# Mechanical Engineering - Thermodynamics - Discussion

Discussion Forum : Thermodynamics - Section 1 (Q.No. 8)
8.
Which of the following represents Otto cycle on temperature - entropy (T - s) diagram?
Explanation:
No answer description is available. Let's discuss.
Discussion:
34 comments Page 1 of 4.

O.rakesh said:   4 years ago
process 1-2 is adiabatic compression so temperature increases constantly.
(2)

Raghwendra said:   5 years ago
The number sequence is wrong. Process 1 to 2 is isentropic compression. That means pressure and temperature will increase.

Ragu said:   5 years ago
This is not a correct representation, for T-s of an Otto process 1-2 isentropic compression starts from low temp to high.

Mahesh said:   5 years ago
Otto cycle is consist of two constant volume process.

Ramachandra h c said:   6 years ago
Addition of heat takes place in Otto cycle during constant volume process.

Sushant said:   7 years ago
It is a wrong diagram.

Process 1 to 2 is compression process so temp will always increase rather than decrease.

Amarjeet kumar said:   7 years ago
In Otto cycle, the combination of 4 reversible cycle 2 isentropic and 2 constant volume process in this process heat addition is constant volume and heat rejection at constant volume.

Hence in this figure, the correct answer is c.

Dr O.A. Adeaga said:   7 years ago
Option C is the correct answer.

But it's more logical and traditional that reversible adiabatic compression (isentropic compression) commences the cycle while heat addition at constant volume (isochoric heat addition) follows before adiabatic expansion (isentropic expansion) and the cycle ends with constant volume heat rejection (isochoric heat rejection).

Thanks.

Manojkumar.s.g said:   7 years ago
Otto cycle consists of two isentropic process and two constant volume process.

Nabakrushna said:   7 years ago
Otto cycle works on constant volume and 2 isentopic process.