Ultrasonic suction pump at vapour pressure for condensate return in a vibrating heat pipe

An ultrasonic suction pump for condensate return is characterized and successfully applied to a heat pipe cooled ultrasonic horn operating at 20 kHz. The suction pump is tested at atmospheric and for the first time at heat pipe conditions, i.e. near vapour pressure. Pump characteristic near vapour pressure differs remarkably from that observed under atmospheric conditions. The optimal gap size between pipe and vibrating surface is bigger at vapour pressure and it is less sensitive to gap size adjustments.