Specific heat capacity of moist air
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What is the specific heat capacity of moist air? Urgently needed for work, thank you
Need it urgently. Dear sea friends, please help! Thanks first
Are you trying to calculate the heat load, OP? You can calculate the heat load for air and water vapor separately. When calculating, taking the state into account and adding the latent heat of water vapor completes the process. If you try to look it up, I’m afraid it won’t be in the manual. It can only be known through software simulation. The parameters required are probably air pressure, air temperature, and water vapor humidity.
Right. If I explain the situation in more detail, will that help with the selection? The specific known data are as follows: Air is preheated using the flue gas from the heat treatment furnace. The flue gas inlet temperature is around 500 degrees, with a flow rate of 11,000 cubic meters per hour. The inlet air is at room temperature, the outlet temperature is 300 degrees, and the flow rate is 5900 cubic feet per hour. I wonder if these given conditions are sufficient? I choose a shell-and-tube heat exchanger; please calculate the heat exchange area. Thank you. I hope the calculation steps can be more detailed
The specific heat capacity of moist air is defined as the amount of heat that must be absorbed or released to raise or lower the temperature of (1+H) kg of moist air by 1°C, per unit mass of dry air. It is denoted as cH, with units of kJ/(kg of dry air·K). The formula for cH is cH = ca + cvH, where ca is the specific heat capacity of dry air, in kJ/(kg·K), and cv is the specific heat capacity of water vapor, also in kJ/(kg·K). Within typical temperature ranges, ca ≈ 1.01 kJ/(kg·K) and cv ≈ 1.88 kJ/(kg·K). Substituting these values into the formula gives cH = 1.01 + 1.88H. This formula shows that the specific heat capacity of moist air is a function solely of temperature.