https://bura.brunel.ac.uk/bitstream/2438/15625/1/Fulltext.pdf

Application of Micro Gas Turbine in Range-Extended Electric Vehicles

Experimental investigation of the influence of internal and external EGR on the combustion characteristics of a controlled auto-ignition two-stroke cycle engine

In this study the influence of utilization of two Waste Heat Recovery (WHR) strategies, namely organic Rankine cycle (ORC) and turbocompounding, have been investigated based on the performance of a heavy-duty diesel engine using 1-D simulation engine code (GT-Power) in terms of Brake Specific Fuel Consumptions (BSFC) at various engine speeds and Brake Mean Effective Pressures (BMEP). The model of a 6-cylinder turbocharged engine (Holset HDX55V) was calibrated using an experimental BSFC map to predict engine exhaust thermodynamic conditions such as exhaust mass flow rate and exhaust temperature under various operating conditions. These engine exhaust conditions were then utilized to feed the inlet conditions for both the ORC and turbocompounding models, evaluating the available exhaust energy to be recovered by each technology. Firstly the ORC system model was simulated to obtain the power that can be generated from the system. Having this additional power converted to useful work, the BSFC was observed to reduce around 2–5% depending upon engine’s speed and BMEP. The initial model of the engine was then modified by considering a second turbine representing turbocompounding heat recovery system. The BSFC was increased due to the back-pressure from the second turbine, but the energy generated from the turbine was sufficient to reduce the BSFC further. However, by application of turbocompounding no improvement in BSFC was achieved at low engine’s speeds. It is concluded that ORC heat recovery system produces a satisfactory results at low engine speeds with both low and high loads whereas at medium and high engine speeds turbocompounding heat recovery system causes higher BSFC reduction.

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A Comparative Study of the Effect of Turbocompounding and ORC Waste Heat Recovery Systems on the Performance of a Turbocharged Heavy-Duty Diesel Engine

This study examines the implementation of a waste heat recovery system on an electric hybrid vehicle. The selected waste heat recovery method operates on organic Rankine cycle principles to target the overall fuel consumption improvement of the internal combustion engine element of a hybrid powertrain. This study examines the operational principle of hybrid electric vehicles, in which the internal combustion engines operates with an electric powertrain layout (electric motors/generators and batteries) as an integral part of the powertrain architecture. A critical evaluation of the performance of the integrated powertrain is presented in this paper whereby vehicle performance is presented through three different driving cycle tests, offering a clear assessment of how this advanced powertrain configuration would benefit under several different, but relevant, driving scenarios. The driving cycles tested highlighted areas where the driver could exploit the full potential of the hybrid powertrain operational modes in order to further reduce fuel consumption.

/pdf/hybrid-electric-vehicle-performance-with-organic-rankine-uaxotwldqq.pdf

Hybrid electric vehicle performance with organic rankine cycle waste heat recovery system

An experimental study on the influence of EGR rate and fuel octane number on the combustion characteristics of a CAI two-stroke cycle engine

A new combustion concept, which is viewed increasingly as a probable solution to these issues is Controlled Auto-Ignition (CAI) Combustion. In such an engine, a homogeneous mixture of air, fuel and residual gases is compressed until auto-ignition occurs. Due to its significantly low temperature combustion, NOx will be dramatically reduced while the mixture will be under ultra-lean fuel-air condition, thus able to achieve high efficiency and low emission. In the case of two-stroke engine, problem of poor combustion efficiency and excessive white smoke emission can be addressed by the incorporation some features that will ultimately convert a typical two-stroke engine into an efficient CAI engine demonstrating the best of both features. Due to its inherent high internal residual gas rate in partial load operation, the two-stroke engine has been the first application to benefit from the unconventional CAI combustion process. This paper will concisely discuss the utilization of hot burned gas for induction thus imposing a CAI combustion feature onto two-stroke cycle engine. Among the features incorporated are the increasing in the level of Exhaust gas Recirculation and cycle-by-cycle uniformity of the air-fuel ratio (AFR) supplied to cylinder, which will be crucial in creating a suitable temperature within the engine’s combustion chamber.

Controlled Auto-Ignition Combustion in a Two-Stroke Cycle Engine Using Hot Burned Gases

This project present an experimental test results on energy consumption of a refrigerator compressor triggered by using thermostat and programmable logic control (PLC). The PLC modulates the speeds of the compressor according to refrigeration load using inverter based on control law written in the PLC memory. The temperature setting for both thermostat and PLC were varied at-8 °C and-10 °C respectively. At-8°C the results indicate PLC consumed 4.45 to 6.79% less energy compared to thermostat setting. While at-10°C, the saving made through PLC is in the range of 6.43 to 12.88%. The fluctuation of freezer compartment is better when PLC controlled. As the energy input to compressor is lower due to the slower speed, this enhanced the coefficient of performance (COP).

Energy analysis and compressor performance of refrigerator system using programmable logic control (PLC)

The use of hydrocarbon gases as a refrigerant has been done before the emergence of CFCs (chlorofluorocarbons) and HCFCs (hydrochlorofluorocarbons). However, because of issues of environmental damage caused by both the gas, namely CFCs and HCFCs, causing the experts try to use environmentally friendly refrigerants, namely hydrocarbons. The hydrocarbon used in this study was a mixture of propane (R290), butane (R600), and isobutane (R600a), and was called HC-22. The air-conditioning was originally to work with refrigerant HCFC-22 and with compressor capacity is 1860 W. Measurements were taken during the experimental period at a time interval of ten minutes for a set point temperature of 20oC. The objective of the research was to compare the refrigeration performance of different refrigerants in terms of a coefficient of performance (COP), refrigeration effect, and power consumption by the compressor. The experimental results showed that the COP, cooling capacity and energy saving of HC-22 higher than that of HCFC-22. The results also indicated that hydrocarbon mixture could be used as a drop-in replacement for split unit of the air conditioning system.

Performansi sistem pendingin split unit dengan menggunakan hcfc-22 dan hc-22

This research is to study the operation of the four-stroke HCCI engine. The design and analysis works have been performed using computer software which is GT-Power and Solidwork to study on the engine performance simulation work and 3-D modelling on the combustion chamber designed respectively. The design is based on 4-cylinder passenger car, 2000 cc and a four-stroke cycle engine. The compression ratio used is 10. The fuel used is ethanol in which the air-fuel ratio (AFR) is 9. The parameters selected have typical range of value based on the previous study and research done. With the use of GT-power, the analysis will consider two parameters which are the cam timing angle and the injection timing angle to get the optimum result for the HCCI engine. The typical angle of cam timing angle is between 2600 – 2700 since this is the moment of the compression cycle of the engine. For the injection timing angles, the angles that will be studied for this project are 50, 00, -50, -100,-150 and -200 relative to Top Dead Centre (TDC). The objective is to obtain the maximum torque and brake power when the engine speed is in between 4000 rpm to 5000 rpm and 6000 rpm to 7000 rpm respectively. Finally, the optimum conditions for the engine to perform better are at 2640 of cam timing angle for the valve and at -50 before TDC for the injection timing angle. The maximum torque and brake power achieved is 37.60 Nm at 4000 rpm and 23.46 kW at 7000 rpm.

Design of a Four-Stroke Homogeneous Charge Compression Ignition Engine

The HFC-R134a and hydrocarbon refrigerant (HCR) will be evaluated on the automotive air conditioning (AAC) experimental test rig which completed with the AAC system including the blower, evaporator, condenser, radiator, electric motor, compressor, alternator and equipped with the simulation room acting (equipped with internal heat load) as the passenger compartment. The electric motor operated as a car’s engine and will drive the compressor simultaneously to the alternator to recharge the battery. The tests have been performed by varying the motor speed; 1000, 2000 and 3000 rpm, temperature set-point; 21 and 230C, and internal heat loads; 0, 500, 700 and 1000 W. The results of the performance characteristics of the HCR indicate the encouraging enhancement of the AAC system compared to Hydrofluorocarbon refrigerant (HFC-R134a).

Abdul Latiff Zulkarnain

Papers

Controlled Auto-Ignition Combustion in a Two-Stroke Cycle Engine Using Hot Burned Gases

Energy analysis and compressor performance of refrigerator system using programmable logic control (PLC)

Performansi sistem pendingin split unit dengan menggunakan hcfc-22 dan hc-22

Design of a Four-Stroke Homogeneous Charge Compression Ignition Engine

Experimental Study on the Replacement of HFC-R134a by Hydrocarbons in Automotive Air Conditioning System