Experimental Investigation Of Oscillating Heat Pipes

With the miniaturization of electronic components and systems, as well as continuous increase in the power density, the oscillating heat pipe (OHP) plays an important role in the thermal management. The OHP utilizes phase change heat transfer and oscillating motion to transport heat, which is related to complex heat transfer mechanism, surface characteristics, and mechanical system vibration. The OHP can provide an extra high heat transport capability resulting in wide applications. In the current investigation, an experimental system was established and extensive experimental investigations have been conducted including visualization, startup, and steady-state experiments in order to find the primary factors influencing fluid flow and heat transfer in an OHP. The visualization experiment was completed using an infrared camera to measure surface temperature variation of the OHP, which can indirectly find the oscillating motion of liquid plugs and vapor bubbles in an OHP. Results show that the charging ratio, working fluid, heating mode, titled angle, and input power significantly affect the oscillating motion and heat transfer performance. And the start-up of an OHP is dependent on the working fluid. When the power increases, the thermal resistance of the OHP significantly decreases. At a power input of 200W, the OHP can achieve a thermal resistance of 0.1171 K/W for the water OHP investigated herein.