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For upgrading/new engine development, the piston and cylinder head are the most exposed members due to amplified mechanical and thermal loadings. Mechanical loading is basically due to the combustion gas pressure in the combustion chamber and its scale can be judged in terms of peak cylinder pressure. Thermal loading is due to temperature by heat flux acting on the piston surface, cylinder liner and the cylinder head. The importance of the various loads applied on the head and cylinder block in operation was assessed and a method of predicting their influence on the structural integrity of the components described by doing actual test on engine test bench. Therefore, it’s very important to have thermal survey of the engine. The engine thermal survey test was primarily developed to measure the temperature in the head of the engine to determine if the temperatures that are measured are within the design guidelines for appropriate engine operation.

Automotive Air Conditioning is the process of removing the heat and moisture from the interior of an occupied space to improve comfort of occupants. A condenser is a device or unit used to condense refrigerant from its gaseous to its liquid state, by cooling it. In so doing, the latent heat is given up by the substance and transferred to the surrounding environment. It is made of Aluminum Alloy Material and subjected to very high internal stresses due to refrigerant pressure, thermal / inertia and dynamic load. In order to evaluate the structural integrity of the condenser assembly under these loading conditions, operating frequency should be far away from the resonance frequency and component design should be robust to sustain external excitation load coming from the engine & road. The above design evaluation criteria is also applicable for piston of AC’s reciprocating compressor.

The forged connecting rod and pin experience a large amount of stresses due to cyclic load for a long period of time induced by the reciprocating movement of the piston. The proposed work focused to produce lightweight composites with high strength using waste flyash and simple manufacturing process. In this context, the proposed experimental work was formulated to develop aluminium alloy hybrid metal matrix composite of A356 alloy with silicon carbide and flyash processed through stir cum squeeze casting process under optimal parametric condition. The samples were subjected to varying flyash content of 0, 5, 10wt.% and SiC of 5wt.% kept constant. Responses like metallography, hardness, impact strength, flexural strength, fatigue strength were observed for the manufactured hybrid composites. There was a significant improvement in the properties with a higher weight percentage addition of 10wt.% flyash and 5wt.% SiC with A356 hybrid composites.

Vehicles are one of the main sources of pollution in India, which produce substantial amount of pollutants. Gaseous pollutants are reason for major health problems; hence emission legislations are becoming increasingly stringent all over the world. India is also following the global trend of migrating in the Off-highway segment from Trem IIIA to Stage V legislation by 2024. This legislation change is calling for technological upgrade of all existing engines. EGR has been successfully proved as a useful technology to reduce NOx by decreasing the oxygen concentration and the peak temperature of the combustion. Due to compact design and space restriction, the distance required for the homogeneous mixing of fresh air and EGR is not enough. Therefore, the mixing of the EGR and distribution of the EGR over the cylinders may not be equal.

Piston is the most imperative part of an automotive engine in which it exchanges drive due to expanding gas in the cylinder to the crankshaft through the piston rod. During the combustion of fuel charge inside the ignition chamber, high pressure and temperature are developed and the piston is imperiled to high mechanical and thermal stresses. The main objective of the proposed work is to analyse the stress distributions and thermal behaviour of uncoated A356 with 5wt% SiC and 10wt% Fly Ash HMMC piston crown and Plasma sprayed Yttrium Stabilized Zirconia (Y-PSZ) coated A356 with 5wt% SiC and 10wt% Fly Ash HMMC piston crown. A356 with 5wt% SiC and 10wt% Fly Ash HMMC were fabricated via squeeze casting to improve the performance of a petrol engine. A structural model of an HMMC piston crown was made using CREO software and structural and thermal analysis was done using ANSYS. Further coupled field analysis is done to find the stress and temperature distribution on the piston.

Waste cooking oils (WCOs) are renewable and in nature can be directly used as fuel into the compression ignition engines. However, the reduction in brake thermal efficiency and increasing smoke emission and oxides of nitrogen need to be solved. There are more techniques used past researchers to improves the performance and reduced the emissions characteristics of WCO. In this present work, an experimental investigation made on the effect of ethanol on engine's behavior using Waste Cooking oil (WCO) based dual fuel diesel engine. A single-cylinder diesel engine was operated and modified the intake to operate dual fuel mode at the maximum power output of 3.54 kW. Ethanol is introduced as primary fuel into the intake manifold and WCO as pilot fuel. The ethanol energy share (EES) of the total fuel was varied from 5% to 40% with a step of 5%, at fixed engine speed equal to 1500 rpm.

This paper deals with the performance, emission and combustion features of a single cylinder four stroke compression ignition engine with fuel injection timing at advancement and retardment. The current experiment was conducted on a single cylinder four stroke diesel engine fuelled with microalgae methyl ester blended with pure diesel in the proportions of 30% and 70% respectively and it was designated as B30 (30% Microalgae methyl ester + 70% Pure diesel). The present test was carried out at three different fuel injection timings such as 190 R CA (Retarded crank angle), 230 S CA (Standard crank angle) and 270 A CA (Advanced crank angle) BTDC.

In a high-speed DI diesel engine, fuel sprays impinge surely on a wall of a piston cavity. Then the phenomenon of the heat transfer between the impinged spray and the wall appears and it has the strong effect on the combustion processes of the engine. The purpose of this study are to clarify basically the heat transfer characteristics. In the experiments, the fuel was injected into the quiescent inert atmosphere with a high temperature under high pressure field, and an evaporative single diesel spray was impinging upon a flat wall. And, the temperature distribution on the wall surface in a radial direction was detected by the Loex-Constantan thin film thermo-couples. Thus, the heat flux between the impinged spray and the wall surface was calculated from the temperature profile within the wall by Fourier's equation using the finite difference method, under the assumption of the one-dimensional heat conduction.

In this study, a computer program has been developed which predicts the variation of the volumetric efficiency with the change of design of the intake system effectively by the analysis of the flow in each part of a multi-cylinder compression ignition engine. For the calculation of the flow in the intake and exhaust systems, the method of characteristics has been used, and the double Wiebe's function has been adopted for the calculation of the heat release rate in the cylinders. The accuracy of presented method has been proved through the comparison between the simulation and the experimental results over the various engine speeds and intake pipe lengths.

This study describes the results of transient behavior for a six-cylinders four-stroke turbocharged diesel engine during the change in operating conditions of the engine by using the computer simulation with measurements on test bed. In order to obtain the dynamic behaviors of the engine, the transient simulation are conducted with serveral kinds of inertia moment ratio in turbocharger and engine, a rapid large load application to the engine, and changes of governor gain constant. From the results of this study, the following conclusions may be summarized. Turbocharger lag is the main cause of the inferior transient performances of turbochared diesel engines. A reduction in the turbocharger moment ratio of inertia brings about the improvement of acceleration performance of disel engines. An increase of the engine moment ratio of inertia decreases cyclic variations of the engine speed.

The problems causing idle combustion variability are identified. Photographic evidence identifying the various types of ignition kernel growth which influence variability, along with variations in residual gas composition are identified. Combustion variability is quantified in terms of peak cylinder pressure and IMEP variation. The reduction of cyclic variability achievable through the partial spatial decomposition of the fuel is identified. Significant eliminations (about 80% reduction) in idle cyclic variability are reported through this novel technique.

Two analysis procedures of the crankshaft stress are introduced. One is the conventional method which is very efficient as a model of simple beam at initial design stage within short time. For this analysis bending and torsion are considered as loadcases that are subjected to cyclic variation. The other is the detail Finite Element Analysis which is taken into account of load conditions due to the complex crankshaft dynamic behaviors. From the analysis, the natural frequencies in torsion and bending of the crankshaft as well as with the associated mode shapes and the maximum moments are calculated. The maximum moments are used in FE analysis as loadcases. The model is completed using solid linear elements with some special elements. The application of the FE method for the crankshaft stress analysis has advantage as it directly supplies the locations and level of maximum stresses, even though this method reqiures exact boundary conditions and spending much time in calculation.

A 14 litre turbo charged intercooled diesel engine has been re-engineered to operate as a spark ignition engine fuelled with natural gas. The design targets were for an efficient engine with low emissions using the lean burn capability of natural gas but without sacrificing power output. The resulting ultra lean burn spark ignition engine achieves diesel engine thermal efficiency, with a much reduced NOx emissions though higher NMHC emissions. The engine changes included revised compression ratio, and combustion chamber shape, inlet system modifications to increase turbulence during combustion, i.e., a “smart burn” system, and a new engine management strategy using a “drive by wire” computer control of fuel and throttle and spark timing. The engine has begun duty in an articulated truck in a short haul parts delivery operation, and monitoring of the in service performance has begun.

Stirling Thermal Motors, Inc., (STM) of Ann Arbor, Michigan, has been developing a general purpose Stirling engine designated the STM4-120.* The configuration of the STM4-120 was based on the Ford/Philips automotive Stirling engine which was successfully demonstrated in a 4500 pound Ford Torino in 1976. This engine, designated the 4-215, was a four-cycle, double-acting engine with a fixed angle swashplate drive and produced 175 horsepower (128 kW). During the Ford program, three obstacles to mass production were identified: the complexity of the mean pressure power control, the life and reliability of the rod seals, and the complex geometry and manufacturability of the heater heads. In the conceptual design phase of the STM4-120, effort was concentrated on addressing and overcoming these obstacles.

A computer simulation program has been developed for predicting the performance and emission of a multi-cylinder turbocharged gasoline engine. The two-zone expansion model and the method of characteristics were adopted to evaluate the properties of the gas in the cylinder and pipe respectively. The flow through the turbine and compressor was calculated by using the characteristic charts. To predict exhaust emission, twelve species were considered to be present in combustion products, and the concentrations of these species were calculated through equilibrium thermodynamics and kinetic theory. The simulation models were selected not to depend much on the empirical constants. For the indispensable empirical constants, the easy ways of their determination were suggested.

This is an assessment of current two-stroke automotive engine technology, implementation policy, vision, goals, and engine development and commercialization strategy. It includes a historical review of key two-stroke Otto cycle engine developments, a summary of the specifications for the new: Suburu Super 2-stroke, Toyota S-2 gasoline engine, Orbital two-stroke, General Motors GMCDS2 two-stroke engine and Industrial Technology Research Institute (ITRI) two-stroke engine test technology in Taiwan. Although two-stroke engine technology has been under development since the end of the 19th century, currently the only mass produced vehicles powered by two-stroke cycle engines are the Trabant and Wartburg, with 594 cc two cylinder and 993 cc three cylinder engines, respectively, essentially unchanged in cylinder configuration and porting since 1931.

The flow characteristics such as flow coefficient and swirl ratio in cylinder were measured at steady-state condition by using a steady-state flow measuring system which consists of an impulse swirl meter and a viscous flow air meter. Effects of the in-cylinder swirl on the emissions (NOx, THC), BSFC, MBT, and lean mixture limit (LML) were investigated by using single cylinder research engine with a helical intake port. The combustion pressure in the cylinder was measured to analyze the combustion duration (such as the initial burn duration and the main burn duration) and COV of IMEP which have an effect on LML. By generating the in-cylinder swirl, the combustion duration is remarkably decreased, while the emissions and BSFC are increased. The lean mixture limit is increased with the in-cylinder swirl ratio. In the case of high swirl ratio (Rs=2.48),the lean mixture limit is increased by 3.3 with optimized fuel inject ion timing.

Increased power outputs in high performance diesel engines are being obtained by the use of increased boost pressures obtained from the engine's turbochargers. Reduced compression ratio because of high boost tends to cause cold starting problems and white smoke at idle and light load, especially with a cold engine. One method of alleviating these problems is to make use of glow plugs in the engine cylinders. Applications of glow plugs include a glow plug ignited natural gas engine, methanol DI engine, and IDI and DI diesel engines. This paper describes a glow plug control system that actually controls the glow plug temperature directly. This new control system is better than the systems currently fitted to IDI diesel vehicles. The glow plug controller maintains a constant temperature at the glow plug without the use of any sensor external to the glow plug.

Numerical calculation based on finite element method are carried out to calculate the temperature field in an adiabatic diesel engine piston having diameter. 127 mm and made of aluminum alloy. The engine cylinder wall have the coated externally by a thin layer of very high grade ceramic insulating material. The isothermic distribution in the piston body and the heat flow rates to the cooling media at different loads have been depicted for both cases with and without insulation coating. The paper first reviews the current state of development of ‘adiabatic’ diesel engine in Europe, U.S.A and the Japan. This review section is followed by a brief description of the common element of hostile features, then comes the experimental program on thermally insulated components for single cylinder engine in the research center of Tabriz and finally by a theoretical section dealing with the performance potential of composed engine schemes based on ‘adiabatic’ engine operation.

This paper introduces the friction sphere concepts to consider the effects of friction in the spherical joint and presents a new effective numerical solution method for the analysis of multibody systems with spherical joint under Coulomb friction. Complete equations of motion and reaction forces are derived for dynamic analysis of multibody systems by using Lagrangian formulation. The numerical solutions of the new method are illustrated by its applications to the variable displacement car air conditioning compressor, which has five pistons connected to the wobble plate by five actuating rods with spherical joints at both ends. The new method successively accomplishes the solutions of the equations of motion and reaction forces of the compressor in less computing time than the conventional method.