Friction power modeling as a function of diesel engine speed and geometry with predicting their effects on some performance parameters

الملخص EN

The first part of the present research is to estimating the relationship between the overall friction power and rotating speed of a 4-stroke single cylinder diesel engine practically by using an electrical motor which was directly connected to the engine with a suitable coupling, and the input power was controlled by using an inverter,(current and volts) were measured by using a digital clamp-meter for different rotating speeds of (600,1200,1800, 2400, 3000 and 3600) rpm.

From the data achieved an equation (polynomial third order) was estimated which represents the friction losses as a function of engine speed.

The estimated equation is used in simulation program (QBASIC ), for predicting the effects of friction on some parameters (power ,efficiency and fuel consumption ) .

The second goal is to developing the estimated equation and using it many cylinders and many displacement volume diesel engines by multiplying it by displacement ratio and number of cylinders.

Finally the results showed good agreement.

Key words :// fraction power ,diesel engine , engine performance ,simulation ,modeling .