Abstract
Modelling of the passive scalar flux is considered. An algebraic relation for the scalar flux in terms of mean flow quantities may be formed by applying some equilibrium condition on the transport equations for the scalar flux. This modelling approach is analogous to explicit algebraic Reynolds stress modelling (EARSM) for the Reynolds stress anisotropies. The resulting set of algebraic equations are implicit and non-linear even with linear modelling of the pressure-scalar gradient correlation. A method to solve this implicit relation in a fully explicit form is proposed where the non-linearity in the scalar production to dissipation ratio has been considered and solved. This method is analogous to that used in the EARSM by Wallin et al. [5]. The solution is exact in two-dimensional mean flows. In three-dimensional mean flows the tensorial form is exact but an approximation for the scalar production to dissipation ratio is introduced. For a special choice of two of the model parameters a drastically simplified model results. This also gives a simple formulation even for three-dimensional mean flows. Comparisons are made with DNS data of a turbulent channel flow, with a passive scalar, by Wikstrom et al. [7].
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
