Question

A liquid food product is being heated in a well-mixed tank.  The sides of the tank are kept at 77°C.  The tank is 1.69 meters in diameter and is filled with broth to a height of 0.5 meters.  Under the current conditions, the convective heat transfer coefficient is 420 W/m² K.

1. Draw a diagram of the system and label all appropriate parts
2. What kind of heat transfer is occurring from the tank to the broth?  How do you know?
3. How would your answer to part b change if the agitator in the tank was stopped?  Why?
4. Assuming the agitator is turning and the tank is well-mixed for the remainder of the problem, write the heat transfer equation for this system in terms of variables only.
5. If the rate of heat transfer from the tank to the broth is 30 kW, what is the bulk temperature of the broth?
6. Assuming you couldn’t change the physical properties of the broth or tank, describe two ways to increase the convective heat transfer coefficient.

Answer 1