Screw Compressors Three Dimensional Computational Fluid Dynamics and Solid Fluid Interaction By A. Kovacevic ,N. Stosic and I. Smith

Screw  Compressors Three Dimensional Computational Fluid Dynamics  and Solid Fluid Interaction By A. Kovacevic  ,N. Stosic and I. Smith 

Contents:

1 Introduction

2 Computational Fluid Dynamics in Screw Machines

3 Grid generation of Screw Machine Geometry

4 Applications.

5 Conclusions

Preface:

Screw compressors are rotary positive displacement machines, which are compact, have few moving parts and which operate at high efficiency over a wide range of speeds and pressure differences. Consequently a substantial proportion of all in dustrial compressors now produced are of this type. There are few published books on the principles of their operation and how best to design them, especially in English. The authors made a first step to fill this void with an earlier work on mathematical modelling and performance calculation of these machines. This described analytical procedures which are generally adequate for most applications, especially when dealing with oil flooded machines, in which temperature changes are relatively small and thus the effect of changes of shape of the key components on performance may be neglected. This assumption permitted the use of analytical procedures based on flow through passages with dimensions that are invariant with temperature and pressure. As manufacturing accuracy increases, clearances can be reduced and compressors thereby made smaller and more efficient. To obtain full advantage of this at the design stage, more accurate procedures are required to determine the internal fluid flow patterns, the pressure and temperature distribution and their effects on the working process. This is especially true for oil free machines, in which temperature changes are much larger and thus make thermal distortion effects more significant. The present volume was prepared, as a sequel to the authors’ earlier work and describes the most up to date results of methods, which are still being developed to meet this need. These are based on the simulation of three-dimensional fluid flow within a screw machine.