Aheat exchanger is to heat water (cp = 4.18 kj/kg·°c) from 25 to 60°c at a rate of 0.2 kg/s. the heating is to be accomplished by geothermal water (cp = 4.31 kj/kg·°c) available at 140°c at a mass flow rate of 0.3 kg/s. determine the rate of heat transfer in the heat exchanger and the exit temperature of geothermal water.

The heat exchanger is 29.26 kJ/s.

The exit temperature of geothermal water is 117.37°C.

Explanation:

Given that,

Specific heat

Initial temperature = 25°C

Final temperature = 60°C

Specific heat by geothermal

Temperature = 140°C

Mass flow rate = 0.3 kg/s

We need to calculate the rate of heat transfer in heat exchange

Using formula of  rate of heat transfer in heat exchanger

Put the value into the formula

We need to calculate the exit temperature of geothermal water

Heat transferred to feed water= Heat transferred by geothermal water

Hence, The rate of heat exchanger is 29.26 kJ/s.

The exit temperature of geothermal water is 117.37°C.

thermal energy is the answer

the answer is false. this is because for ice to melt, it requires latent heat of melting. latent heat means heat energy required to change phase without any increase in temperatures. therefore, the ice will take energy from the environment to melt hence atmospheric temperatures will reduce.