The purpose of this paper is to obtain the enhanced heat transfer characteristic of the winglet vortex generator (VG) in the helical channel with semicircular cross section. The shape and layout of the VG are concerned. CFD software is adopted to simulate the fluid flow and heat transfer characteristic in the smooth helical channel and that installed with four kinds of winglet vortex generator. The four styles of vortex generator are characterized as jxjs

jxjk

sjjs and sjjk VG

respectively. The simulated data coincide well with the experimental data. The results based on the current research show that after installing the vortex generator

the average ratio of Num to Nu0 is in the range of 1.044—1.074 where Num is the surface average Nusselt number of helical channel within the scope of ±180o away from the vortex generator and Nu0 is the corresponding value of smooth helical channel. However

the specific value between the flow resistance coefficient of helical channel with VG and the corresponding value of smooth channel

i.e. f/f0 is in the range of 1.105—1.188. The rectangular winglet VG is superior to the triangular winglet VG only in terms of heat transfer enhanced. Along with the flow direction

the convergent layout of VG is superior to the divergent layout for heat transferring. Based on the field synergy principle

the secondary flow field structure would be changed by the vortices shedding from the VG. Thus

the cooperativity of flow and temperature fields would be better and the heat transfer would be improved. For the helical channel with rectangular and triangular winglet VG

the compound secondary flow fields are four vortices and two large vortices

respectively

and the length of heat transfer effect is 10.47 and 12.56 times of winglet height

respectively.