An Aerodynamic Mathematical Model for Super-High-Speed Elevators

As the cities are becoming more and more densely populated, buildings are getting higher and higher. The proposal of ‘kilometer-high building’ has already been announced and therefore, the demand for super-high-speed elevators is highly increasing. The rated speed record of 600 m/min was achieved in 1977 and then 750 m/min in 1993. Now, elevators up to 840 m/min are being developed. The existing mechanical problems associated with the development of high speed elevators are associated with noise and vibration. For high speed elevators, aerodynamic noise is usually lager. Hence, it is essential to understand the air flow patterns around a super-high-speed elevator car. In this paper, a simplified mathematical model has been developed based on computational fluid dynamics (CFD) to study the fluid flow patterns above a travelling car. This model, though very much different from the real situation, is the beginning point of a comprehensive model. It can be used to simulate some interesting phenomena inside the hoistway. The ultimate goal is to make use of CFD models as computer assisted tool to design a new car frame such that the problems of noise and vibration can be solved under super-high-speed operation. It must be noted that the models are used for designing external car frame and hence high accuracy from CFD point of view it is not the most critical issue to be considered.