Gholamhassan Najafi

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This study deals with artificial neural network (ANN) modeling a diesel engine using waste cooking biodiesel fuel to predict the brake power, torque, specific fuel consumption and exhaust emissions of engine. To acquire data for training and testing the proposed ANN, two cylinders, four-stroke diesel engine was fuelled with waste vegetable cooking biodiesel(More)
To carry out the investigation, a cylinder pressure model was developed based on the position of the crankshaft, engine load, engine speed, and fuel injection time. This model takes into account the maximum number of parameters involved. The accuracy of the model was verified by experimental results. The average error of the cylinder pressure, the average(More)
In this study, the fuel properties and engine performance of blended palm biodiesel-diesel using diethyl ether as additive have been investigated. The properties of B30 blended palm biodiesel-diesel fuel were measured and analyzed statistically with the addition of 2%, 4%, 6% and 8% (by volume) diethyl ether additive. The engine tests were conducted at(More)
Exhaust pollutants from two-stroke petrol engines are a problem for the environment. Biolubricants are a new generation of renewable and eco-friendly vegetable-based lubricants, which have attracted a lot of attention in recent years. In this paper, the applicability of the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method to(More)
Biodiesel is a green (clean), renewable energy source and is an alternative for diesel fuel. Biodiesel can be produced from vegetable oil, animal fat and waste cooking oil or fat. Fats and oils react with alcohol to produce methyl ester, which is generally known as biodiesel. Because vegetable oil and animal fat wastes are cheaper, the tendency to produce(More)
In This research, the effects of biodiesel (from waste cooking oil) in fuel mixture (biodiesel and diesel fuel No.2) on BSFC of a diesel engine. The experiments were conducted on a four cylinder direct-injection diesel engine. Results showed that the use of biodiesel BSFC increases 18 to 24% by the using net biodiesel. Also results showed that the reduction(More)
This study deals with artificial neural network (ANN) modeling of a spark ignition engine to predict engine thermal balance. To acquire data for training and testing of ANN, a fourcylinder, four-stroke test engine was fuelled with ethanol-gasoline blended fuels with various percentages of ethanol and operated at different engine speeds and loads. The(More)
In the current work, a comprehensive study on the possibility of using methanol as an alternative fuel for diesel engines was carried out. Methanol was mixed at different ratios with diesel fuel. The mixing ratios of methanol to diesel were 0:100, 10:90, 20:80 and 30:70. The effects of methanol fraction on engine power, torque, brake specific fuel(More)
In this paper, an efficient procedure for ripeness detection of watermelon was presented. A nondestructive method was used based on vibration response to determine the internal quality of watermelon. The responses of samples to vibration excitation were optically recorded by a Laser Doppler (LD) vibrometer. Vibration data was collected from watermelons of(More)
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