Specific heat (often denoted as “C”) is a property of a substance that describes its ability to absorb or release heat energy when its temperature changes. It is typically measured in joules per kilogram per degree Celsius (J/kg°C) or in calories per gram per degree Celsius (cal/g°C).
Cp is the amount of heat required to raise the temperature of a unit mass of a substance by 1 degree Celsius while keeping the pressure constant. Mathematically, it can be expressed as:
Cp=Q/(m*ΔT)
where,
- Cp is the specific heat at constant pressure (in J/kg°C)
- Q is the heat energy absorbed or released (in joules)
- ΔT is the change in temperature (in degrees Celsius) =T2-T1
The specific heat of a substance can vary with temperature, so sometimes you might see specific heat expressed as a function of temperature. In such cases, you would use an integral to calculate the heat transfer over a temperature range.
Specific heat is a fundamental property of the working fluid that influences the performance and efficiency of propulsion systems, and it is often used in conjunction with other thermodynamic properties and equations to analyze and design these systems.