Page History

...

Step 1: Pre-Analysis & Start-Up

With the current problem setup, we know that the temperature will increase as the air passing through the heated section. Depending on whether the pipe is long enough, we might see uniform temperature at the end of the pipe.

Since the pipe cross-section is circular and heat is applied in an axisymmetric manner, we'll assume that the flow is axisymmetric. In cylindrical polar coordinates, this means that the flow variables depend only on the axial coordinate x and radial coordinate r, and are independent of the azimuthal coordinate θ. Hence we can model the pipe problem with a rectangular domain.

Figure above shows the simplified geometry of our problem where Here R = radius of the pipe, and L = length of the pipe. Rotating the above rectangle 360 degrees about the axis will recover the full pipe geometry.

Start ANSYS

...

FLUENT

We are using FLUENT in solving this problem. With the new release of ANSYS 12, there have been a lot of improvement in term of overall flow. We start our simulation by first starting the ANSYS workbench.'ll run FLUENT within the ANSYS Workbench interface. Start ANSYS workbench:

Start > All Programs > ANSYS 12.0 > Workbench

...

• We start by preparing our geometry
• We use geometry to generate a mesh
• We setup the physics of the problem
• We run the problem in the solver to generate a solution
• Finally, we post process the solution to gain insight into the results

Note to Cornell students enrolled in MAE 4272, Fall 2009: You can skip the geometry and meshstepsmesh steps. Download the mesh by right-clicking here and saving the zip file to a convenient location. Unzip the file. This will create a file called pipe.wbpj and a folder called pipe_files. read in the mesh into Workbench using File > Open. Then skip to Step 4: Setup (Physics).

...