Thermodynamics is filled with equations and formulas. Here’s a list of the most important ones you need to do the calculations necessary for solving thermodynamics problems.

• Combustion equations:

• Air-fuel ratio:

• Hydrocarbon fuel combustion reaction:

• Compressibility calculations:

• Compressibility factor Z: Pv = ZRT

• Reduced temperature:

• Reduced pressure:

• Pseudo-reduced specific volume:

• Efficiency equations:

• Thermal efficiency:

• Coefficient of performance (refrigerator):

• Coefficient of performance (heat pump):

• Energy equations:

• Entropy equations:

• Entropy change for ideal gas, constant specific heat:

• Entropy change for ideal gas, variable specific heat:

• Irreversibility for a process:

• Ideal-gas formulas:

• Ideal-gas law: Pv = RT

• Gas constant:

• Ratio of specific heats:

• Isentropic process for ideal gas:

• Moist air properties:

• Relative humidity:

• Specific humidity:

• Properties of mixtures:

• Quality liquid-vapor mixture:

• Saturated mixture property, y: y = yf + x · yfg

• Work calculations:

• Isobaric process: Wb = P0(V2 – V1)

• Polytropic process:

• Isothermal process of an ideal gas:

• Shaft power:

• Spring work: