Potential flow analysis of the transition from an external flow to an internal flow of a receiver/diffuser

Author

Mark W. Wendel

Date of Award

12-1985

Degree Type

Thesis

Degree Name

Master of Science

Major

Mechanical Engineering

Major Professor

Gary V. Smith

Committee Members

Rao V. Arimilli, James A. Euler

Abstract

A two-dimensional computational potential flow model has been developed to describe the flow field characteristics of a submerged jet impinging on a receiver/diffuser. This model is a first effort at understanding the transition from the external jet flow to the flow internal to the receiver/diffuser.

The flow field is divided into one upper flow region and one lower flow region which interact across a free-surface boundary. Since the orientation of the free surface dividing these two regions is not known initially, an iterative scheme is used to solve the flow field. As the dividing free surface orientation and associated r boundary conditions are changed through iteration, a Cauchy Boundary Integral method is used to solve both flow regions.

The method is verified with the exact solution of flow around a cylinder by shaping a receiver/diffuser to a cylindrical shape with a trailing "tail" section. The receiver/diffuser problem is solved using diffuser half angles of one, three, and five degrees. Comparisons of flow rates and wall pressure distributions are made with published results. Additionally a two-dimensional pressure distribution within the receiver/diffuser is plotted.

It was discovered that the model differed from the receiver/diffuser problem by predicting "induced" velocity-magnitudes in the surrounding fluid as large as the jet velocity, although this large amount of flow did not pass through the receiver/diffuser. However, the pressure distribution trend along the inside of the receiver/diffuser wall matches the trend in the experimental results. It is expected that the model would be useful in analyzing critical internal aspects of the receiver/diffuser design.

The recommendation is made to continue the analysis by changing the boundary conditions on the upper flow region and fixing the receiver/diffuser back pressure as the independent variable.

Recommended Citation

Wendel, Mark W., "Potential flow analysis of the transition from an external flow to an internal flow of a receiver/diffuser. " Master's Thesis, University of Tennessee, 1985.
https://trace.tennessee.edu/utk_gradthes/14463