Research on Face Fluid Field and Seal Performance of T-shape Groove Dry Gas Seal
To obtain more details about the fluid field and high stability of dry gas seal, according to Reynolds equation of compressible perfect gas, on isothermal condition, the controlling equation of gas between the T-shape groove dry gas seal faces is established, and the controlling equation is converted into a non-dimensional equation. The gas flow capacity of T-shape groove dry gas seal is reached with computer simulation in Fluent software, on the basis of numerical simulation, the working parameters (such as, rotating speed, pressure, viscosity of medium, etc.) and the geometric parameters (such as, groove number, groove deep, groove width ratio, balance clearance, etc.) which affect seal performance, are discussed in detail, and the affecting curves are gained. The parameters ( such as, groove deep, balance clearance) which affect seal performance mostly should be chosen correctly in design. The general principle for selecting geometric parameters and working parameters of T-shape groove dry gas seal are obtained, for example, the groove number should be chosen within 12¿16, the groove deep should be chosen within 4¿6 μm, the balance clearance should be chosen within 0.8¿1.4 μm. It offers theoretical support for engineering design and application of T-shape groove dry gas seal.
Gas Seal Performance and Start up Condition Enhancing with Different Seal Groove Geometries
New dry gas seal “DGS” groove geometry has been developed, using a verified three dimensional simulations. The effect of the various groove profiles; standard spiral, tapered-spiral, spiral with an annulus and tapered-spiral with an annulus were studied at wide range of operating speed. The results indicate that, tapered type spiral groove causes a reduction in opening force and in the leakage rate. In addition, increasing the taper angle reduces the temperature distribution inside the gas film and reduces the thermal stresses on the seal mating rings. The combined use of annuals and taper spiral groove decrease the leakage rate for spiral DGS with annular groove only. The final optimized spiral tapered seal with annuals reduces the leakage rate by 18.5% from standard seal, ensures uniform pressure distribution and hydrostatic lift at low speeds, resulting in low torque and reliable operating at start-up condition.
Steady-state and dynamic analysis of a jet engine, gas lubricated shaft seal
Dynamic response of a gas-lubricated, jet-engine main shaft seal was analytically established as a function of collar misalignment and secondary seal friction. Response was obtained by a forward integration-in-time (time-transient) scheme, which traces a time history of seal motions in all its degrees of freedom. Results were summarized in the form of a seal tracking map which indicated regions of acceptable collar misalignments and secondary seal friction. Methodology, results and interpretations are comprehensively described. Presented at the 28th ASLE Annual Meeting in Chicago, Illinois, April 30–May, 3, 1973