Can a Heat Balance be Achieved with Constant Condensation Temperature?

Click For Summary
In a heat exchanger where a fluid condenses at a constant temperature, achieving a heat balance can be challenging due to the temperature difference between the condensing fluid and the cooling fluid. The enthalpy changes during the phase change must be considered, as the heat of vaporization or condensation occurs at a constant temperature. Participants discussed the importance of understanding thermodynamics principles, particularly regarding phase changes and heat transfer. Acknowledgment of these concepts is crucial for solving heat balance equations in such scenarios. Mastery of these thermodynamic principles is essential for effectively analyzing heat exchanger performance.
Kqwert
Messages
160
Reaction score
3

Homework Statement


If you have a heat exchanger with a cooling fluid and a fluid that condenses, and the fluid condenses over the entire heat exchanger i.e. its temperature is constant. How can one make a heat balance in such a case, when dT is 0 for the condensing fluid but not the other? i.e. (m*Cp*Dt)fluid 1 = (m*Cp*Dt)fluid 2

Homework Equations

The Attempt at a Solution

 
Physics news on Phys.org
Kqwert said:

Homework Statement


If you have a heat exchanger with a cooling fluid and a fluid that condenses, and the fluid condenses over the entire heat exchanger i.e. its temperature is constant. How can one make a heat balance in such a case, when dT is 0 for the condensing fluid but not the other? i.e. (m*Cp*Dt)fluid 1 = (m*Cp*Dt)fluid 2

Homework Equations

The Attempt at a Solution

You are aware that enthalpy changes at constant temperature for a phase change of a single component substance, correct? You've heard of the heat of vaporization/condensation, correct?
 
Chestermiller said:
You are aware that enthalpy changes at constant temperature for a phase change of a single component substance, correct? You've heard of the heat of vaporization/condensation, correct?
I wasn't aware that the enthalpy changes at constant temperature for a phase change.
 
Kqwert said:
I wasn't aware that the enthalpy changes at constant temperature for a phase change.
Are you taking thermodynamics now, or have you had it yet?
 
Chestermiller said:
Are you taking thermodynamics now, or have you had it yet?
I haven´t had it yet. We had a small brief on it in the course I am taking, but maybe I didn't pay enough attention.
 
Kqwert said:
I haven´t had it yet. We had a small brief on it in the course I am taking, but maybe I didn't pay enough attention.
Well, I'm sure you know that water boils at a constant temperature of 100C while you are adding heat.
 
Thread 'Correct statement about size of wire to produce larger extension'
The answer is (B) but I don't really understand why. Based on formula of Young Modulus: $$x=\frac{FL}{AE}$$ The second wire made of the same material so it means they have same Young Modulus. Larger extension means larger value of ##x## so to get larger value of ##x## we can increase ##F## and ##L## and decrease ##A## I am not sure whether there is change in ##F## for first and second wire so I will just assume ##F## does not change. It leaves (B) and (C) as possible options so why is (C)...

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
Replies
1
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
5
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 2 ·
Replies
2
Views
6K