|
Compared with other types of seal, dry gas seal has the merits of high reliability, long lifetime, no pollution and economical characteristic, so it is more widely used in petroleum, natural gas, chemical and aircraft industries.At first, the present researching status of gas seal and the subsistent problems are summarized, the developing trend is pointed out, and the working principle of dry gas seal is introduced in this paper.On the basis of basic principle of hydro-mechanics, the flow model of the gas between the T-groove dry gas seal faces is established. The non-dimension controlling equation is gained by predigesting, and some formulae of the primary parameters, such as, film pressure, film thickness and leakage, etc, are established. The controlling equation can gain a solution by numerical value method, such as, finite element method. In the same time, the advantage of finite element method is introduced.From the point of computing hydro-mechanics view, the three-dimensional geometry model of the T-groove dry gas seal is built in SolidWorks software, and the model is accorded with the actual physical significance. The girding of the computing region is reached with Gambit software. The gas flow capacity of T-groove dry gas seal is reached with computer simulation in Fluent software. The feasibility of this method is proved by the result of spiral groove dry gas seal, and the distribution law of T-groove dry gas seal liquid pressure field is gained.A calculation of the balance face clearance of T-shape groove dry gas seal is proposed as follows, Through using numerical simulation method to calculate the opening force, and combining the evaluation of the closing force to determine the balance face clearance of T-shape groove dry gas seal, which provides a basis judgment for seal running state.On the basis of number of numerical simulation, the working parameters ( such as, speed, pressure, etc. ) and the geometry parameters (such as, groove number, groove deep, groove-ridge width radio, seal dam and groove radio, etc.) which affect seal performance, were discussed in detail, and the affecting curves are gained.By studying the T-shape groove dry gas seal performance and balance face clearance, some universal law is gotten. This paper offers theoretical support for engineering design and application of the T-shape groove dry gas seal, and lays a solid foundation to the seal parameters optimized, stability analysis, dynamic analysis, deformation and heat distortion, and other research followed-up.
|