng Technol 2016, 6(3), 12-31.

Unconventional men-airs, characterized by low permeability are gradually becoming a force to reckon with in today's world owing to the rapid depletion of conventional resources. However, low oil production from tight reservoirs can he. mitigated by implementing hydraulic fracturing. In this study. Schlunberger's eclipse-100 simulator was used to simulate various scenarios in order to determine the. best fracture geometry and the effects of fracture - 302 - properties on oil recovery. The properties considered were fracture half-length, width and number. Oil recovery from the tight reservoir was found to be 0.47% O1P and the application of hydraulic fracturing increased the recovery to 4.78%. O1P sensitivity analysis was carried out by varying well trajectory, porosity, permeability and wettability. It was found out that, fracture geometry of 300 ft half-length. I inch width and a fracture number of 15 is ideal for this reservoir, both technically and economically. An increase in the fracture number affected the spacing greatly. As the number increased, initial production from the reservoir increased. However, cumulative production declined with continued increase in fracture number as spacing decreased. The fracture half-length had a more significant impact on the early time behavior as a result of the fractures reaching further into the reservoir. Increase in fracture width impacted on the late time production behavior of the well by maintaining production for a longer duration. Variations in the reservoir properties after obtaining the. optimum case show that hydraulic fracturing is applicable to tight reservoirs.

018132   Krishnan D S;Thanikonda A K (NO, , Thanikonda, Email: deepak.krishnan@wri.org) : Assessing the impact of Karnataka Electricity Regulatory Commission's open access order for solar power generators in Karnataka. Indian J Pwr River Valley Dev 2016, 66(3-4), 31-42.

On 18 August 2014, the Karnataka Electricity Regulatory Commission (KERC) passed order number S/03/01 called 'Wheeling Charges, Banking Charges & Cross Subsidy Surcharge for Solar Power Generators', whereby all solar power generators in the state who achieved Commercial Operation Date (COD) before 31 March 2018 were exempted from payment of wheeling and banking charges and cross subsidy surcharge for a period of ten years from the date of commissioning. This landmark order provided long term clarity for solar project developers and consumers. For certain categories of consumers (commercial), the exemption meant that solar energy became more viable while planning their energy mix. From KERC's perspective, the main drivers for passing this order was the low rate of growth of solar energy installations in Karnataka and the prevalent trend of a reducing solar tariff seen against rising utility tariffs. The Commission hoped that this measure would facilitate greater and rapid growth of solar energy through third party open access and captive routes. Given the importance of this order, WRl is keen to track its on-ground impact to serve as a feedback mechanism to KERC and as a learning for other state regulators who may be looking for solutions to increase the quantum of solar energy in their states.

3 illus, 3 tables, 24 ref

018131   Kaushik H;Prasad N;Medhi N;Rajkhowa A;Medhi T;Baruah A;Teron T (NO, , ) : Study on oil and gas processing facility in a part of upper Assam basin. J Petrol Engng Technol 2016, 6(3), 1-6.

Crude oil that is produced from the oilfields cannot be directly sent to the refineries for further processing. It must undergo additional processing before being sent to refineries to prevent pipeline corrosion, resolve transportation issues and satisfy the crude specification of the refinery which can be achieved by oil and gas processing facility. It it an integral part of the upstream petroleum industry which meets the required specifications of oil and gas before sent to the refineries. The present work aims to study the typical processes of an oil and processing facility to understand the design, control and optimization of such facility in a part of Upper Assam Basin. The study analyses the existing methods for crude oil and gas processing of the study area and an attempt has been made to develop the existing arrangement of the facility to improve the energy efficiency as well as product quality. The new arrangement of the processing facility can be applied to corresponding oil and gas processing facilities in other parts of the world that hare the similar arrangement as that of the study area.

018130   Joshi Akshay A;Singh P R;Hosmani S S (NO, Kalyani Centre for Technology and Innovation, Bharat Forge Ltd., Pune-411 036, Email: akshay.joshi@bharatforge.com) : Microstructure evolution in boronized inconel 718 superalloy. J Metall Mater Sci 2017, 59(1), 11-21.

This study was focused on the pack-boronizing of Inconel 718 alloy to understand the microstructure evolution at 950 and 1050°. Cross-section of the specimens boronized at 950° showed the formation of silicide top layer and boride layer beneath to it. The separate layer of silicide was not observed for the specimens boronized at 1050°. Ni-, Cr-and Fe-borides were observed in the boride layer. Unlike 950°, borides of various shapes, like the square, pentagonal and hexagonal, were observed in boride layer at 1050°. Boride layer showed very good adhesion to the substrate. Maximum hardness of the boride layer was about 1600-2000 HV, which was about 4-6 times the hardness of the core. On the basis of obtained results, mechanisms of the microstructure development in the boride layer were proposed.

018129   Jajal J A;Patel M L (NO, , ) : Implementation and simulation of high speed dynamic latch comparator for ADC. J VLSI Des Tool Technol 2016, 6(2), 99-103.

As per emerging issues in analog-mixed signal (AMS) design towards high speed and low power, limits the performance of high-speed application., Circuit complexity, speed, offset voltage and resolutions are essential parameter of comparator that affects the Analog-to-Digital Converter (ADC) performance. Based on specifications, to achieve lower offset voltage and higher load drivability of latched comparator is presented. Moreover, the circuit is able to reduce power dissipation as the topology is based on latch circuitry. Resistor-divider structure was used to design a CMOS comparator in TSMC 180 nm technology due to advantage of high speed and no static power consumption. Here, systematic offset voltage is simulated. Achieved parameters are 1.2 GHz sampling rate, above 8 bit resolution, 98 ps propagation delay, 20 mV offset voltage and 77 μW power consumption. In the end, layout was prepared on pyxis (Mentor Graphics) tool.

018128   Jain N;Joshi K K (NO, , ) : Improved performance by using K-means clustering in vehicular AD HOC network. J Commun Engng Syst 2017, 7(1), 17-24.

VANETs are formed by applying the principles of MANETs, in which all node, i.e., vehicles can pursue traffic law with high speed. VANETs support two types of communication: vehicle - to- vehicle (V2V) and vehicle to-infrastructure (V2[). Vehicles communicate to RSU for the exchange of keys for the security purpose and RSU communicate to Authentication Server (AS) for the formation of secret keys. But in existing work they perform nonsymmetric cryptography in which XOR operation is performed at authentication server which increases the size of key. In this paper we proposed a technique in which we form the cluster of vehicles then perform login for sending the data. Our results are shown in NS2 simulation which proves that the performance of network improves in terms of Throughput, Routing Overhead and Packet Delivery Ratio.

018127   Harpreet Kaur;Manoj Kumar;Sharma A K;Singh H P (NO, , ) : Performance analysis of DWT based OFDM system using SRRC filter in mobile wimax over fading environment. J Commun Engng Syst 2017, 7(1), 1-10.

Wavelets amid its capability to provide simultaneous information in both time ami frequency domain, along with minimization of interference and improved bandwidth efficiency, is considered broadly as an efficient approach to replace fast Fourier transform (FFT) in the conventional orthogonal frequency division multiplexing (OFDM) systems. Efficient filter pulses are employed spectrally in such systems in order to mitigate the effect of inter-symbol interference (ISI) as well as satisfy the bandwidth limitations imposed by the multipath fading channels. In this paper, SRRC pulses arc employed as transmit and receive fillers to perform matched filtering in the wavelet based OFDM system of mobile worldwide interoperability for microwave access (Wimax) that facilitate to meet higher data rate demand along with reducing the probability of errors at the receiver. The physical layer performance of this simulated system is measured and compared in terms of bit error rate (BER) by varying noise ratio (SNR) for different modulation techniques under wireless channel with realistic multipath fading and noisy conditions with model specifications in a semi-urban environment. The simulation outcome demonstrates significant improvement in BER which substantiates to enhance the performance of the physical layer in mobile Wimax under realistic environment conditions for various modulationschemes. Performance analysis by varying certain parameters of SRRC filter is also demonstrated to measure its comparative effectiveness. The simulation model is developed in MATLAB.

018126   Gupta V;Gupta A K (NO, , ) : Design and implementation of low power 8-bit level crossing ADC. J VLSI Des Tool Technol 2016, 6(2), 33-43.

Implantable medical devices, electronic gadgets, wireless communication elements and many other such applications require low power electronic circuits. Analog to digital converters are essential part of most of such circuits. This paper presents a design of the level crossing analog to digital converter (LC-ADC) architecture. The proposed circuit and layout has been implemented in semi-conductor laboratory (SCL) 180 nm technology and its performance was evaluated using cadence virtuoso at supply voltage 0.8 V. DRC, LVS and PEX were performed using calibre. The pre- and post-layout simulation results have been compared using Hspice circuit simulator The proposed ADC consumes 90 nW-184nW power in frequency range 0.005-3 KHz and takes up 0.025 mm² silicon area.

018125   Ghosh P K;Yadav A;Das A;Mukherjee S (Electrical Engg Dep, Ideal Institute of Technology, Kalyani-741 235, Email: pritish_ghosh80@rediffmail.com) : Wind turbine- an approach to efficiency improvement. Indian J Pwr River Valley Dev 2016, 66(1-2), 8-13.

The paper deals with the proper and detailed explanation of the principles on design and maximum efficiency of a wind turbine. Wind turbine rotates on the principle of conservation of energy through conversion of wind kinetic energy to mechanical energy that drives the turbine to further produce electricity. The turbine needs to work at it best to maximize the access of wind kinetic energy for which different control mechanisms are provided in the wind turbine. The design needs to be best so as to sustain different weather conditions and to perform at its optimum level. However the wind turbine is not capable to exploit all the - 299 - energy available to it and hence is not 100 per cent efficient. If we can install an additional mechanism by virtue of which for the same input wind power (K.E OF THE WIND) the output power obtained is enhanced by some amount. The additional installed mechanism is of perpetual motion. But still it is one of the major unexploited never ending sources which has a large scope in the future with this field being the major focus of research.

13 illus, 13 ref

018124   Garai A;Pal S;Mondal S;Ghosh S;Sen S; Mukhopadhyay A (Mechanical Engineering Dep, Jadavpur Univ, Kolkata-700 032, Email: amlangarai@gmail.com) : Experimental investigation of spray characteristics of kerosene and ethanol-blended kerosene using a gas turbine hybrid atomizer. Sadhana 2017, 42(4), 543-55.

Gas turbines have wide application as prime movers in transportation and power generating sectors, most of which are driven by fossil fuels like kerosene. The conventional fuels are associated with problems of air pollution, and the fuel reserves are getting depleted gradually. Addition of ethanol in kerosene leads to better spraying characteristics. The present work deals with the spray characteristics of pure kerosene and 10%-ethanol-blended (by volume) kerosene using a novel gas-turbine hybrid atomizer. Here the inner air and outer air enter in the same and opposite directions, respectively, with respect to the fuel flow direction into the atomizer and a high swirling effect occurs outside the nozzle. The fuel stream is sandwiched between two annular air streams and the flow rate of inner and outer air is varied continuously. Various spray stages like distorted pencil, onion, tulip and fully developed spray regimes have been observed. The breakup length, cone angle and sheet width of the fuel stream are analysed directly from backlit imaging for different fuel and air flow rates. From the image processing, it is observed that breakup occurs at an early stage for 10%-ethanol-blended kerosene due to low viscosity of ethanol. It is also observed that at higher air flow rate, breakup occurs at an early stage due to turbulent nature of the fuel stream.

16 illus, 37 ref