TEST 1

What hypothesis of calculation used in the calculation of heat exchangers of concentric tubes? Mark the answers are correct:
1. The temperature is based on the length.
2. Not working in regime stationary.
3. It works with adiabatic conditions
4. The physical properties of fluids are not constant with temperature.
The configurations of heat exchangers can be (check the answers that are correct):
1. Parallel
2. Counter
3. Hot flow
4. Cold flow
The equations of thermal balance (choose the correct answers):
1. Must be proposed for each fluid.
2. You can ask if any of the fluid has a phase change.
3. They are the same as the equations of general step of heat.
4. They referred to the inner or external tube inside.
In the diagrams of distribution of temperature if C1 >C2 (choose de correct answers):
1. The only configuration possible is in parallel.
2. The only configuration possible is in counter.
3. Both parallel and counter, ∆t1< ∆t2
4. Both parallel and counter, ∆t1> ∆t2