Question

Determine the heat transfer rate, in
Btu/h,
required to cool a 200. kW electric generator that is
driven by a 300. hp diesel engine. Note: The generator will run cool if it has a zero net energy
transport rate.

Answer 1

Question #79205

Determine the heat transfer rate, in Btu/h, required to cool a 200. kW electric generator that is driven by a 300. hp diesel engine.

Note: The generator will run cool if it has a zero net energy transport rate.

Answer:

The power of the generator in Btu/h is:

$$200 \mathrm{kW} \cdot 3412.14 \mathrm{Btu/h} \cdot \mathrm{kW} = 682,428 \mathrm{Btu/h}.$$

The power of the diesel engine in Btu/h is:

$$300 \mathrm{hp} \cdot 2544.43 \mathrm{Btu/h} \cdot \mathrm{hp} = 763,329 \mathrm{Btu/h}.$$

Thus, to have a zero net energy transport rate we should cool the generator with heat transfer rate of:

$$763,329 \mathrm{Btu/h} - 682,428 \mathrm{Btu/h} = 80,901 \mathrm{Btu/h}.$$