I am simulating radiator with water as hot fluid and air cooling fluid. water is flowing through tube and air is flowing around tube(like cross heat exchanger). BC Water inlet - mass flow rate and inlet temp- 340 k
Air inlet - velocity and temp-306K
I am expecting approx 4 to 5 degree rise in air outlet temperature
and 6 to 10 degree fall in water temperature.
But I am not getting required result. SOLUTION is diverging.
I am attaching picture of geometry
Increase the air inlet velocity and try.That may help you.
Can you tell more about the numerical modelling. Like what model, scheme and value of Y+ if turbulent case. Also, the value of velocities, and which value is divering? its velocity or temperature
I suppose you are simulating a representative element of an entire radiator. Here are some realistic numbers for you to aim for.
For a 6 to 10 degrees drop in water temperature if you have a 4 to 5 degrees rise in air temperature, it must mean you have an excessive airflow or too small an area. Therefore, increasing air velocity is not the way to go.
For a realistic radiator simulation, take the water inlet temperature as around 368 K (95 C) and return temperature to the jacket as 360 K (87 C). Air temperature rise should be about 20 to 25 C, not more.
Your question is that the solution diverging. I have no answer to that as I never had that problem. However, when you get over that, try for the realistic temperatures I have suggested.
- Badges
- Science topic
- Similar topics
- Engineering
- Thermal Engineering
- Thermofluid
- Heat Transfer