الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
A seal is a component used in a turbo machine to reduce internal leakage of the working fluid and to increase the machine’s efficiency.
For labyrinth seals, which are widely used, the energy dissipation is achieved by a series of constrictions and cavities. When the fluid flows through the constriction (under each tooth), a part of the pressure head is converted into kinetic energy, which is dissipated through small scale turbulence-viscosity interaction in the cavity that follows.
Therefore, a leakage flow rate prediction equation can be developed by comparing the seal to a series of orifices and cavities. Using this analogy, the mass flow rate is modeled as a function of the flow coefficient under each tooth and the carry over coefficient, which accounts for the turbulent dissipation of kinetic energy in a cavity.
The objective of this project is to develop a simple empirical model for the leakage flow rate in straight through annular labyrinth seals with simple rectangular cavities. The model will allow designers of turbo machines to quickly estimate seal leakage, circumferential velocity distribution, and pressure distribution along the seal at different geometries and operating conditions.
In this work based upon QBASIC program that I designed it to solve the flow rate equation and circumferential velocity distribution equation, the influence of flow parameters and seal geometry on the leakage loss are studies and the relationship between the different geometry elements such as (tooth width, length, and tooth number) and flow rate parameter are plotted against the leakage loss.