From the graph shows the relationship between the heat pipe thermosyphon inclination angle of bessieres case adjust evaporating condenser sections, and 0 60 90o Pipe length 300 mm.The working fluid temperature R-134a evaporator 80 oC. When the tube comparison. It was found that with the pipe thermosyphon case tilt angle evaporator and condenser sections 90o heat transfer rate per unit area got the most.0 60o