Marine Engineering

OTTO CYCLE An Otto cycle is an idealized thermodynamic cycle that describes the functioning of a typical spark ignition piston engine or a petrol engine. It is the thermodynamic cycle most commonly found in automobile engines using petrol or gasoline fuel. Process 0–1: Constant Pressure A mass of air (working fluid) is drawn into the cylinder, from 0 to 1, at atmospheric pressure (constant pressure) through the open intake valve, while the exhaust valve is closed during this process. The intake valve closes at point 1. Process 1-2: Isentropic compression In this process, the piston moves from bottom dead centre(BDC) to top dead centre (TDC) position. Air undergoes reversible adiabatic isentropic compression.We know that compression is a process in which volume decreases and pressure increases. Hence, in this process, volume of air decreases fromV1 to V2 and pressure increases from P1 to P2. Process 2-3: Constant Volume Heat Addition Process 2-3 is ...