Important Trick to remember all Thermodynamic Cycles for Oral Exams

Air Standard Cycle

Cycle Name

Process

Otto Cycle or Constant Volume Cycle

1-2 Isentropic compression 2-3 Constant volume heat addition 3-4 Isentropic expansion 4-1 Constant volume heat rejection

TrickHow bihari would call otto cycle? OttoVA VA constant Volume

Diesel Cycle 1-2 Isentropic compression Trick2-3 Constant Pressure heat Dp addition P- Const 3-4 Isentropic pressure expansion 4-1 Constant volume heat rejection

PV daigram

TS diagram

Cycle Name

Process

Dual Cycle or Semi Diesel Cycle or Limited pressu re cycle

1-2 Isentropic compression 2-3 Constant volume heat addition 3-4Constant Pressure heat addition 4-5 Isentropic expansion 5-1 Constant volume heat re ection

tickDualboth

PV daigram

TS diagram

STIRLING CYCLE

GAS TURBINE

Joules Cycles or Brayton Cycle 1-2 Isentropic compression 2-3 Constant Pressure heat addition 3-4 Isentropic expansion 4-1 Constant Pressure heat rejection

AIR REFRIGERATION CYCLE Bell Coleman Air Refrigeration Cycle / Reverse Brayton Cycle / Reverse Joule Cycle

1-2 Isentropic compression process 2-3 Constant Pressure cooling process 3-4 Isentropic expansion process 4-1 Constant Pressure expansion process

 VAPOUR POWER CYCLES RANKINE CYCLE

How can we increase the efficiency of Rankine Cycle?

CARNOT ENGINE

CARNOT REFRIGERATOR /REVERSE CARNOT CYCLE

DIFFERENCE BETWEEN CARNOT CYCLE

It is a theoretical cycle. It gives maximum efficiency between two temperature difference

Heat is added and rejected at constant temperature.

RANKINE CYCLE This one is a practical cycle of steam engine and turbine.

Heat is added and rejected at constant pressure.

It has highest efficiency between two temperature Rankine cycle has lower efficiency than Carnot differences. cycle. Carnot cycle uses air as the working substance.

Rankine cycle uses water as working substance.

Carnot cycle is ideal cycle for heat engine.

It is ideal cycle for vapor power engine.