平膜蓄能器溶晶过程实验研究

在溴化锂吸收式蓄能系统中,允许溶液结晶会大大提高系统蓄能密度,但是溶液结晶后,放能速率大大降低。为了解决溴化锂溶液浓度差储能器中溶晶困难的问题,本文设计了可以实现快速溶晶的平膜构架蓄能器,搭建了测试膜储能器内部传热传质性能的实验台,并分析了水蒸气流通截面积对传热传质性能的影响。结果表明:所设计的平膜蓄能器可以在60 min内使初始质量分数为65%的溴化锂溶液实现溶晶,此实验方法证实了平膜构架蓄能器的可行性。

Experimental Study on Dissolving Crystals within a Flat Membrane Accumulator

In a lithium bromide absorption-type accumulator system, allowing the solution to crystallize greatly improves the system storage density. However, the crystals seriously affect the discharge process of the energy-storage system. To rapidly dissolve the crystals, a flat-membrane framed accumulator was designed to address this difficulty. The heat-transfer and mass-transfer performance in the accumulator will directly affect the energy-discharge rate of the accumulator. Therefore, a test rig was built to test the heat- and mass-transfer performance in the membrane accumulator. Using experimental data, the heat- and mass-transfer characteristics of the membrane accumulator under different working conditions were analyzed, as well as the influence of the water-vapor cross-sectional area on the heat-and mass-transfer performance. The experimental results show that the crystals in the lithium-bromide solution with an initial mass fraction of 65% can be completely dissolved in 60 min. The feasibility of the flat-membrane framed accumulator is confirmed by this experiment.