Considering fluid temperature-dependent viscosity

turbulent flow and heat transfer in the jackets with helical ducts were investigated numerically. Comparisons between experimental values and simulated values indicated that the simulation method was reliable. Based on the simulated results

the effects of temperature-dependent viscosity on the characteristics of turbulent flow and heat transfer were studied

variations of the mean flow resistance (fRem) and mean Nusselt number (Num) of cross section in the flow direction were analyzed

and the whole flow resistance and the whole Nusselt number of varied viscosity flow were compared with those of constant viscosity flow. The results show that temperature-dependent viscosity affects the features of fluid flow and heat transfer in the jackets to a certain extent. The development of fRem and Num along the axial direction is divided into the early

the middle and the later stages. The difference is obvious at the later developing stage between the trends with varied viscosity and constant viscosity. Under the same incoming flow and thermal boundary conditions

compared to those with constant viscosity

the local flow resistance with varied viscosity is lower

the local Nusselt number is larger

so that the whole flow resistance is lower and the whole Nusselt number is larger. Furthermore

with the decrease of the Reynolds number and the dimensionless curvature ratio

differences between the characteristics of flow and heat transfer for varied and constant viscosities are more obvious

so temperature-dependent viscosity is a greater contributing factor to fluid flow and heat transfer.