Straight-through Labyrinth Seals The Internal Two-dimensional Numerical Simulation Of The Flow Field

Labyrinth seal is one of seal types, widely using in industry.For a long time people constantly research this method and obtain many beneficial fruits.All this fruits are made full use of in manufacture and bring favorable economic benefit.With the fast development of technology, however, every research field of science is up against new challenge.As far as labyrinth seal, though it brought into play in industry, the method connecting with overall seal test reveals limitations.One of them is lake of actual quantitative knowledge of the flow through cavum and clearance of labyrinth.On the basis of the fruits from the grand old men, aiming at the above limitations, this paper makes some research and expects to make a little progress.The object of this research is the effect of geometrical factors on straight type labyrinth seal.The main thought is as the following:Firstly, set up geometrical matrix of straight type labyrinth seal.Then, changing structure sizes (boundary conditions, original conditions etc.) and carrying through respectively numerical valuable calculations, protract flow field and pressure field pictures.Through contrasting and analysis of several critical parameters (the position of volution, the intension of volution, and pressure drop etc.) ensure reasonable geometricaI structures.Finally, compare these resuIts with experimental ones to find out similarities and differences and draw a cone I us ion.In according to the existing industrial structures and making adjustment, choose the geometr ical parameters: space between teeth (s), clearance highness (h), tooth highness (H), tooth width (b).The rangeof the parameters are s/h=10~80, H/s=0.25-1.0, b/h=0.1-20.0.This paper, to some degree, discusses and researches primarily the numerical simulation experiment about the flow field and pressure field of straight type.Integrating what learned, make the following conclusions:The first is to use MATLAB to make program and to simulate the effect of geometrical factors on straight type, which can reveal the flow field and pressure field, to ensure reasonable geometrical structure.This shows, compared with the traditional collective testing method is better.The second is that the reasonable structure of straight type are s/h=40 & 60, H/s=0.5, b/h>10.The third is that obtain flow field pictures under the conditions of numerical simulation through PIV ( Particle Image Velocimetry ).The contrasting shows that the above structure is correct.In a word, this paper calculates rationally the flow field and pressure field in the cavum and clearance of straight type labyrinth, analyses the flow form, offers mathematical matrix and basis for the design of labyrinth.