The heat capacity ratio compares constant-pressure and constant-volume heat capacities.
Difficulty
Intermediate
Read time
4 min
Prerequisites
Consistent SI units, algebra, and the physical assumptions listed below
Source
Teng-Jui Lin — Equation SheetsAdapted from Teng-Jui Lin, Equation Sheets — Mechanical Engineering, under CC BY 4.0.
Adapted notation and added original explanations, variables, assumptions, applications, and a worked example.
The heat capacity ratio compares constant-pressure and constant-volume heat capacities. It appears in ideal-gas isentropic relations and sound-speed formulas, but treating it as constant requires a temperature range over which the heat capacities vary little.
| Symbol | Meaning | Units |
|---|---|---|
| Heat capacity ratio | ||
| Specific heat at constant pressure | ||
| Specific heat at constant volume |
Supply the exponent for an appropriate ideal-gas compression or expansion.
Provide a heat-capacity ratio for an ideal-gas sound-speed estimate.
A gas model has c_p = 1005 and c_v = 718 J/(kg·K). Find γ.
Adapted from Teng-Jui Lin, Equation Sheets — Mechanical Engineering, under CC BY 4.0.
Adapted notation and added original explanations, variables, assumptions, applications, and a worked example.
Assumptions
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