Dr. Mysuru Siddalingappa Bhagyashekar, Professor, Administrator, Mentor, and Guide obtained his B.E in Mechanical Engineering from Bangalore University(1988), PG Diploma in Industrial Pollution Management from National Institute of Environment, Lucknow (1992) M.Sc. Engg (by Research) in mechanical engineering with research on composite materials from SJCE, Mysore, Mysore University (1997) and Ph.D. in Mechanical Engineering with research on polymer composites at NAL from Bangalore University (2007).
Dr. MSB has a total of 30 years of rich experience in Academics, Research and Administration and is associated with “Research Centers” at DBIT and RRIT and working on Development and characterization of polymer composites and materials for energy systems. He has published more than 58 research publications in refereed journals and conferences and edited 8 conference proceedings. He is a Professional Member of Indian Society of Theoretical and Applied Mechanics, Indian Society for Advancement of Materials and Processing Engineers, Indian Institute of Production Engineers, Indian Society for Technical Education and IAENG and is Editorial Board Member of International Journal of Advanced Mechanical Engineering and guest reviewer of journal of Minerals and Materials Characterization and Engineering.
Experimental testing of scroll machine driven by compressed air for power generation and its integration in small scale organic Rankine cycle Pavan Kumar REDDY, M S BHAGYASHEKAR Journal of Thermal Engineering, 2021 Organic Rankine Cycle (ORC) is a proven technology in the field of waste heat recovery and present days ORC is extensively being used in exploiting biomass, geothermal and solar energy. The overall performance of ORC depends on the expander, making it a core component of the system. Generally, these expanders are classified into velocity type and displacement type. The velocity type expanders find their applications in large scale power generation and are not preferred in small scale power applications as their rotational speeds exponentially increase with a decrease in expander power output. As a result, the displacement type expanders are best suited for small scale power generation in ORC. Yet, till date expanders capable of producing power at small scale are not commercially available in the market for ORC application. As an effect commercially available scroll compressors are modified to work as expanders in ORC systems. The present study aims to examine the feasibility of using one such scroll compressor as an expander in ORC with and without modification. A test rig was developed to test the compressor running in reverse as expander using compressed air, before and after modifications. The scroll machine was tested for operating conditions consisting of pressure varying from 0.5 bar to 4.5 bar and the load varying from 0.2 kg to 2.2 kg for a constant airflow rate. The configurations tested were, scroll compressor with the suction port as inlet, modified scroll compressor with the suction port as inlet and modified scroll compressor with discharge port as an inlet. Based on the experimental test data obtained it is observed that, in all three configurations, for various loading conditions at given inlet air pressure there exists a maximum power generation point and a further increase in the load at given pressure has a negative effect on power output. Also, a significant increase in speed is observed from 300 to 4250 rpm at no load condition with increasing inlet air pressures. Maximum power of 210 W was achieved at a load of 1.1 kg with the inlet pressure of 4.5 bar for modified scroll machine when the discharge port was used as an inlet. Finally, it is recommended to use a modified scroll machine with discharge port as inlet as it gives more power when compared with other configurations for the same operating conditions.
Influence of Edge Condition of Cutting Tool on Cutting Force and Surface Roughness while Machining Aluminum-Fly Ash Composites C.R. Prakash Rao, M.S. Bhagyashekar, M.S. Rajagopal, M. VedaVyasa Materials Today Proceedings, 2018 Metal Matrix Composites (MMCs) are adopted to fabricate machine parts and automobile parts owing to its properties, however the MMCs are required to be machined to obtain final component. While turning these MMCs, the cutting tools fail due to notch wear followed by built up edge and macro chipping which leads to increase of cutting force and surface roughness. Hence present research paper is aimed at study of the cutting force and surface roughness while turning Al6061 Fly ash composite using CGGN120304 style, edge rounded carbide inserts. The cutting speed selected was between 150m/min to 650m/min in steps of 125m/min, feed of 0.15 mm/revolution, 0.2 mm/revolution, 0.25 mm/revolution and constant radial depth of cut of 1.0 mm. Experimentation were carried out following ISO3685 standards. The experimental results revealed that while turning composites, Surface roughness, Cutting force and burr folding were found lower when K10 grade carbide insert used with lower edge rounding. Cutting edges was found intact with 80 micron and 100 micron edge rounding at all machining parameters.
Effect of machining parameters on surface roughness while turning metal matrix composites-an experimental approach C.R. Prakash Rao, M.S. Bhagyashekar, P. Chandra, D.V. Ravikumar Materials Today Proceedings, 2018 Metal Matrix Composites (MMC’s) reinforced with silicon carbide are preferred for automobile, aviation and marine application owing to its strength to weight ratio however these parts requires turning operation. The turning operation is intended to convert raw materials in to the final output having the desired quality in terms of component dimension and surface roughness. The desired quality of the components can be obtained by proper selection of parameters during turning MMCs. Hence present research paper is aimed at the study of the surface roughness while turning MMC’s using CGGN120304 style, K10 grade uncoated tungsten carbide inserts. The cutting speed selected was 300m/min, 450m/min and 600m/min, feed of 0.08 mm/revolution, 0.16 mm/revolution, 0.24 mm/revolution and constant radial depth of cut of 1.5 mm. Experiments were conducted following ISO3685 standards. The Surface roughness was measured using SJ201P surface roughness measuring equipment. The experimental results revealed that while turning composites, Surface roughness were found lower when 600 m/min and 0.08 mm/revolution were used for machining. The cutting edges were subjected to high BUE at 0.08 mm/rev at all cutting speeds.
Effect of mono Al / Cu and hybrid (Al-Cu) particulates on Thermal conductivity of epoxy composites K. Srinivas, M.S. Bhagyashekar Materials Today Proceedings, 2017 The present study reports the enhancement of thermal conductivity of epoxy and its composites containing metallic micro particulates of Al, Cu and hybrid (Al-Cu) particulates. The filler fractions were varied from 10% to 40% by weight for all the three composites systems. Investigations showed that increased particulate content enhances the thermal conductivity of epoxy. Further, epoxy composites having hybrid (Al-Cu) fillers exhibits higher thermal conductivities than epoxy composites filled with mono fillers Al/Cu alone. Analytical models to predict thermal conductivity such as Maxwell, Hashin, Nielsen, and series were used to compare thermal conductivity found by experiment. Thermal conductivity predicted by some of the analytical models is in agreement with thermal conductivity determined by experiment.
Optimization study of ammonia and glutaraldehyde contents on vulcanization of natural rubber latex Anish Johns, M. P. Sham Aan, Jobish Johns, M. S. Bhagyashekar, Charoen Nakason, Ekwipoo Kalkornsurapranee Iranian Polymer Journal English Edition, 2015 This manuscript presents a continuation work on a simple system to vulcanize natural rubber using glutaraldehyde as a cross-linking agent. Natural rubber latex consists of protein which is allergenic to human body. The protein immobilization behavior of glutaraldehyde is of greatest interest to conduct this study. A study to determine the optimum condition for the vulcanization of the newly introduced system was carried out using glutaraldehyde as a cross-linking agent. Efforts were made to find out the best combination of glutaraldehyde and ammonia to vulcanize natural rubber latex with superior physical properties. Direct vulcanization method was employed to prepare natural rubber vulcanizates from natural rubber latex. The mechanical performance of the vulcanized natural rubber was determined for various combinations of ammonia and glutaraldehyde. Superior tensile properties were observed for the vulcanized rubber prepared from a very high ammonia natural rubber latex. The activation energy of the degradation of the vulcanizates was determined from thermogravimetric analysis. The cross-link density of the vulcanized rubber was determined from swelling experiments in toluene. The very high ammonia natural rubber latex (0.9 wt% ammonia) with 15 mL of 10 wt% glutaraldehyde solution was found to be the effective combination to vulcanize natural rubber latex with excellent properties. Advantage of this technique is the possibility of directly vulcanizing natural rubber latex at low temperature.
Wear behaviour of epoxy hybrid particulate composites K. Srinivas, M.S. Bhagyashekar Procedia Engineering, 2014 This paper presents the tribological behaviour of epoxy composites containing three different particulate fillers. The RT cured epoxy composites subjected to post cure cycle containing particulate Gr, SiC and Gr-SiC of length 25 mm and diameter 10 mm were the pin specimens and EN31 steel was the disc of the computerized pin on disc wear tester. The results show that the synergic effect of hybrid filler Gr-SiC is to improve the wear resistance when compared with that of Gr/SiC. The improvement in wear resistance for the composite containing 5%SiC 35%Graphite is 85% when compared with epoxy, 25% over composite containing 40%Gr and 36% over 40%SiC. The composites containing 5% Gr and 35% SiC exhibits highest wear resistance.
Preliminary studies on mecahnical and metallurgical behaviour of friction stir welded butt joints B.N. Venkatesha, M.S. Bhagyashekar Procedia Engineering, 2014 The AA6061 and AA6063 metal plates are Friction stir welded to obtain butt joints, Microstructure, Microhardness and tensile strength in the weld examined. The Microstructure evaluation of AA6061 shows that the Fusion with parent metal is good, Grains are slightly elongated at the heat affected zone and Microstructure evaluation of AA6063 shows that grains are severely elongated at HAZ. Vickers Microhardness evaluation of AA6061 shows that after Friction Stir welding (FSW) at parent metal Vickers Microhardness slightly higher than weld zone. Vickers Microhardness is high at HAZ for AA6061. Vickers Microhardness of AA 6063 at the weld region is higher than HAZ, Parent metal. Vickers Microhardness of AA6063 is higher than AA6061 before and after Friction Stir welding. Ultimate tensile strength of AA6061 is greater than AA6063 both before and after FSW.
Effect of machining parameters on the surface roughness while turning particulate composites C.R. Prakash Rao, M.S. Bhagyashekar, Narendraviswanath Procedia Engineering, 2014 Metal matrix composites being used in automobile, aviation, naval, space and other structural applications because of their unique balance of physical and mechanical properties. The metal matrix composites are produced using diverse technologies in order to meet the market demand such as lower density, higher wear resistance, thermal stability at lower cost per component. Composite materials replace almost all the monolithic material while posing challenges for machining hence are graded as difficult to machine materials. The hetrogeneous structure of the composite materials leads to the failure of cutting tool during machining composites are mainly attributed for the presence of hard particles which leads to higher surface roughness value. Thus, present paper presents the results on surface roughness values of K10 grade carbide and Poly Crystaline Diamond (PCD) inserts while turning Al6061-flyash composites containing 0% to 15% fly ash in step of 5%. Parametric studies have been carried out as per ISO3685 standards following dry machining condition. The machining parameters are cutting speeds of 300m/min to 600m/min in step of 100m/min, feed of 0.06 mm/revolution to 0.24 mm/revolution in step of 0.06 mm/revolution using a constant depth of cut of 1.2 mm which is equal to three times to the nose radius of the cutting tool. The results revealed that PCD inserts exhibits lower surface roughness while turning composites containing 10% filler material when compared with that of K10 grade tungsten carbide insert.
