Design and optimization of cooling towers

冷却塔广泛应用于火力发电厂、化工、石化、制冷空调等行业的低品位散热。美国对湿式冷却塔的需求大约是所有家庭用水量的3倍。在寒冷的冬季月份，湿式冷却塔还会在塔顶上方产生可见的凝结蒸汽羽流，这可能会对农业和运输行业(空中和地面)构成威胁，因为能见度降低，甚至在邻近道路上结冰。增加对用水量和羽流能见度的监管，再加上要求在更干旱的条件下开发发电厂，那里没有可靠的补给水来源，太阳能和地热能应用通常就是这种情况，这要求工程师开发工具来设计改进的冷却塔技术。湿式冷却塔的数值模拟和优化，特别是混合式冷却塔，一直不是密集研究的主题。混合塔将不使用蒸发冷却的干冷却与湿冷却相结合，以减少用水量和可见的羽流。在这项提案中，将开发分析和数值模拟工具来研究湿式和混合式冷却塔。研究将集中在填充和羽流区的分析工具，这对湿塔和混合塔都是关键的，以及填充和整个塔的数值工具。数值工具对于研究进水口几何形状、横流下的充填操作和环境条件是必要的。这些数值工具将与优化算法相结合，以能够设计出最优的冷却塔，从而限制电力消耗和水的补充要求。最优设计将在阿尔伯塔大学开发的设施中进行实验测试。该项目的目的是为加拿大的冷却塔行业，特别是国际冷却塔公司，提供继续增长和为加拿大经济做出贡献所需的数值工具和高素质的人员。

Cooling towers are widely used to dissipate the low-grade heat of thermo-electric power plants, chemical and petrochemical process industries, and refrigeration and air conditioning plants. Wet cooling tower requirements in the U.S. are about 3 times larger than all domestic water consumption. During cold winter months, wet cooling tower also produce visible plumes of condensed steam above the tower which can pose threats to agriculture and the transportation industries (air and ground) due to reduced visibility and even ice formation on neighbouring roads. Increased regulations on water consumption and plume visibility, combined with the requirement to develop power plants in more arid conditions where a dependable source of make-up water is unavailable, as it is typically the case for solar thermal and geothermal energy applications, requires engineers to develop tools to design improved cooling tower technologies. Numerical modeling and optimization of wet, and especially hybrid cooling towers, has not been the topic of intense research. Hybrid towers combine dry cooling, which do not exploit evaporative cooling, with wet cooling in order to reduce water requirements and visible plumes. In this proposal, analytical and numerical simulation tools to study wet and hybrid cooling towers will be developed. Research will focus on analytical tools for the fill and plume zone, which are critical to both wet and hybrid towers, and numerical tools for the fill and the entire tower. Numerical tools are necessary to study inlet geometries, fill operation under cross-flow, and environmental conditions. The numerical tools will be integrated with optimization algorithms to be able to design optimal cooling towers that limit power consumption and water make-up requirements. Optimal design will be tested experimentally at facilities that will be developed at the University of Alberta. The aim of the project is to provide the cooling tower industry in Canada, and in particular International Cooling Towers Inc., with the numerical tools and highly qualified personnel required to continue to grow and contribute to the Canadian economy.