Prediction of Two-Phase Heat Transfer and Pressure Drop in Dilute Gas–Solid Flows: A Numerical Investigation

In this article, numerical simulations are performed using a Euler-Euler approach for the gas–solid flows in a horizontal pipe accounting for four-way coupling. The computational domain is a 55-mm-diameter pipe with a length-to-diameter ratio of 100. The effects of two important flow parameters, gas Reynolds number (in the range 37,640–94,100) and particulate loading (in the range 1–20), on the overall pressure drop and heat transfer are investigated. It is observed that the addition of solid particles (spherical fly ash particles of size 30–50 µm) to the gas flow resulted in an increase in pressure drop as well as heat transfer in comparison to single-phase flow. A simplified correlation is also developed for two-phase Nusselt number using nonlinear regression analysis in a non-dimensional form.