Question

A plate and frame heat exchanger has 15 plates made of stainless steel that are 1 m tall. The plates are 1 mm thick and 0.6 m wide and are spaced 4.8 mm apart. The exchanger is used to cool water. The volume flow rate of this water is 0.011 m3/s, and its inlet temperature is 30 C. Raw water is the cooling medium. It enters the exchanger at 6 C with a volume flow rate of 0.02 m3/s. Calculate the outlet temperatures.

Answer 1

14.506°C

Step-by-step explanation:

Given data :

flow rate of water been cooled = 0.011 m^3/s

inlet temp = 30°C + 273 = 303 k

cooling medium temperature = 6°C + 273 = 279 k

flow rate of cooling medium = 0.02 m^3/s

Determine the outlet temperature

we can determine the outlet temperature by applying the relation below

Heat gained by cooling medium = Heat lost by water

= ( Mcp ( To - 6 ) = Mcp ( 30 - To )

since the properties of water and the cooling medium ( water ) is the same

= 0.02 ( To - 6 ) = 0.011 ( 30 - To )

= 1.82 ( To - 6 ) = 30 - To

hence To ( outlet temperature ) = 14.506°C