THIRUSELVAM K

The present study focuses on improving the thermal efficiency of CI engine by decreasing the heat transfer in combustion chamber. In this paper, analyze the different ceramic powder coating materials on the Nickel chromium cast iron alloy cylinder liner by conducting various tests in order to finalize the best ceramic coating on the cylinder liner. Four different coating materials combination have been chosen for the analyses which are Yttrium Stabilized Zirconia (YSZ), Aluminum oxide (Al2O3), Aluminum Oxide and Yttrium Stabilized Zirconia (Al2O3 +YSZ), Aluminum Oxide and Titanium Oxide (Al2O3+TiO2). The optimum level of thickness 100 microns has been chosen for the observing the results. The mechanical strength test of wear test, adhesive test, SEM and EDX test, in additionally flow analyze test of CFD have been conducted. From the results, it's showed that combination of Aluminum Oxide and Titanium Oxide (Al2O3+TiO2) had better ceramic coating than other materials.

Improvement in thermal efficiency and reduction in emission from diesel engines are major thrust research work in all around the world. This research work is on the performance and emission characteristics of diesel engine using Low Heat Rejection (LHR) techniques of thermal barrier coated cylinder liner and piston. A piston was coated as 100 micron thickness and three cylinder liners were coated in the thickness of 100,150 and 200 micron. Piston and cylinder liners were coated with equal percentages of Alumina and Yittria Stabilized Zirconia powder using the plasma spraying coating method. The test results compared with base engine showed reduction in the performance parameter of specific fuel consumption (SFC) on an average by 6.11%, 12.78% and 16.89%, while the brake thermal efficiency increased by 1.68%,3.75% and 5.19% in 100,150 and 200 micron thickness coated cylinder liner used engine respectively. There was reduction in Carbon monoxide (CO), unburned hydrocarbon (HC) and smoke emissions levels while Nitrogen Oxide (NOx) emission was slightly higher in the coated engine compared with the uncoated engine in all load conditions. Overall, 200 microns thickness coated cylinder liner showed a better performance parameter and low emission compared with other cylinder liner coated engine.

The depletion of fossil fuel resources at a faster rate in the present world of economic competitiveness is generating an essential demand for increase in efficiency of internal combustion engines. The use of coating in the automotive industry has been found to yield a significant effect on the efficiency of engines. Higher the operating temperature more will be the efficiency of the system. However, such higher temperatures demand for enhanced temperature resistant materials to be used. This paper presents a review on the various aspect and usage of thermal insulating materials (commonly known as thermal barrier coatings).

The thermal barrier coated combustion chamber parts of cylinder liner, piston head,valve head and cylinder
head in a diesel engine used to reduce the heat flow out to the system thereby would be achieved better performance and emission characteristics in an engine.In this study, yttrium stabilized zirconia (YSZ) and alumina (Al2O3) mixed ceramic powder used as thermal barrier coating material because of required coating properties of low thermal conductivity , high thermal expansion coefficient, good bonding strength and high thermal shock resistance material compared with
other ceramic materials. The suitable thickness of coating was selected by comparing temperature distribution and heat transfer rate using finite element analysis. The coating thickness is considered 0.1mm, 0.15mm and 0.2mm on both cylinder liner and piston head. The results showed the increase of thickness caused to reduce the heat transfer rate and maintained high temperature in the combustion chamber.

Various research works are being undertaken around the world on the subject of thermal efficiency improvisation and emission reduction from diesel engines. This research work analyzes the performance and emission characteristics of a thermal barrier coated diesel engine which used palm biodiesel. The piston and cylinder liners were coated with equal percentages of alumina (Al 2 O 3) and yittria-stabilized zirconia (YSZ) powder using plasma spraying coating method. The piston was coated with 100 μm thickness and the two cylinder liners were coated with 150 and 200 μm thicknesses and were used to analyze the performance and emission characteristics. Test results of the thermal barrier coated engine using palm biodiesel were compared with the results derived from the base engine. The tests revealed an increase of 3.8% specific fuel consumption (SFC) as an average when neat palm biodiesel was used in the base engine. Interestingly, the palm biodiesel used in the 150-and 200-μm thick thermal barrier coated engine was responsible for a significant decrease of the SFC by an average of 4.18% and 8.05% respectively. The brake thermal efficiency was found to decrease on an average of 1.02% when tests were run using the neat palm biodiesel in the base engine. But an average proportionate increase of 0.72% and 2.19% was visible when palm biodiesel was used in the tests conducted on the 150-and 200-μm thick thermal barrier coated engine. There was also an understandable brake specific reduction of 0.991 g/kWh carbon monoxide (CO) emission and 0.025 g/kWh unburned hydrocarbon (HC) levels. The nitrogen oxide (NO x) emission was observed as 14.06 g/kWh in the 200-μm thick thermal barrier coated engine which was slightly higher when the results were compared with that of the uncoated engine. The novelty of this research investigation is based on the usage of yttrium-stabilized zirconia and alumina thermal barrier coating on the cylinder liner and piston head of engine. This is justified due to the fact that most of the previous investigations undertaken focused on the thermal barrier coating in the piston, valve, and cylinder head alone. The utility factor of the palm biodiesel (B 100) in the low heat rejection engine has also proved to be another significant and novel factor in the present investigation outlined in this paper. This is mainly due to the fact that the ongoing investigations in this realm concentrated only on blends of 20 to 30% of palm biodiesel with diesel fuel in the low heat rejection diesel engine.

This work investigates the effect of thermal barrier coating and addition of cerium oxide nanoparticles to the palm biodiesel fuelled diesel engine. The combustion chamber parts of cylinder liner and piston were coated 200 and 100 micron thickness respectively using equal percentages of Yittria Stabilised Zirconia (YSZ) and alumina powder in plasma spraying technique. The 30 ppm and 60 ppm of cerium oxide (IV) nanoparicles were added to the palm biodiesel fuel separately. The performance and pollution parameters were analysed initially using a thermal barrier coated (TBC) engine with neat palm biodiesel. Cerium oxide (IV) nanoparticles were then added to the palm biodiesel and their effects were compared with the base engine. The final performance results showed reduction in the specific fuel consumption on an average of 11.86%, 16.92% and 20.57%, while brake thermal efficiency was increased by 3.21%, 4.28% and 4.82% in neat palm biodiesel fuel, 30 ppm and 60 ppm CeO 2 mixed palm biodiesel fuel used TBC engine respectively. Carbon monoxide and unburned hydrocarbon emission were reduced by 2.2% and 3.7% and nitrogen oxide emission was increased by 1.7% for TBC engine. However, the use of oxygen denoting catalyst of cerium oxide nanoparticles caused a 2.4% reduction in nitrogen oxide emission.