Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5475698 | Energy | 2017 | 16 Pages |
Abstract
A horizontal two-phase loop thermosiphon (HLTS) has been developed as a potential receiver for parabolic trough collectors (PTCs). The design consists of an evaporator (which is horizontally arranged), a condenser, a riser, and a downcomer with a U-turn. This HLTS was designed to push to higher temperatures than previous HLTS studies (200-400 °C) by using Dowtherm A as the working fluid. An indoor experimental prototype was built to investigate its heat transfer performance. Three regimes: start-up, transition and steady operation were analyzed. A unique feature of this design, the U-turn compensation tube, was shown be helpful during the transition and steady operation regimes since it forms a liquid seal to avoid bidirectional flow in the loop. However, solidification of the working fluid in the U-turn section was found to adversely impact the start-up regime in the case of cold (e.g. frozen) initial conditions. The system was tested up to a heat flux value 11.22 kW/m2. The thermal resistance and the two-phase heat transfer coefficient were demonstrated to be considerably better than prior literature. Moreover, the present HLTS was shown to be theoretically limited to 85.6 kW/m2, thus demonstrating that this type of system can meet the needs of intermediate temperature PTC receivers.
Related Topics
Physical Sciences and Engineering
Energy
Energy (General)
Authors
Yinfeng Wang, Beibei Lu, Haijun Chen, Hongtu Fan, Robert A. Taylor, Yuezhao Zhu,