## General Mechanical

#### Friction Heat Calculation

• MRMR
Subscriber

Hi

Is there a possibility to create a plot or calculate somehow a heat generated by air friction during a flow in a nozzle?

Regards

• Karthik R

Hello,

Are you talking about viscous dissipation term in the energy equation? This might be important for turbulent and compressible flows. This describes the thermal energy created by viscous shear in the flow. Are you looking to compute this? Which solver do you intend to use - Fluent or CFX? Please let us know here and we might be able to help you here.

Thanks.

Best Regards,

Karthik

• MRMR
Subscriber

I mean the heat produced by air contact with wall during a flow - heat produced by friction. I use Fluent.

• peteroznewman
Subscriber

M.Richert,

Perhaps you need a little grounding in CFD concepts, so that you can receive the help Karthik is offering.

The air in contact with the wall doesn't slide on the wall the way a solid would, that air is fixed. The air next to the air touching the wall slides, air-on-air with friction, and that is what people in the CFD world call viscous shear and that dissipates energy and generates heat.

Regards,
Peter

• MRMR
Subscriber

Thank you Peter. Yes, it's the thing I'm talking about.

• MRMR
Subscriber

Kathrik, so is there a possibility to calculate it somehow in Fluent?

Regards

• peteroznewman
Subscriber

M.Richert,

Karthik already said that it is possible to calculate it in Fluent. I think you are asking how to do it in Fluent.

I have only used Fluent a few times, but I expect it will include the steps of turning on Turbulence and turning on Energy terms.

If you have never built a Fluent model, you can start with just learning how to build simple models. The free edX.org course that has the blue Enroll Now > link at the top of this page has two modules to learn Fluent. A 2D laminar pipe flow, and a 2D turbulent flow around an airfoil. I recommend you do both those modules then search YouTube for examples of air flow with the Energy term on and see what you can learn. When you get stuck, post a specific question, with many screen shots of where you are stuck.

Good luck,
Peter