1st Law of Thermodynamics: Steady-Flow Devices

Question 1

If density is constant across the control surface, what is the mass flow rate?

Answer 1

Mass flow rate = Density * Average Velocity * Area

Question 2

What is the difference between a Steady Flow Process and an Unsteady Process?

Answer 2

Steady-Flow doesn’t change with respect to time, whereas Unsteady is time-dependent

Question 3

What does a nozzle do?

Answer 3

It increases the velocity of the fluid by decreasing the area the fluid can travel through

Question 4

What does a diffuser do?

Answer 4

Decreases the velocity of the fluid by increasing the area that the fluid can flow through

Question 5

What does a turbine do?

Answer 5

Extracts useful work from the fluid as high energy fluid flows in and work is extracted through the turbine

Question 6

What does a compressor do?

Answer 6

Increases the energy of the fluid due to the work done on the shaft

Question 7

What does a throttling valve do?

Answer 7

Causes a large drop in pressure, which may be accompanied by a large temperature drop

Question 8

What types of throttling valves are there?

Answer 8

• An adjustable valve
• A porous plug
• A capillary tube

Question 9

What does a mixing chamber do?

Answer 9

Mix two or more streams of fluid

Question 10

What does a heat exchanger do?

Answer 10

Causes the heating and cooling of fluids without mixing