Zulkarnain Abdul Latiff

Analysis of Variable Intake Runner Lengths and Intake Valve Open Timings on Engine Performances

In this paper, engine simulation tool is used to investigate the effect of variable intake manifold and variable valve timing technologies on the engine performance at full load engine conditions. Here, an engine model of 1.6 litre four cylinders, four stroke spark ignition (SI) engine is constructed using GT-Power software to represent the real engine conditions. This constructed model is then correlated to the experimental data to make sure the accuracy of this model. The comparison results of volumetric efficiency (VE), intake manifold air pressure (MAP), exhaust manifold back pressure (BckPress) and brake specific fuel consumption (BSFC) show very well agreement with the differences of less than 4%. Then this correlated model is used to predict the engine performance at various intake runner lengths (IRL) and various intake valve open (IVO) timings. Design of experiment and optimisation tool are applied to obtain optimum parameters. Here, several configurations of IRL and IVO timing are proposed to give several options during the engine development work. A significant improvement is found at configuration of variable IVO timing and variable IRL compared to fixed IVO timing and fixed IRL.

A Converted Two-Stroke Cycle Engine for Compression Ignition Combustion

A new kind of alternative combustion concept that has attracted attention intensively in recent years is called controlled auto-ignition (CAI) combustion. CAI combustion has been proposed and partially implemented with the aim of both improving the thermal efficiency of internal combustion engines, achieving cleaner exhaust emissions and lower cyclic variation. An experimental study is conducted through a CAI two-stroke cycle engine in order to investigate the influence of internal exhaust gas recirculation (In-EGR) and external exhaust gas recirculation (Ex-EGR) variation in relation to combustion cyclic variability and exhaust emissions characteristics. Results implied that cyclic variation of both combustion-related and pressure-related parameter is substantially improved. Furthermore remarkable decreased exhaust emissions, unburned hydrocarbon (uHC), carbon monoxide (CO) and nitric dioxide (NOX), was observed.

Retrofitting R-22 split type air conditioning with hydrocarbon (HCR-22) refrigerant

An experimental study to evaluate the energy consumption of a split type air conditioning is presented. The compressor works with the fluids R-22 and HCR-22 and has been tested varying the internal heat load 0, 500, 700 and 1000 W. The measurements taken during the one hour experimental periods at 10-minutes interval times for temperature setpoint of 20oC. The performance data considered where the evaporator cooling load, the condenser heat rejection, the electrical energy consumption, the refrigeration system temperatures, and the room temperature. And hence the Coefficient of Performance (COP) could be determined. The final results of this study show an overall better energy consumption of the HFC-22 compared with the R-22.

Experimental evaluation of automotive air-conditioning using HFC-134a and HC-134a

An experimental study to evaluate the energy consumption of an automotive air conditioning is presented. In this study, these refrigerants will be tested using the experimental rig which simulated the actual cars as a cabin complete with a cooling system component of the actual car that is as the blower, evaporator, condenser, radiators, electric motor, which acts as a vehicle engine, and then the electric motor will operate the compressor using a belt and pulley system, as well as to the alternator will recharge the battery. The compressor working with the fluids HFC-134a and HC-134a and has been tested varying the speed in the range 1000, 1500, 2000 and 2500 rpm. The measurements taken during the one hour experimental periods at 2-minutes interval times for temperature setpoint of 20°C with internal heat loads 0, 500, 700 and 1000 W. The final results of this study show an overall better energy consumption of the HFC-134a compared with the HC-134a.

Torrefaction of densified empty fruit bunches with addition of plastics waste

ABSTRACT The techniques of briquetting and torrefaction were applied to a mixture of pulverized empty fruit bunches (EFB) and shredded high-density polyethylene (HDPE) plastics with a weight ratio of 85:15. The briquettes, produced under controlled conditions, were torrefied at various torrefaction temperatures from 225 to 300°C for 30 min with a constant nitrogen flow rate of 1 L/min. The results indicate that the moisture content is reduced and calorific value is significantly improved due to torrefaction treatment. In addition, the compressive strength of the torrefied briquettes is also enhanced by the torrefaction treatment, thus revealing the important role of HDPE plastics as a good binding agent after the treatment. However, the density of the torrefied briquettes decreased with an increase in temperature. The ash content of the briquettes torrefied at 225 to 275°C can be considered competitive if compared to that of conventional solid fuels (< 5.8%). The physical and combustion properties of the torrefied briquettes are strongly affected by torrefaction temperature and mixture composition. Meanwhile, torrefaction at 300°C is not favourable due to significant physical degradation. HIGHLIGHTS Densification and torrefaction were performed on pulverized EFB. Fixed operating conditions were used to produce all briquettes. Addition of HDPE plastics improves the physical and combustion properties. Torrefaction temperature is the most important parameter. Torrefaction temperature at 300°C is not favourable due to physical destruction.

Investigation of Intake Valve Strategy on the Cylinder Deactivation Engine

There are many technologies that being developed to increase the efficiency of internal combustion engines as well as reducing their fuel consumption. In this paper, the main research area is focus on cylinder deactivation (CDA) technology. CDA mostly being applied on multi cylinders engines. CDA has the advantage in improving fuel consumption by reducing pumping losses at part load engine conditions. Here, the application of CDA on 1.6L four cylinders gasoline engine was studied. One-dimensional (1D) engine modeling is performed to investigate the effect of intake valve strategy on engine performance with CDA. 1D engine model is constructed according to the 1.6L actual engine geometries. The model is simulated at various engine speeds at full load conditions. The simulated results show that the constructed model is well correlated to measured data. This correlated model used to investigate the CDA application at part load conditions. Also, the effects on the in-cylinder combustion as well as pumping losses are presented. The study shows that the effect of intake valve strategy is very significant on engine performance. Pumping losses is found to be reduced, thus improving fuel consumption and engine efficiency.

A Review on Butanol and Ethanol Fuels in Internal Combustion Engines

A controversial argument about alternative fuels is taking lots of researchers and scientists attention and so far ethanol and butanol, regardless their blending percentage, are the most promising alcohols due to their potential properties and low production cost. Many studies have been conducted to justify the optimum fuel to be implemented. In this work, a review will be conducted on both butanol and ethanol in internal combustion engine as well as their contribution in combustion engine regarding combustion performance, pollutant emission, ignition timing and knocking. According to the previous literature, an attractive advantage for alcohol-gasoline blends is that they don’t require engine modification design and still reduce the pollutant emission effectively. The properties of these fuels seem to prove not only that we can run our engines with a reduction of pollutant gases but with the emission of greenhouse gasses. This work will provide a review on ethanol and butanol as an alternative fuels and their properties and behaviour in the engine will be described individually.

Driving efficiency through hydrocarbon for green car air conditioning

The feasibility of hydrocarbon mixtures to replace HFC-R134a in automotive air conditioning systems is investigated in this paper. The temperature distribution in car cabin and fuel consumption are evaluated at various passenger load and vehicle speeds using hydrofluorocarbons refrigerant (HFC-R134a) and hydrocarbon refrigerant as the working fluid of the compressor. The experiments are tested in an actual petrol engine vehicle on a roller dynamometer to simulate actual vehicle on level road. The experiments are conducted at the same surrounding conditions. The test has performed by varying the vehicle speed; 50, 70, 90 and 110 kph, and number of passengers; 1 and 2, at temperature set-point of 21°C. The result shows that the hydrocarbon mixtures provide excellent temperature distribution and fuel conservation effect is about 2.95% to 11.90%. In addition, the results support the possibility of using hydrocarbon mixtures as an alternative to HFC-R134a in the automotive air conditioning system, without the necessity of changing parts in the current system.

The effect of fuel additives on gasoline heating value and spark ignition engine performance: Case study

Today fuel additives had been used widely for the enhancement of fuel economy and engine performance. Fuel additives are substance that acts as catalysts for the completeness combustion of fuel in order to increase the heat released and hence the work output will be improved. The purpose of this paper is to investigate the effect of the additives on fuel heating value and engine performance. In this study, three different additives available in the market have been chosen to determine the effect on heating value and engine performance when mixed with fuel. Two types of test were conducted, namely the calorific value and engine performance test. The first test was conducted using a bomb calorimeter with test method in accordance with the DIN 51900 and ASTM D240. The later test was done using engine test bed and with the agreement of BS 5514 (Parts 1 to 6), Reciprocating Internal Combustion Engines: Performance, and SAE 1349 Standard Engine Power Test Code. The study shows that fuel additives can cause a standard fuel to have higher heating value up to 5%. As for the engine performance, the engine brake thermal efficiency and brake mean effective pressure were increased up to 8% and 10% respectively. The specific fuel consumption can be reduced up to 9%.

Dimensional Accuracy Evaluation of Rapid Prototyping Fused Deposition Modeling Process of FDM200mc Machine on Basic Engineering Profiles

The purpose of this research is to study the accuracy of RP FDM Process. This research involves varying two parameters in building up the prototype which is the buildup angle and the sparse for each layer (volume of parts). The varying parameters were used in the FDM process for three types of specimen (profiles) which is the Cube, Cylinder and Pyramid. The varying parameters are the build up angle of 300, 650 and 900 and for the types of sparse, there are three types of sparse used which is Low Density (LD), High Density (HD) and Solid Type. The results of the dimensional accuracy are analyzed by calculating the percentage of difference of the dimensional measurement for the specimen and the actual dimension of it. The lesser difference, the better the dimensional accuracy. The conclusion of this study is the less complicated specimen shape for the FDM process, the more accurate of the dimensional accuracy with the optimum build up angle of 300 or less and the optimum type of sparse of Low Density Type (LD).