Psychrometric chart and constant enthalpy lines

Psychrometric chart is a graphical representation of the thermodynamic properties of moist air. It is used to determine the various properties of air like dry bulb temperature, wet bulb temperature, relative humidity, dew point temperature, and enthalpy.

Constant wet bulb temperature lines

Constant wet bulb temperature lines on the psychrometric chart are the lines that connect the points of equal wet bulb temperature. These lines are important for determining the specific humidity of the air, which is the mass of water vapor per unit mass of dry air.

Constant enthalpy lines

Constant enthalpy lines on the psychrometric chart are the lines that connect the points of equal enthalpy. Enthalpy is the amount of heat energy stored in the air, and it is the sum of the sensible and latent heat. The constant enthalpy lines on the chart help in determining the heat transfer in air conditioning systems.

Coincidence of constant wet bulb temperature and constant enthalpy lines

The constant wet bulb temperature lines coincide with the constant enthalpy lines on the psychrometric chart. This is because both wet bulb temperature and enthalpy are thermodynamic properties of moist air that are interdependent.

When air is cooled at a constant pressure, its enthalpy decreases, and so does its wet bulb temperature. Similarly, when air is heated at a constant pressure, its enthalpy increases, and so does its wet bulb temperature. Therefore, the constant wet bulb temperature lines and the constant enthalpy lines on the psychrometric chart coincide with each other.

Conclusion

In conclusion, the constant wet bulb temperature lines and the constant enthalpy lines on the psychrometric chart coincide with each other. This is because wet bulb temperature and enthalpy are interdependent thermodynamic properties of moist air. The coincidence of these lines is important in determining the specific humidity and heat transfer in air conditioning systems.