Numerical Analysis of the Vapor Flow in an Axially Rotating Heat Pipe in Drilling Processes
Gustavo Gutierrez and Tien-Chien Jen
Heat pipes offer an effective alternate to conventional methods of removing heat from a drill tip, allowing drilling operations in a dry and environmentally friendly fashion. In this study, a model of the vapor flow in an axially rotating heat pipe is developed. A control volume numerical approach and a staggered grid are used in the development of the computer program. Suction and blowing velocities at the inner wall of the heat pipe are related to a local heat flux input at the evaporator section, and local heat output at the condenser section, respectively. A parametric study is conducted for different rotating speeds and different saturation temperatures of the working liquid of the heat pipe. These parameters significantly affect the hydrodynamics of the vapor flow. It is observed that the vapor flow is strongly influenced by increasing rotating speeds, eventually resulting in flow reversal. It is also found that the saturation temperature has a strong effect on vapor flow velocity distributions. The result of this study will be helpful for further and more complete analysis including the effects of the flow in the liquid film and heat transfer performance of the rotating heat pipe drill.