Diesel engine prob

1. Apr 21, 2010

waterboy312

how would you find the correct formula for the temp at state 3 and 4. i found it for 1 and 2

2. Apr 21, 2010

Carlos Dutra

Hello Waterboy.

First, I would ask that when you have a question try to be specific and do not abbreviate the words, because many members here are from different countries and areas.

For an air standard cycle, whose fuel is Diesel:

To calculate the temperature in the cycle expansion (3), it will be the point of greatest pressure and higher temperature, use the formula:

T3 = T2 + (Q1 / (m * cp);

where:

Q1 = heat input
T2 = temperature cycle 2
m = mass
cp = specific heat of gas at constant pressure

To obtain the temperature in the cycle of the removal of heat (4) you must have the values of compression ratio in cycles 3 (V3) and 4 (V4) and the adiabatic constant of air (k), and the temperature in the expansion cycle (3).

T4 = T3 * (V3/V4) ^ (k-1);

where:

T3 = temperature in cycle 3
V3 = volume in the cycle 3
V4 = volume in the cycle 4