摘要: |
搭建了带有新型分水器的储热水箱分层特性测试的实验台,测试并绘制了在水箱初始温度50 ℃,进水温度20 ℃,流量1.18 L/min、3.19 L/min、5.20 L/min时,水箱各层温度随时间变化的曲线。结果显示,流量越大,温度曲线突变段的斜率越大,分层破坏越明显。并在热力学第一定律、热力学第二定律的基础上,用体积、能量分析和?分析的评价指标对水箱的分层特性进行了研究,结果显示,在流量为1.18 L/min、3.19 L/min、5.20 L/min时的取出效率分别为93.7%、95.7%、96.7%,用能效率分别为98.2%、95.7%、92.3%,三组流量都具有较高的取出效率和用能效率,无量纲时间为0.7时,无量纲?分别为13.3%、14.6%、17.6%,大流量相较于小流量分层效果更差。 |
关键词: 太阳能 分层 储热水箱 分水器 用能效率 无量纲㶲 |
DOI: |
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基金项目: |
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Experimental Analysis of the Stratification Characteristics of a Water Storage Tank with New Stratifier |
Wang Chongyuan,Zhang Hua,Wang Zilong |
(Institute of Refrigeration and cryogenics, University of Shanghai for Science and Technology) |
Abstract: |
Test rig is established to measure the stratification characteristics of a water storage tank with new stratifier. When the initial temperature of the tank is 50℃ and the inlet temperature of the water is 20 ℃, the temperature of each layer in the tank is measured when the flow rate is 1.18 L/min,3.19 L/min,5.20 L/min respectively,. The results show that, when the larger the flow rate is, the larger is the slope of the sudden change in temperature curves, the destruction of stratification is more obvious. Based on the first law of thermodynamics and the second law of thermodynamics, the methods of volume, energy and exergy are used to describe the stratification characteristics of the tank. The results show that, when the flow rate is1.18 L/min,3.19 L/min,5.20 L/min respectively, the extraction efficiency is 93.7%, 95.7%, 96.7% respectively; the discharge efficiency is 98.2%, 95.7%, 92.3% respectively, which indicate that high extraction efficiency and discharge efficiency is got in three flow rates; when the dimensionless time is 0.7, the exergy efficiency is 13.3%, 14.6%, 17.6% respectively, and the stratification is worse for high flow rate than that with low flow rate. |
Key words: solar energy stratification storage tank stratifier discharge efficiency dimensionless exergy |