| The objective of this research is to develop guidelines for the design of direct-acting, differential area relief valves by understanding the effects changes in geometry of the internal components has on valve performance.; This was accomplished using a three-pronged approach: by simulating the relief valve using a computational fluid dynamics code, by experimental testing of actual component geometries, and by visualization of the flow in a scale model of the relief valve.; The numerical simulation of the relief valve proved to be in reasonable agreement with the flow visualization and experimental results, while these results were qualitative rather than quantitative. Simulation of the flow field for the steady state and the transient solution were in agreement with the model predicting the influence of the seat angle, exhaust hole diameter, and hole position on valve performance.; The experimental investigation revealed how a number of component geometry variations influenced valve performance; this research will be useful to designers by providing guidelines that will assist in reducing production time, manufacturing costs, as well as reducing the number of components needed to produce the particular operating pressure ranges.; In a more fundamental sense the results of this research effort will provide valve designers with an improved understanding of the flow inside a direct acting valve as well as with valuable information on the influence of valve geometry and components on valve performance.*; *This dissertation includes a CD that is compound (contains both a paper copy and a CD as part of the dissertation). The CD requires the following applications: Adobe Acrobat, QuickTime Movie Player. |
