A General Approach for Predicting Convective Heat Transfer Coefficients in Turbulent Systems using Large Eddy Simulations

A generalized approach for predicting turbulent convective heat transfer coefficients using large eddy simulation is presented. This model is based on semi-empirical transport theory, which links the local convective heat transfer rate to the local energy dissipation rate within the near-wall boundary layer.  We apply these approaches to agitated tanks, pipe flow systems, cylinders in crossflow, and tube bundles. We validate the generality and reliability of the theoretical model against expectations from experimentally derived empirical design correlations.

We assess the generality of this approach by considering various industrial systems, including agitated vessels, pipe flow systems, cylinders in crossflow, and tube bundle systems. We assess its correctness by comparing predictions for each system at multiple operating conditions to expectations from experimentally parameterized design correlations. We demonstrate that this first-principles approach can consistently predict heat transfer rates with an accuracy comparable to the empirical correlations. Although attention must be given to simulation resolution, the procedure requires no parameter tuning or adjustment between system topology, operating conditions, or scale. The agreement between theory and experiment is noteworthy, considering the simplicity of the implementation and the simulation calculation speed.

The findings from this investigation present three key implications: first, as a complement to physical testing, this modeling approach can be used to reliably predict local and overall heat transfer rates in silico using first-principles simulations. Second, because the approach directly appeals to the Navier-Stokes equations, it provides mechanistic insight into the link between operating conditions, fluid flow, and convection. Third, because heat transfer is modeled in tandem and on-the-fly with the underlying fluid dynamics, the combined effects of convection and advection can be investigated directly. In this sense, the approach can be used to perform first-principles multi-physics simulations that make a priori predictions of convective heat transfer rates and thermal transport through turbulent flows.