The engine, which uses both conventional diesel fuel and LPG fuel, is referred to as ‘LPG–diesel dual fuel engines’. LPG dual fuel engines are modified diesel engines which use primary fuel as LPG and secondary fuel as diesel. LPG dual fuel engines have a good thermal efficiency at high output but the performance is less during part load conditions due to the poor utilization of charges. This problem can be overcome by varying factors such as pilot fuel quantity, injection timing, composition of the gaseous fuel and intake charge conditions, for improving the performance, combustion and emissions of dual fuel engines. This article reviews about the research work done by the researchers in order to improve the performance, combustion and emission parameters of a LPG–diesel dual fuel engines. From the studies it is shown that the use of LPG in diesel engine is one of the capable methods to reduce the PM and NOx emissions but at same time at part load condition there is a drop in efficiency and power output with respect to diesel operation

Lithium-ion batteries (LiBs) are seen as a viable option to meet the rising demand for energy storage. To meet this requirement, substantial research is being accomplished in battery materials as well as operational safety. LiBs are delicate and may fail if not handled properly. The failure modes and mechanisms for any system can be derived using different methodologies like failure mode effects analysis (FMEA) and failure mode methods effects analysis (FMMEA). FMMEA is used in this paper as it helps to identify the reliability of a system at the component level focusing on the physics causing the observed failures and should thus be superior to the more data-driven FMEA approach. Mitigation strategies in LiBs to overcome the failure modes can be categorized as intrinsic safety, additional protection devices, and fire inhibition and ventilation. Intrinsic safety involves modifications of materials in anode, cathode, and electrolyte. Additives added to the electrolyte enhance the properties assisting in the improvement of solid-electrolyte interphase and stability. Protection devices include vents, circuit breakers, fuses, current interrupt devices, and positive temperature coefficient devices. Battery thermal management is also a protection method to maintain the temperature below the threshold level, it includes air, liquid, and phase change material-based cooling. Fire identification at the preliminary stage and introducing fire suppressive additives is very critical. This review paper provides a brief overview of advancements in battery chemistries, relevant modes, methods, and mechanisms of potential failures, and finally the required mitigation strategies to overcome these failures.

The aim of this review article is to consolidate the important research works dedicated to polymers which are mainly used target material for heat transfer applications. The requirement of present day heat transfer equipment is compactness, lightweight, manufacturability, and lower cost. Materials like copper and aluminum though have better thermal conductivity but they are expensive and also heavy. Polymers are cheaper and easy to manufacture, recycle though they have sufficiently lower thermal conductivity compared to copper and aluminum. Polymer materials are thermally insulating material. It is too difficult to improve the amorphous nature of polymer material in order to achieve high thermal conductivity. One key path to increase the thermal conductivity of a polymer is to reinforce high thermal conductive fillers in the host matrix. In this review paper, an attempt is made to explore and summarize various key paths suggested by the researchers to develop high thermal conductive polymer composites.

A major part of the heat supplied in an IC engine is not realized as work output, but dumped into the atmosphere as waste heat. If this waste heat energy is tapped and converted into usable energy, the overall efficiency of the engine can be improved. The percentage of energy rejected to the environment through exhaust gas which can be potentially recovered is approximately 30-40% of the energy supplied by the fuel depending on engine load. Thermoelectric modules (TEM) which are used as Thermoelectric generators (TEG) are solid state devices that are used to convert thermal energy from a temperature gradient to electrical energy and it works on basic principle of Seebeck effect. This paper demonstrates the potential of thermoelectric generation. A detailed experimental work was carried to study the performance of TEG under various engine operating conditions. A heat exchanger with 18 TEG modules was designed and tested in the engine test rig. Thermoelectric modules were selected according to the temperature difference between exhaust gases side and the engine coolant side. Various designs of the heat exchangers were modeled using CAD and analysis was done using a CFD code which is commercially available to study the flow & heat transfer characteristics. From the simulated results it was found that rectangular shaped heat exchanger met our requirements and also satisfied the space and weight constraint. A rectangular heat exchanger was fabricated and the thermo electric modules were incorporated on the heat exchanger for performance analysis. The study also revealed that energy can be tapped efficiently from the engine exhaust and in near future TEG can reduce the size of the alternator or eliminate them in automobiles

To meet the present requirements of the automotive industry, there is continuous search to improve the performance, exhaust emission, and life of the IC engines. The meet the first two challenges, researchers are working both on newer engine technologies and fuels. Some of the published work indicates that coating on the combustion surface of the engine with ceramic material results in improved performance and reduced emission levels when fueled with alternate fuel blended fuels, and this serves as a base for this work. Normal-Butanol has molecular structure that is adaptable to gasoline, and it is considered as one of the alternative fuels for SI engines. Blending butanol with gasoline changes the properties of the fuel and alters the engine performance and emission characteristics. This is because heat which is released at a rate as a result of combustion of the compressed air–fuel mixture in the combustion chamber gets changed with respect to change fuel properties, air fuel ratio, and engine speed. An experimental investigation is carried out on a partially insulated single cylinder SI engine to study the performance and emission characteristics when fueled with two different blends of butanol and gasoline. The cylinder head surface and valves are coated with a ceramic material consisting of Zirconium dioxide (ZrO2) with 8% by weight of Yttrium Oxide (Y2O3) to a thickness of 0.3mm by plasma spray method. Two different fuel blends containing 10% and 15% by volume of butanol in Gasoline are tested on an engine dynamometer using the uncoated and ceramic coated engines. The results strongly indicate that combination of ceramic coated engine and butanol gasoline blended fuel has potential to improve the engine performance