Performance analysis of turbocharger effect on engine in local cars

The performance of a gasoline-fueled internal combustion engines can be increased with the use of a turbocharger. However, the amount of performance increment for a particular engine should be studied so that the advantages and drawbacks of turbocharging will be clarified. This study is mainly concerned on the suitable turbocharger unit selection, engine conversions required and guidelines for testing a Proton 4G92 SOHC 1.6-litre naturally aspirated gasoline engine. The engine is tested under its stock naturally aspirated condition and after been converted to turbocharged condition. The effect of inter cooled turbocharged condition is also been tested. Boost pressure is the main parameter in comparing the performance in different conditions as it influences the engine torque, power, efficiency and exhaust emissions. The use of a turbocharger on this test engine has clearly increased its performance compared to its stock naturally aspirated form. The incorporation of an intercooler to the turbocharger system increases the performance even further. With the worldwide effort towards environmental-friendly engines and fossil fuel shortage, the turbocharger can help to create engines with enhanced performance,minimum exhaust emissions and maximum fuel economy

Effect of thermo-physical properties of cooling mass on hybrid cooling for lithium-ion battery pack using design of experiments

The environmental and sustainability issues related to fossil fuel have made electric vehicles an alternative solution with lithium ion (Li-Ion) as the energy source. The sensitive nature of Li-Ion batteries has led to an active research on their thermal management for the past decade. The rise in temperature in Li-Ion batteries involves complex dynamics and there are several approaches to control it. Keeping it as the focus of research, this paper illustrates the application of design of experiments (DOE) to optimize the control variables involved in thermal management. Control variables used for optimization are mass of phase change material (PCM), thermal conductivity of paraffin copper composite (PCC) and water flow rate (WFL). The influence of these variables on the temperature rise of Li-Ion batteries has been studied. The research methodology involved full factorial DOE with two replications to analyze the influence of temperature control parameters of Li-Ion batteries. Multivariate analysis involved analysis of variance (ANOVA) that was used to test the hypotheses, which included the first and second-order interaction effect of control variables. The hypothesis testing has revealed that all the variables of study had a significant influence on the temperature rise of the Li-Ion batteries. The outcome of this research will be useful for Li-Ion battery manufacturers, as it provides suggestions to design appropriate cooling systems for the battery pack

A boil-off gas utilization for improved performance of heavy duty gas turbines in combined cycle

The storage of the natural gas under liquid phase is widely adopted and one of the intrinsic phenomena occurring in liquefied natural gas is the so-called boil-off gas; this consists of the regasification of the natural gas due to the ambient temperature and loss of adiabacity in the storage tank. As the boil-off occurs, the so-called cold energy is released to the surrounding environment; such a cold energy could potentially be recovered for several end-uses such as cooling power generation, air separation, air conditioning, dry-ice manufacturing and conditioning of inlet air at the compressor of gas turbine engines. This paper deals with the benefit corresponding to the cooling down of the inlet air temperature to the compressor, by means of internal heat transfer recovery from the liquefied natural gas boil-off gas cold energy availability. The lower the compressor inlet temperature, the higher the gas turbine performance (power and efficiency); the exploitation of the liquefied natural gas boil-off gas cold energy also corresponds to a higher amount of air flow rate entering the cycle which plays in favour of the bottoming heat recovery steam generator and the related steam cycle. Benefit of this solution, in terms of yearly work and gain increase have been established by means of ad hoc developed component models representing heat transfer device (air/boil-off gas) and heavy duty 300 MW gas turbine. For a given ambient temperature variability over a year, the results of the analysis have proven that the increase of electricity production and efficiency due to the boil-off gas cold energy recovery has finally yield a revenue increase of 600,000€/year

Current Issues and Problems in the Joining of Ceramic to Metal

Ceramics and metals are two of the oldest established classes of technologically useful materials. While metals dominate engineering applications, ceramics have some attractive properties compared to metals, which make them useful for specific applications. The properties of individual ceramics and metals can vary widely; however, the characteristics of most materials in the two classes differ significantly. Joints between a metal and ceramic are becoming increasingly important in the manufacturing of a wide variety of technological product. But joining ceramics to metallic materials often remains an unresolved or unsatisfactorily resolved problem. This chapter deals with problems of various studies in recent years on the joining between two materials

Design and development of pumps for power plant and cars

The development of the automobile industry in Malaysia has been very encouraging in the past years. Anyhow, this industry is confined to technology follower rather than technology leader. Thus the purpose of the project is to contribute positively to the whole process of automotive development in Malaysia. The advancement of automobile has continuously demanded more engine power requirement and thus, has increased the thermal load of the cooling system. In response to this, concern has been given to the cooling system efficiency improvement. To understand the effects of cooling system on the performance of the engine, the heat characteristics of cooling system were studied with different cooling temperatures. This range of temperatures, results in variations of engine performance, particularly the engine emission level. Engine hydrocarbon emissions increased as the coolant temperature decreases and therefore the importance of coolant temperature on the engine performance could not be neglected. As for the cooling system study, new cooling pump impellers have been designed. Series of experiments were carried out to determine the performance of the impellers as part of a water pump and also its influence to the engine performance. The new impellers produced 17% increase in the water pump efficiency. Since cooling water pump is operated by the engine itself, the efficiency improvement will therefore increase the engine efficiency by 6% or approximately 0.85kW in power gain for a 1.5 litre engine. Manufacturing study was also carried out to ensure the cost of the new impellers is within the marketing value, thus to improve its demand over conventional impeller

Experimental and numerical investigation on flow angle characteristics of an automotive mixed flow turbocharger turbine

To date, turbocharger remains as a key enabler towards highly efficient Internal Combustion Engine. Although the first turbocharger was patented more than 30 years ago, the design is still being improved, thus signifying its importance in modern vehicles. One of the key features that contribute to the challenges in designing highly efficient turbine is the complex nature of the flow field within the turbine stage itself. Experimental method could be used to extract parameters such as pressure and temperature traces but still unable to provide a full description of the flow field. Therefore, the use of Computational Fluid Dynamics (CFD) in resolving this issue is necessary. Out of many feature of fluid flow in turbomachinery, the flow angle at rotor inlet plays significant role in determining turbine efficiency. However, due to geometrical complexity, even at optimum averaged incidence flow angle, there still exist variations that could impair the turbine ability to produce work. This research attempts to provide insight on the complexity of flow angle distribution within the turbocharger turbine stage. To achieve this aim, a numerical model of a full stage turbocharger turbine operating at 30000rpm under its optimum condition was developed. Results indicated that even though use of guide vanes has reduced flow angle fluctuations at mid-span of the rotor inlet from ±10° to only ±1°, significant variations still exist for velocity components in spanwise direction. This in turns effected the distribution of incidence flow angle at the rotor leading edge. In the current research, variation of incidence flow angle in spanwise direction is recorded to be as high as 60

An investigation of volute cross-sectional shape on turbocharger turbine under pulsating conditions in internal combustion engine

Engine downsizing is a proven method for CO2 reduction in Internal Combustion Engine (ICE). A turbocharger, which reclaims the energy from the exhaust gas to boost the intake air, can effectively improve the power density of the engine thus is one of the key enablers to achieve the engine downsizing. Acknowledging its importance, many research efforts have gone into improving a turbocharger performance, which includes turbine volute. The cross-section design of a turbine volute in a turbocharger is usually a compromise between the engine level packaging and desired performance. Thus, it is beneficial to evaluate the effects of cross-sectional shape on a turbine performance. This paper presents experimental and computational investigation of the influence of volute cross-sectional shape on the performance of a radial turbocharger turbine under pulsating conditions. The cross-sectional shape of the baseline volute (denoted as Volute B) was optimized (Volute A) while the annulus distribution of area-to-radius ratio (A/R) for the two volute configurations are kept the same. Experimental results show that the turbine with the optimized volute A has better cycle averaged efficiency under pulsating flow conditions, for different loadings and frequencies. The advantage of performance is influenced by the operational conditions. After the experiment, a validated unsteady computational fluid dynamics (CFD) modeling was employed to investigate the mechanism by which performance differs between the baseline volute and the optimized version. Computational results show a stronger flow distortion in spanwise direction at the rotor inlet with the baseline volute. Furthermore, compared with the optimized volute, the flow distortion is more sensitive to the pulsating flow conditions in the baseline volute. This is due to the different secondary flow pattern in the cross-sections, hence demonstrating a direction for desired volute cross-sectional shape to be used in a turbocharger radial turbine for internal combustion engine

Turbocharger matching method for reducing residual concentration in a turbocharged gasoline engine

In a turbocharged engine, preserving the maximum amount of exhaust pulse energy for turbine operation will result in improved low end torque and engine transient response. However, the exhaust flow entering the turbine is highly unsteady, and the presence of the turbine as a restriction in the exhaust flow results in a higher pressure at the cylinder exhaust ports and consequently poor scavenging. This leads to an increase in the amount of residual gas in the combustion chamber, compared to the naturally-aspirated equivalent, thereby increasing the tendency for engine knock. If the level of residual gas can be reduced and controlled, it should enable the engine to operate at a higher compression ratio, improving its thermal efficiency. This paper presents a method of turbocharger matching for reducing residual gas content in a turbocharged engine. The turbine is first scaled to a larger size as a preliminary step towards reducing back pressure and thus the residual gas concentration in-cylinder. However a larger turbine causes a torque deficit at low engine speeds. So in a following step, pulse separation is used. In optimal pulse separation, the gas exchange process in one cylinder is completely unimpeded by pressure pulses emanating from other cylinders, thereby preserving the exhaust pulse energy entering the turbine. A pulse-divided exhaust manifold enables this by isolating the manifold runners emanating from certain cylinder groups, even as far as the junction with the turbine housing. This combination of appropriate turbine sizing and pulse-divided exhaust manifold design is applied to a Proton 1.6-litre CamPro CFE turbocharged gasoline engine model. The use of a pulse-divided exhaust manifold allows the turbine to be increased in size by 2.5 times (on a mass flow rate basis) while maintaining the same torque and power performance. As a consequence, lower back pressure and improved scavenging reduces the residual concentration by up to 43%, while the brake specific fuel consumption improves by approx. 1%, before any modification to the compression ratio is made

Performance enhancement of horizontal extension and thermal energy storage to an abandoned exploitation well and satellite LNG station integrated ORC system

Tens of millions of abandoned exploitation wells (AEW) exist throughout the world, posing a threat to the environment and costing extra investment for decommissioning. Revitalization of the AEW offers a cost-effective solution for geothermal energy exploitation by saving the high costs of decommissioning and drilling. However, the thermal resources from AEW are usually of low and medium grade. Measures should be taken to increase the efficiency of AEW geothermal power plants. Meanwhile, the regasification process of satellite liquified natural gas (LNG) stations worldwide suffer from a loss of high-grade cold energy. Various studies have used geothermal heat and LNG cold to produce electricity, yet the horizontal extension of the AEW that may increase the recovered temperature, and the fluctuation of the LNG flow that may reduce the power output, were not discussed. This study proposes and evaluates a novel integrated organic Rankine cycle (ORC) system that uses the geothermal heat from the AEWs and waste LNG cold energy from satellite LNG stations, focusing on the performance enhancement of horizontal extension to increase the geothermal temperature and thermal energy storage to stabilize the LNG cold energy supply. A numerical model is developed that considers the horizontal extension in the AEW, and the horizontal extension is found to significantly increase the geothermal fluid temperature. A machine learning-based predictive model is built to assess the AEW outlet temperature under given parameters and working conditions. Cold thermal energy storage (CTES) modules are designed and optimized to stabilize the waste cold energy recovery when exposed to highly fluctuating LNG supply during off-design operation. CTES increased the ORC efficiency by 38.5% and has the potential to significantly shorten the payback period. Therefore, by utilizing the horizontal extension of the AEW and combining the power generation with LNG cold through thermal energy storage, the zero-emission geothermal and waste cold energy-based system can be a viable solution for future AEW revitalization and LNG waste cold energy utilization

Automotive turbocharging

The future trends of automotive engine are universally toward down-sizing, higher power density and above all lower carbon emissions. Among many technologies revolutionizing automotive development, turbocharging is considered as a significant enabler to meet the ever increasing future demands. Uchida (2006) provided a good discussion on the future trends for the automotive industry and the inherent role of turbocharging, with focus on the Toyota research developments. Figure 1.1 shows the demand for specific power to increase to 70 kW/l and CO2 emission to reduce to 115 kg/km by the year 2010. Achieving the goal, according to Uchida (2006), will need technological steps forward with turbocharging enhancement as the main player. These views are also shared by Shahed (2005) in his article discussing the general demand and importance of turbocharging for the current and future automotive power train. Down-sizing and emission reduction were the main driving force behind the significant development of turbo diesels in Europe and similar development are predicted for the United States automotive industry