Study On The Dynamic Characteristics Of Labyrinth Seals

Labyrinth seals has been widely used in turbine machine, so the study on the theory of self-excited and dynamic characteristics has great important theoretical and practical meaning to the designing of a turbine machine with a sound dynamic function. This article is mainly about the study on the dynamic characteristics of Labyrinth Seals and concludes the dynamic characteristic of labyrinth seals with the two-control-volume model by the means of turbulent flow theory and calculating fluid mechanics in order to further study on the flowing law of the labyrinth seals.The main contents are as follows:Firstly, the introduction of the labyrinth seals technology, including the classification the forms and the theory of labyrinth seals.Secondly, this article studies the static working state of the labyrinth seals in steady flow, including the cavity the relative thickness between gear the proportion of cavity depth to cavity width various gears the level angle of gear the influences of helical gear angle and it's flowing direction.Thirdly , this article concludes the main equation set by the means of two-control-volume, and then defines the non-solution variable quality, and finally simplifies the main equation set.Fourthly, this article finds the solution to the main equation set about labyrinth seals model of two-control-volume, concludes the pressure distribution in labyrinth seals, and further obtains the answer of the calculation formula on the four dynamic characteristics about labyrinth seals.Fifthly, this article compares the calculated result to the experimental result andcarries out a comprehensive analysis on the derived formula.Sixthly, this article analyses analyzes the influence of such main factors as the rotor whirling speed, the entrance pre-rotating speed, the entrance pressure and the seals clearance on the dynamic characteristics of labyrinth seals.