Flow Simulations, Inc.
Computational Fluid Dynamics (CFD) Models
Provided on a Consulting Basis for Industry
Contours of liquid volume
fraction inside of a crude
vacuum distillation tower
Eulerian multi-phase model

CFD Heat Transfer

Flow Simulations has modeled over one hundred validations of cfd heat transfer models, primarily in exchangers (or exchanger tubes) to verify the accuracy of results. The validations were comparison of CFD models to empirically obtained results (i.e. field data). This was done because our client was just not interested in CFD Results but in accurately predicting heat transfer coefficients for various design configurations they were building. The main challenge was in getting the outside htc (heat transfer coefficient) predicted correctly over a ranges of flows and flow patterns.

heat transfer in a convection section

heat transfer in a convection section

The picture at right shows flow through a tube bank similar to that of a furnace convection section. Contours of Temperature are shown. This illustration was made to show the discrepancy between often colorful CFD and physical reality. While the simulation appears directionally correct, the CFD calculated htc’s were off by an order of magnitude! Those of you with CFD experience may initially question the turbulence model selected, however, changing the turbulence model is not the panacea you may think it is.

I should also point out that these are not results given to a client. This was a model of cross flow over a tube bank (furnace convection section) that we know is very problematic for cfd and for which empirical validations are available.  In other words we did it because it’s colorful & we knew it’d be wrong.

Prior to starting Flow Simulations, Mr. Krawczyk worked in the heat transfer Department of M.W. Kellogg (now a part of Halliburton) and Bechtel Inc. in Houston, TX.