With the study of the basic equation in the filtration process ，in order to reduce the workload of the filtration
experiment ，the method was provided using the computer simulation studies on the filtration process ． The cake formation
process was divided into a number of hypothetical increments ．A suitable constant pressure cake filtration simulation program
was designed using the time increments and VB programming language ． Through the program ， a number of relevant
parameters and results can be simulated ．Which propose a reliable new method of the study in cake filtration process ．

The Hilbert-Huang transform（HHT）was applied to analyze the pressure fluctuation signal in submerged circulative impinging stream reactor. The intrinsic mode function（IMF） was extracted from the pressure fluctuation in submerged circulative impinging stream reactor（SCISR）. The non-linear and non-stationary characteristics of the pressure fluctuation signals were demonstrated. Analyzing the energy distribution of high, middle,low frequency segment and its transfer within different IMF, the relationship between the flow regimes identification in SCISR and the energy distribution of the different frequency segment IMF were founded. The results show that the rotate speed gradually rose, the impinging course of particles would caused the vortex with different scales and energy distribution of IMF would caused diversification. Hilbert-Huang transform method exposes internality rule between flow pattern and energy distributing of IMF component that is obtained by decomposing pressure fluctuation signal of SCISR using EMD. At the same time, quantificational proof can be provided.