EPRI: Collaborative Research: autoFlutter: Efficient, Waterless Power Plant Cooling

EPRI：合作研究：autoFlutter：高效、无水发电厂冷却

• 批准号: 1357813
• 负责人: Ari Glezer
• 金额: $ 39.86万
• 依托单位: Georgia Tech Research Corporation
• 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: 2014-05-15 至 2018-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1357813&HistoricalAwards=false
• 关键词: EPRI; Collaborative; Research; autoFlutter; Efficient

1357813GlezerThe rate of consumption and withdrawal of water for use in power plant cooling systems has become untenable in light of limited water supply and cost, as well as regulatory restrictions, and environmental concerns. However, the effectiveness of dry air cooling of current, conventional condenser systems has been hindered by the high thermal resistance and poor air thermal capacity of the cooling air. It is clear that in order to enable an appreciable decrease in water consumption for power generation, the heat transfer between the condensing steam and the air-side medium must be significantly enhanced. Earlier attempts to improve the air-side heat transfer focused on the addition of surface features (dimples, etc.) on the cooling fins with limited success and significant increase in fan power. The proposed program overcomes the limits of air-side heat transport by exploiting interactions between the cooling air flow and miniature, autonomously-fluttering reeds (AFRs) to induce the formation and advection of small-scale vortical motions near the condenser fin surfaces. A unique aspect of this approach is that reed flutter is generated by harnessing mechanical energy from the embedding cooling air flow at exceedingly low penalty in pressure losses. These low-cost thin reeds can be tailored for different regions of the condenser and fabricated either integral to the external condenser surfaces or as drop in retrofit assemblies for existing condensers. The reed assemblies are easy to install and maintain without plant level infrastructure modifications. Preliminary heat transfer enhancement and pressure drop analyses coupled with condenser designs and power plant simulations have shown that air-cooled condensers using AFR technology can increase plant efficiency while significantly reducing water consumption compared to wet cooling. The research program will focus on enabling advances in thermoelectric power plant condenser technology to overcome current limits of cooling by dry air and thereby significantly reduce water usage for evaporative cooling. The present approach overcomes the limits of air-side heat transport by exploiting interactions between the cooling air flow and miniature, autonomously-fluttering reeds (AFRs) to induce the formation and advection of small-scale vortical motions near the condenser fins. A unique aspect of this approach is that reed flutter is generated by harnessing mechanical energy from the embedding cooling air flow at exceedingly low penalty in pressure losses. The program encompasses integrated experimental/modeling/numerical investigations that will focus on the fundamental knowledge needed to implement, design, and optimize the use of the AFRs, and demonstrate their efficacy in improving the heat transfer characteristics of finned air-side passages of condensers in power plant configurations and operating conditions. The research at Georgia Tech will focus on experimental investigations of the heat transfer characteristics enhanced by the AFRs along with the modeling, design, and testing of novel condenser configurations enabled by the AFR technology. Johns Hopkins University will focus on CFD investigations of small-scale heat transfer and performance evaluation and optimization of AFR-enhanced condenser configurations. Small-scale heat transfer enhancement by AFRs was recently demonstrated in air-cooled heated ducts at Georgia Tech with significant heat transfer enhancement. These low-cost thin reeds can be tailored for different regions of the condenser and fabricated either integral to the external condenser surfaces or as drop in retrofit assemblies for existing condensers. The reed assemblies are easy to install and maintain without plant level infrastructure modifications.

1357813Glezer 鉴于有限的供水和成本以及监管限制和环境问题，发电厂冷却系统的用水量和取水率已变得难以维持。 然而，当前传统冷凝器系统的干空气冷却的有效性受到冷却空气的高热阻和较差的空气热容量的阻碍。 显然，为了使发电用水量明显减少，必须显着增强冷凝蒸汽与空气侧介质之间的传热。 早期改善空气侧传热的尝试集中于在散热片上添加表面特征（凹坑等），但成功有限，但风扇功率显着增加。 所提出的方案通过利用冷却气流和微型自主颤动簧片（AFR）之间的相互作用来诱导冷凝器翅片表面附近小规模涡旋运动的形成和平流，从而克服了空气侧热传输的限制。 这种方法的一个独特之处在于，簧片颤动是通过利用嵌入冷却气流的机械能来产生的，压力损失的损失极低。 这些低成本的薄簧片可以针对冷凝器的不同区域进行定制，并且可以集成到外部冷凝器表面，也可以作为现有冷凝器的嵌入式改造组件。簧片组件易于安装和维护，无需修改工厂级基础设施。 初步的传热增强和压降分析以及冷凝器设计和发电厂模拟表明，与湿式冷却相比，使用 AFR 技术的风冷冷凝器可以提高工厂效率，同时显着减少水消耗。 该研究计划将重点关注热电厂冷凝器技术的进步，以克服目前干燥空气冷却的限制，从而显着减少蒸发冷却的用水量。 本方法通过利用冷却气流和微型自主颤动簧片（AFR）之间的相互作用来诱导冷凝器翅片附近小规模涡旋运动的形成和平流，从而克服了空气侧热传输的限制。 这种方法的一个独特之处在于，簧片颤动是通过利用嵌入冷却气流的机械能来产生的，压力损失的损失极低。 该计划包括综合实验/建模/数值研究，重点关注实施、设计和优化 AFR 使用所需的基础知识，并证明其在改善发电厂配置和运行条件下冷凝器翅片空气侧通道传热特性方面的功效。 佐治亚理工学院的研究将重点关注 AFR 增强的传热特性的实验研究，以及 AFR 技术实现的新型冷凝器配置的建模、设计和测试。 约翰·霍普金斯大学将专注于小规模传热的 CFD 研究以及 AFR 增强型冷凝器配置的性能评估和优化。 AFR 的小规模传热增强最近在佐治亚理工学院的风冷加热管道中得到了证明，具有显着的传热增强效果。 这些低成本的薄簧片可以针对冷凝器的不同区域进行定制，并且可以集成到外部冷凝器表面，也可以作为现有冷凝器的嵌入式改造组件。簧片组件易于安装和维护，无需修改工厂级基础设施。