Final answer:
To calculate the minimum air flowrate required in the cooling tower, you can use the concept of heat transfer through evaporation. By considering the heat transfer rate due to evaporation, you can determine the required air flowrate. The specific enthalpies of the water and air entering and leaving the cooling tower are used in the calculations.
Step-by-step explanation:
The minimum air flowrate required to achieve the cooling can be calculated using the concept of heat transfer through evaporation. In the cooling tower, the warm cooling water is sprayed down from the top, while ambient air is blown into the cooling tower from the bottom. The air and water come in direct contact, causing evaporation and heat transfer. To calculate the minimum air flowrate, you need to consider the heat transfer rate due to evaporation. This can be determined using the heat transfer equation:
Q = m_dot_water * (h_water_in - h_water_out)
where Q is the heat transfer rate, m_dot_water is the mass flowrate of water, h_water_in is the specific enthalpy of the water entering the cooling tower, and h_water_out is the specific enthalpy of the water leaving the cooling tower.
Given the temperature of the cooling water stream leaving the condenser, you can find the specific enthalpy using the enthalpy-temperature chart for water. Once you have the heat transfer rate, you can calculate the minimum air flowrate using the equation:
Q = m_dot_air * (h_air_out - h_air_in)
where Q is the same heat transfer rate calculated earlier, m_dot_air is the mass flowrate of air, h_air_out is the specific enthalpy of the air leaving the cooling tower, and h_air_in is the specific enthalpy of the air entering the cooling tower.