Author Question: Explain why the temperature change of coolant water in once-through cooling depends on the rate at ... (Read 58 times)

audie · **on:** Jul 28, 2018

Explain why the temperature change of coolant water in once-through cooling depends on the rate at which water is pumped through the condensers.

What will be an ideal response?

Question 2

Alien species usually are aggressive invaders.

What will be an ideal response?

Anton · **Reply #1 on:** Jul 28, 2018

Answer to Question 1

The amount of energy transferred to the water is, by definition of specific heat
(Ch. 7), (water mass) x (specific heat) x (temperature change). Now, a certain amount of
energy is transferred to the water per unit of time. This is the power involved. A pump can
move so much water in a given amount of time (the pump's water transfer rate is measured
in cubic meters per second). The water mass per unit time is the density times the water
transfer rate. Thus, for a fixed power output to the environment, we have
power = (water mass per unit time) x (specific heat) x (temperature change).
The specific heat is fixed. The greater the water transfer rate, the smaller the temperature
change and vice versa.

Answer to Question 2

Some alien species are aggressive, others aren't. It is not possible to know ahead
of time which invaders will exploit their new homes and become nuisances.