Evaluation of turbulence models in the external flow around the heated pipe

   The study of heat exchange processes using numerical modeling in software systems is a complex operation. In the course of conducting numerical studies on heat transfer, it is necessary to adequately adjust the solution of the problem. To do this, the most suitable turbulence models are selected, grid models are created, and boundary conditions are set. Obtaining reliable results of numerical simulation of heat exchange processes directly depends
on setting the correct parameters that need to be analyzed initially, , 4 s  a result of the work on the analysis of the necessary parameters, an adequate solution to the problem can be obtained.

   THE PURPOSE. To evaluate the influence of turbulence models on the heat transfer process and to select the most suitable model for numerical simulation of the external flow around the heated pipe. To study the influence of quantitative criteria of the grid model on the accuracy and convergence of the numerical calculation solution.

   METHODS. During the numerical simulation, the finite element method was used in the ANSYS Fluent software package.

   RESULTS. In the course of the study, the most suitable turbulence model was selected to solve the problem of external flow around the heated pipe. A grid model is constructed taking into account the features of the problem under consideration. The errors are determined depending on the quantitative criteria of the grid model.

   CONCLUSION. Numerical studies have made it possible to give a comparative assessment for pipes with different fins. The results obtained showed that replacing pipes with straight fins with spiral ones allows increasing the heat transfer intensity up to 40 %.

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