The results demonstrate that the heat transfer and pressure loss depend on the helix secondary flow, its mechanisms are due to the working fluid mixing and the development restricting of boundary layers.

The liquid in the annulus between the pumping rod and tubing in the surface-driven progressing cavity pump(PCP) well presents the helical flow under the action of rapidly rotating pumping rod and PCP pressure difference.

In this paper,the kinematic equations of flow of Newtonian fluid of helical flow in eccentric annulus were transformed by the method of undetermined coefficient,the calculation formula of pressure gradient of flow of Newtonian fluid of helical flow in eccentric annulus was obtained.

In this paper, the spiral flows have been studied as research object, the influential factors of the heat transfer coefficient and pressure dro.

The experimental results showed that, the flameout at high load arose not from the changes of re-circulation zone and divergent angle, but from the mismatched primary air and swirl secondary air.

In the present paper, using numerical method mainly and experiment partially, the authors tried to analyze and discuss the generation and the evolution of secondary flow vortices in turbine blade passage.