Experimental investigations of flat T-shaped copper and titanium heat pipes

Abstract

• Two flat copper–water and titanium-acetonitrile heat pipes were experimentally investigated. • The flat heat pipes have the novel T-shaped design, which provide the heat transfer between perpendicular surfaces. • Acetonitrile was used as a working fluid for the titanium heat pipes. Two flat T-shaped 1) copper–water and 2) titanium-acetonitrile heat pipes were experimentally investigated. The novel T-shaped design of the heat pipes provides efficient heat transfer between perpendicular surfaces. The maximum heat transfer rate of the flat copper–water heat pipe is 75 W at a temperature of 67 °C. The maximum heat flux for heat sources with the area of 2 cm 2 is 10 W/cm 2 at a distance of 100 mm from the heat removal area. Such flat T-shaped copper–water heat pipes are currently used in standard equipment to remove heat from electronic components. The flat T-shaped titanium heat pipe has a similar design. Acetonitrile was used as a working fluid for the titanium heat pipes because of its restricted outgassing, ability to work in sub-zero temperatures and relatively low pressure of saturated vapor compared to other conventional working fluids (acetone, methanol). The titanium-acetonitrile heat pipe provides heat transfer for heat loads 2–3 times lower than the copper–water heat pipe, but the weight of the titanium heat pipe is much smaller, which is important for space applications.