Effect of pore ensemble statistics on load support of mechanical seals with pore-covered faces

A mathematical model was developed for predicting the performance of laser- textured seals with pores. A solution of the two-dimensional steady-state R eynolds equation was given for rectangular and exponential pores, as well a s expressions for the hydrodynamic pressure distribution over the control c ell and for the cell load support. The difference between the two pore shap es can be reduced from a factor of multiple times to 30 percent at most-if the pore volume is kept constant. It was also shown that the total hydrodyn amically induced load-carrying capacity can be obtained with accuracy, ever t if the pore radius of the seal surface is assumed to vary over a wide int erval about its mean value, as it does in reality. Diameters in an ensemble of over 4 . 10(4) pores were run at random for 500 seal faces. It was esta blished for the first time that load support of an ensemble exceeds by 22 p ercent the one determined for N identical pores. The model for the entire p ore population as art ensemble with size variation is more realistic, and s ubstantiates the possibilities and advisability of pore size diversity, hit herto considered undesirable in the pore production process. In general, th e pore ensemble is an essential aspect in exact determination of the load s upport and better insight into the tribologic behavior of pore-covered surf aces.