Rotary regenerator design optimisation and heating surface selection

[摘要] ENGLISH ABSTRACT:The rotary regenerator is far from a new device and since its invention more than 70 years ago it has developed into a carefully engineered product. They are mainly used for gas to gas heat transfer and find application in electricity generating plants and in refrigeration and air conditioning systems amongstothers. Today the challenge in regenerator design is the optimisation of the operating conditions and the development of improved heating surfaces. The objective of this study is to make a contribution in this respect. The design theory for regenerators is investigated and the dimensionless parameters onwhich the regenerator effectiveness depends are identified. Approximate solution methods for regenerators are evaluated by comparing their accuracy to more accurate numerical results. The best approximate solutions obtained from the accuracy analysis are used to formulate a regenerator design method.A computer program is written to thermally evaluate or design a rotary regenerator. The program uses either the approximate theory or more accurate numerical methods, depending on user specification. The program can be used to optimise some of the operating conditions.Several new heating surfaces are experimentally tested for their heat transfer and pressure drop characteristics. The performance of the heating surfaces is compared to each other in a specific regenerator application. A cost effectiveness parameter is defined for comparison purposes. It is shown by anexample how the matrix rotational speed, the flow split ratio, the matrix wall thickness can be optimised.

[发布机构] Stellenbosch University