EAGER: Ejector Cooling System with Evaporation/Condensation Compact Condenser

EAGER：带有蒸发/冷凝紧凑型冷凝器的喷射冷却系统

• 批准号: 1439296
• 负责人: Hongbin Ma
• 金额: $ 17.5万
• 依托单位: University of Missouri-Columbia
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1439296&HistoricalAwards=false
• 关键词: EAGER; Ejector; Cooling; System; Evaporation

1439296MaCurrently nine out of ten power plants in the United States that generate electricity from steam power require condensate cooling which accounts for approximately 40% of the nation's total freshwater withdrawals and approximately 3% of the nation's total freshwater consumption. In order to significantly reduce or eliminate the use of water for cooling power plants, the proposed research will demonstrate a new generation of ejector-based cooling technology that can result in significant reductions or elimination of the use of water for cooling power plants. Using low-grade thermal energy of steam, an ejector can create a supersonic flow and low pressure zone that can be used to produce cooling. Combining an innovative evaporation/condensation compact condenser, that utilizes hybrid hydrophobic and hydrophilic condensing surfaces and thin film evaporation, an innovative concept of ejector-based cooling technology will be demonstrated. This innovative and potentially transformative system can significantly reduce or eliminate the use of water and significantly reduce the condenser size; furthermore, and it can significantly reduce condensation temperature from 50 °C to 35 °C at an ambient temperature of 30 °C. In addition, this system can be easily integrated into ongoing cooling systems.The proposed cooling system integrates state-of-the-art technologies of ejector refrigeration powered by a low-grade thermal energy, hybrid hydrophobic and hydrophilic condensing surfaces, thin film evaporation, and efficient low-cost oscillating heat pipes. The low-grade thermal energy of steam is utilized to power the ejector refrigeration system. Fundamental understanding of supersonic flow in nozzles, mixing chambers, and diffusers, and its effect on the entrainment in particular, is a missing piece that has restrained ejector refrigeration from wide-spread application. Thermodynamic analysis and fluid dynamic modeling of the supersonic flow will be conducted resulting in a better understanding of ejector performance. A prototype of 5 kW with optimized nozzle, mixing chamber, and diffuser will be demonstrated. The effect of a hybrid hydrophobic and hydrophilic condensing surface on the condensation heat transfer will be conducted in order to provide an insight into fluid flow and condensation mechanisms. Optimization of thin film evaporation can further push the evaporating heat transfer limit to the next level. Low-cost fins embedded with no-wick oscillating heat pipes will be demonstrated to increase the heat transfer efficiency of the air side. The resulting ejector-based compact condenser, if successful, will have significant impact on power plant cooling.

1439296 Ma目前，美国十分之九的蒸汽发电厂需要冷凝水冷却，约占全国淡水总抽取量的40%，约占全国淡水总消耗量的3%。为了显著减少或消除用于冷却电厂的水的使用，拟议的研究将展示新一代基于喷射器的冷却技术，该技术可以显著减少或消除用于冷却电厂的水的使用。利用蒸汽的低品位热能，喷射器可以产生超音速流和低压区，可用于产生冷却。结合创新的蒸发/冷凝紧凑型冷凝器，利用混合疏水和亲水冷凝表面和薄膜蒸发，一个基于喷射器的冷却技术的创新概念将被证明。这一创新且具有潜在变革性的系统可以显著减少或消除水的使用，并显著减小冷凝器尺寸;此外，它可以在30 °C的环境温度下将冷凝温度从50 °C显著降低到35 °C。此外，该系统可以很容易地集成到正在进行的冷却系统中，所提出的冷却系统集成了由低级热能驱动的喷射器制冷、疏水和亲水混合冷凝表面、薄膜蒸发和高效低成本振荡热管的最新技术。 利用蒸汽的低品位热能为喷射式制冷系统提供动力。对喷嘴、混合室和扩散器中的超音速流动，特别是它对卷吸的影响的基本了解，是限制喷射器制冷广泛应用的一个缺失部分。 将进行超音速流的热力学分析和流体动力学建模，从而更好地理解喷射器的性能。一个5千瓦的原型优化喷嘴，混合室，扩散器将被证明。为了深入了解流体流动和冷凝机理，将进行疏水性和亲水性混合冷凝表面对冷凝传热的影响。薄膜蒸发的优化可以进一步将蒸发传热极限提高到一个新的水平。低成本的鳍片嵌入无芯振荡热管将被证明，以提高空气侧的传热效率。由此产生的基于喷射器的紧凑型冷凝器，如果成功的话，将对发电厂冷却产生重大影响。