Mohd Rozi Mohd Perang

Review on Typical Ingredients for Ammonium Perchlorate Based Solid Propellant

Ammonium perchlorate (AP) based solid propellant is a modern solid rocket propellant used in various applications. The combustion characteristics of AP based composite propellants were extensively studied by many research scholars to gain higher thrust. The amount of thrust and the thrust profile, which may be obtained from a specific grain design, is mainly determined by the propellant composition and the manufacturing process that produces the solid propellant. This article is intended to review and discuss several aspects of the composition and preparation of the solid rocket propellant. The analysis covers the main ingredients of AP based propellants such as the binder, oxidizer, metal fuel, and plasticizers. The main conclusions are derived from each of its components with specific methods of good manufacturing practices. In conclusion, the AP based solid propellant, like other composite propellants is highly influenced by its composition. However, the quality of the finished grain is mainly due to the manufacturing process.

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.

Performance Analysis for Vehicle Air Conditioning System with Direct Current Compressor in Non-Electric Vehicle Using Fuzzy Logic Controller

Reducing fuel consumption and ensure occupants thermal comfort are two important considerations when designing a vehicle air conditioning system. By using direct current electric compressor, speed of compressor can be controlled by changing the frequency of the inverter. Fuzzy logic controller (FLC) was developed to imitate the performance of human expert operators by encoding their knowledge in the form of linguistic rules. The system is installed to a 5-door compact car with 1.2cc four-cylinder engine with data acquisition system to monitor the temperature of the cabin, coefficient of performance (COP) and fuel consumption. Temperature set-point of 22°C with original belt-driven, on/off and FLC electric direct current compressor at one hour experimental periods. The experimental results indicate that the FLC can save more fuel compared to on/off controller and belt-driven compressor.

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.

Impact of the electric compressor for automotive air conditioning system on fuel consumption and performance analysis

Air conditioning system is the biggest auxiliary load in a vehicle where the compressor consumed the largest. Problem with conventional compressor is the cooling capacity cannot be control directly to fulfill the demand of thermal load inside vehicle cabin. This study is conducted experimentally to analyze the difference of fuel usage and air conditioning performance between conventional compressor and electric compressor of the air conditioning system in automobile. The electric compressor is powered by the car battery in non-electric vehicle which the alternator will recharge the battery. The car is setup on a roller dynamometer and the vehicle speed is varied at 0, 30, 60, 90 and 110 km/h at cabin temperature of 25°C and internal heat load of 100 and 400 Watt. The results shows electric compressor has better fuel consumption and coefficient of performance compared to the conventional compressor.

Performance study of electric compressor in non-electric vehicle

The usage of electric compressor inside conventional non-electric vehicle is a new shifts in current vehicle air conditioning system which currently using belt-driven compressor to operate. The usage of belt-driven compressor causes the compressor speed to vary with engine speed rotation, which we cannot control. The usage of electric compressor to replace the belt-driven compressor makes the speed to be according to the cooling load and thus reducing engine load. The current research activity focuses on the development of electric compressor using direct current (DC) from vehicles battery to replace current belt-driven in vehicle air conditioning system. Performance study is focusing on temperature inside cabin, cooling capacity, compressor power consumption and coefficient of performance (COP). The DC compressor speed is varying at 1800, 2000, 2200, 2400, 2500 and 3000 rpm at internal heat load of 1000W with temperature set-point of 20°C. The system uses On/Off controller and compared to belt-driven compressor. The overall experimental results in better energy efficiency at the expense of lower cooling capacity.

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.

Experimental Study on the Performance of In-Cabin Ventilation System

Parking a car under the hot sun with all windows closed could increase in-cabin temperature as high as 70°C. For such situation, human occupancy will exposed to thermal shock and inconvenience when embarking the vehicle. Another concerned of this accumulated heat gain is the effect of gas emitted by the interior material which mostly is made of vinyl. These experimental studies try to look the possibilities of bringing down the temperature and hence to suit human habitation. In this study, two methods were implemented and they are by creating fresh air change and introducing evaporative cooling by generating water mist in the air flow for further enhancement of temperature drop. Fully automated control strategy was used based on in-cabin temperature activation by the assistance of electronic control unit (ECU). Observation was made and compare for original car condition and the one equipped with In-Cabin Ventilation (IVS). The result shows the car cabin temperature can reach as high as 65°C without ventilation. With fresh charged of air and evaporative cooling, temperature drops to a range of 40 to 50°C.

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%.