A CFD study of flow around an elevator towards potential kinetic energy harvesting

Abstract

The regenerative drive and braking elevator technology capture the kinetic energy from the rope movement based on Faraday's law of electromagnetic induction, thus only applicable to the roped elevator system. The rope-less elevator is anticipated to be future predominant elevator type and can only transfer its kinetic energy via the airflow induced by its car movement, which can be evaluated via aerodynamic studies. However, past aerodynamic studies focus only on the effect of the induced airflow to energy and operational efficiency of the elevator. There are very limited studies on the use of the induced airflow for kinetic energy harvesting. Therefore, this study evaluates the induced flow in terms of air velocity, kinematic pressure, and turbulence, towards the potential kinetic energy harvesting pertaining to the possibility of wind power generation and electricity generation of the rope-less elevator system using CFD based approach through OpenFOAM software. Aerodynamics of the elevator system is simulated using symmetrical quarter three-dimensional elevator model, with parameters of car rated speed and shaft height. The results reveal the potential kinetic energy harvesting from the moving elevator car. Appropriate elevator speed and shaft height should be adjusted accordingly to get the optimum match with the longest time period for the car to run at its rated speed, to generate the most electricity.