IC Engine performance parameters:
IC Engine performance parameters help to find out the various types of efficiencies like thermal efficiency, mechanical efficiency, relative efficiencies, power, volumetric efficiency, brake power, indicated power, friction power, etc.
First Law Analysis Of IC Engine:
We know in internal combustion engine the chemical energy of the fuel which actually calculated in terms of calorific value, that chemical energy o fuel goes into combustion and from combustion pressure is created and that pressure is applied on the piston and that from the piston pressure goes to the crankshaft and from crankshaft we get the output.
Fig:
When the fuel will burn in the combustion chamber then the pressure and the temperature inside will increase because of the high pressure and temperature inside, this pressure force is applied to the piston and we get the work as the output which is called as Power displacement work.
Indicated Power:
The power obtained on the top of the piston after the fuel burn is called indicated power.
Brake power or Shaft Power:
Fuel power gets converted into indicated power and indicated power eventually converted into Brake power or shaft power.
Fuel Power:
To calculate the fuel power= Mass flow rate of fuel* Calorific valve.
Friction power:
Indicated power-Brake power= friction power
Internal Combustion engine efficiencies:
Indicated thermal Efficiency = Indicated power/fuel power * 100
Brake Thermal Efficiency= Brake power/fuel power * 100
Mechanical efficiency= Brake power/indicated power * 100
Relative Efficiency= Thermal efficiency/air standard efficiency.
Air Standard efficiency are otto, diesel cycle eficiency.
Volumetric efficiency= Actual volume suction/swept volume = Va/Vs.
