Modification of SIMPLE algorithm to handle natural convection flows with zero-isothermal compressibility. (March 2017)

• Record Type: Journal Article
• Authors: Asako, Yutaka; Faghri, Mohammad
• Is Part Of: International journal of heat and mass transfer. Volume 106(2017:Mar.)
• Page Start: 177
• Page End: 182
• Publication Date: 2017-03
• Subjects: SIMPLE -- Non-Boussinesq approximation -- Isothermal compressibility; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2016.10.052
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Convergence problem of SIMPLE algorithm was investigated for unsteady natural convection in a cavity. SIMPLE algorithm encounters the convergence problem when the fluid has zero-isothermal compressibility. The cause of convergence problem was found and modification of SIMPLE algorithm was proposed. Physically consistent results were obtained by using modified SIMPLE algorithm. Residual of the continuity equation is an appropriate indicator of convergence in the SIMPLE algorithm. Abstract: The conventional SIMPLE algorithm for the pressure–velocity coupling has been adopted by many commercial and non-commercial CFD codes. It encounters convergence problem when it is used to solve unsteady natural convection flows with zero-isothermal compressibility. In this paper, a modified version of this algorithm is proposed to remedy this drawback. The modification includes updating of the density at each time step based on its value at the previous time step to satisfy the continuity equation. As an example of utilizing the modified SIMPLE algorithm, the unsteady natural convection in a rectangular cavity with isothermal vertical walls and adiabatic horizontal walls was computed. Physically consistent results were obtained.