Wenhua Liu^a,b, Mo Yang^c,a,*, Yuwen Zhang^b , Guiliang Liu^a , Liang Ling^a , Xuchen Ying^a,*

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-7, 2023, DOI:10.5098/hmt.20.15

Abstract In this study, numerical investigations are performed on a partially premixed flame of methane and air in two- and three-dimensional models. Nonlinear method is adopted to illustrate the asymmetric phenomenon that affects the flame stability under various co-flow velocities. According to the results, the mathematical relationship between the flame flickering frequency Stanton number and the dimensionless velocity Froude number has been summarized as St=0.7Fr^-0.46. The bifurcation phenomena under different Reynold numbers are found to have significant influence on the system stability. Two critical bifurcation points, which is when Re=300 and Re=1200, are determined as the onset More >

Weiyu Zhang^a , Mo Yang^a,*, Yuwen Zhang^b

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-8, 2019, DOI:10.5098/hmt.12.18

Abstract The periodically fully-developed flow and heat transfer in channels with periodic semi-circular tube is studied numerically by the direct numerical simulation (DNS), the large eddy simulation (LES), and the Reynolds stress model (RSM). When the Reynolds number is between 3000 and 25000, the Nusselt number obtained by the RSM is closer to the experimental results than the results obtained from other turbulence models. The nonlinear characteristics of flow and heat transfer is revealed based on the results of numerical simulation. When Reynolds number is high, the geometric structure and boundary conditions of the channel are More >