Design Optimization And Experiment Study On A New Type Of Liquid Pump Driven By Heat

Electricity-driven liquid pumps in heat-driven refrigeration system characterize high power consumption, while those driven by heat with valve-control method are inconvenient in use and less reliable. In this study, a review of heat-driven liquid pump and its application in refrigeration system is firstly introduced. Based on the previously proposed pump driven by high-pressure vapour, the design optimization is conducted and the sample machine is made. CFD method is utilized to analyze the flux characteristics and process segmentation of the low-pressure side. In addition, an experimental setup is built to verify the simulation result and explore the operating characteristics. Main contents and conclusions of this paper is presented as follows:1) A comparison method was proposed to analyze the performance of a pump. The results show that the delivery capability of the proposed pump stands a similar level to the traditional pump powered by Organic Rankine Cycle with low grade heat.2) As revealed in CFD results, mass flux rises approximately linearly at first in full-load condition, then decreases with increasing rotation rate in both round and sector channels. Rotation rate corresponding to the max flux is respectively 85r/min and 180r/min. There exists a smooth section around the max flux, illustrating that there is a stable-operation region of the new pump.3) Compared to round channel, the flux scale of sector channel is wider and the pressure balance performance is better. Using PTFE, glass fiber, carbon fiber and graphite as rotor material is proved to be good in self-sealing, abrasion-resitance and low-friction-coefficent.4) It is proved by experiment that mass flux rises approximately linearly at first in full-load condition, then decreases with increasing rotation rate. Besides, the max mass flux and its corresponding rotation rate decreases with high-pressure increases.5) Input power of assistant electric motor increases approximately linearly with increasing rotation rate at the same high-pressure. The increasing rate and coefficient of delivery performance presents a possitive correlation with high-pressure. Coefficient of delivery performance reaches its optimum value at the end of full-load condition. Sector-channel rotor works more suitable in low rotation rate at higher high-pressure.