After reading through the Introduction to GUMBO and the Frequently Asked Questions, the objective of this tutorial is to familiarize the user on the use of GUMBO, the boundary condition, connectivity, and general grid manipulator software of MSU TURBO.
This tutorial is an aide to familiarize the user with the steps to prepare a problem for MSU_TURBO:
Read in the case s37_ts (APNASA data) which should be bundled with MSU_TURBO. The file can be read through the Read Data Panel.
| Once the grid has been read, the user should orient themselves on how to manipulate the graphical image and to be able to select the blocks, faces, edges, etc. |
| Verify the Boundary Conditions. The advantage of using APNASA data is that all boundary information is predescribed; however, the leading & trailing edge and the hub & tip clearance information should be verified. Display the no_slip boundary conditions of the s37_ts case. The figure to the left should the various solids with differenct colors. The hub no slip surfaces are depicted in yellow, the shroud is cyan, the blades of the first blade row are green and the blades for the second are orange. The no slip boundary conditions have been automatically put into groups. |
Calculate the Load Balance Efficiency. This current value should be 0.843246. It is desired to have a value as close to 1.0 to be highly effective; however, the consideration of memory balancing especially with the time shift approximation should probably be the highest concern.
| In this case, divide both blocks in the I and J directions in half. Enter "/2" in the at Index field in the Manipulation Panel and use Split. There now should be eight blocks and the load balance efficiency is 0.835311. The blocks should be renumbered sequentially from 1. Note, the turbo solver expects the blocks are consecutively numbered within blade passages first then across blade rows. The boundary condition, connectivity, and grid files will then be synchronized. This is a necessary step, since GUMBO will not save the data until after validation of this operation. |
| Check the faces to ensure that boundary conditions and connectivities exist and do not overlap. The boundary conditions can be checked again. There should be no problems indicated. This is due to the fact that GUMBO automatically created the block connectivity upon splitting. |
At this point the grid and q data are ready to be saved as input for the solver.