In this paper, characteristics of flow and convective heat transfer of China RP-3 kerosene in straight circular pipe were numerically studied. Navier-Stokes equations were solved using RNG k- turbulence model with low Reynolds number correction. The thermophysical and transport properties of the China RP-3 kerosene were calculated with a 10-species surrogate and the extended corresponding state method (ECS) combined with Benedict-Webb-Rubin equation. The independence of grids was first studied and the numerical results were then compared with experimental data for validation. Under flow conditions given in the paper, the results show that deterioration of convective heat transfer occurs when the wall temperature is slightly higher than the pseudo-critical temperature of kerosene for cases with wall heat flux of 1.2 and 0.8 MW/m 2 . The degree of the heat transfer deterioration is weakened as the heat flux decreases. The deterioration, however, does not happen when the heat flux on the pipe wall is reduced to 0.5 MW/m 2 . Based on the analysis of the near-wall turbulent properties, it is found that the heat transfer deterioration and then the enhancement are attributed partly to the change in the turbulent kinetic energy in the vicinity of pipe wall. The conventional heat transfer relations such as Sieder-Tate and Gnielinski formulas can be used for the estimation of kerosene heat convection under subcritical conditions, but they are not capable of predicting the phenomenon of heat transfer deterioration. The modified Bae-Kim formula can describe the heat transfer deterioration. In addition, the frictional drag would increase dramatically when the fuel transforms to the supercritical state. aviation kerosene, supercritical, convective heat transfer, numerical study Citation:Dang G X, Zhong F Q, Chen L H, et al. Numerical investigation on flow and convective heat transfer of aviation kerosene at supercritical conditions.
a b s t r a c tTurbulent flow and convective heat transfer of supercritical kerosene flow in an axisymmetrically heated circular tube with a diameter of 2 mm and at a mass flow rate range of 0.0015-0.015 kg/s and a wall heat flux range of 0.15-2.0 MW/m 2 are numerically studied using Reynolds averaged Navier-Stokes method with a two-layer turbulence model. The thermophysical and transport properties of kerosene are determined by a 10-species surrogate with the Extended Corresponding State method. Mesh dependency is first investigated and numerical results of fuel and wall temperatures are compared with experimental data for validations. The results show that flow properties such as velocity and Reynolds number increase significantly along the axial direction as the fuel temperature rises and kerosene undergoes the state transition from liquid to supercritical state. Deterioration of convective heat transfer is found to occur when the wall heat flux exceeds a critical value and at the same time, the wall temperature approaches the pseudo-critical temperature of kerosene. The present results show that deterioration of heat transfer are attributed to the development of turbulent properties in the near-wall region based on the results of turbulent kinetic energy and turbulence production term. The relation between the critical heat flux (q wc ) for occurrence of heat transfer deterioration and the mass flux (G) is studied and a fitting formula of q wc and G is obtained.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.