Laminar free convection in a vertical tube with temperature-dependent viscosity

Abstract

The role of temperature-dependent viscosity was studied in laminar free convection in a vertical tube. This was carried out by applying a finite-difference method to the governing equations of developing flow inside a vertical tube with an isothermal wall. The only parameter necessary to take the temperature dependence of viscosity into account is the ratio of viscosities at the wall and ambient temperatures. An illustrative example is given to show the discrepancy which may arise when a fluid of highly temperature-dependent viscosity such as glycerin is treated as temperature independent.