Compressor Volute Design System: Part II — New Volute Design System Approach

Volutes are widely used in industrial process, refrigeration system, small gas turbines and gas pipeline centrifugal compressors as the transition from the impeller-diffuser to the pipings, because of their simple structure, ease of production and wide operating range. This paper illustrates a new design tool that incorporates a new volute design system that integrates and automates geometry generation, grid generation and aerodynamic analysis. In optimizing the available technology in terms of grid generation, CFD, and computer graphics, the program will utilize existing technology used by industry to generate a powerful volute design tool. The design tool is programmed in a way that integrates the features and methods a designer would use for volute design. This is fundamentally by means of geometrical constraints and/or functional relationships. Grids can be generated in minutes accommodating geometrical changes thus reducing the bottlenecks associated with geometry/grid generation for CFD applications. Prior to most CFD analysis work, a structured grid must be produced ensuring high quality such that convergence is assured and the time to convergence of the solution is minimized. However, there are usually only a few people that have the required skills to produce the geometry and generate a high quality structured grid. In essence, the tool provides a sidestep around both the geometry generation and the grid generation process. It automates the process such that anybody can produce a high quality grid from the geometry and move straight to the CFD component of the work and hence can incorporate CFD as part of the design process. The volute design tool will enable the user to generate a family of volutes and display 2D volute cross sections and 3D solid models of the scroll, diffuser inlet, discharge conic, and connecting channel. Separate interfaces will be written to accommodate the different operating systems. The geometry generation will be written in windows however, a separate interface will be written to produce the grid being compatible in NT, Unix, and Linux platforms.