Massively parallel computational methods for combined-modes heat transfer with applications to concentrated solar power technologies

背景：拟议的研究计划是在高效能源系统领域：特别是通过热机械转换的太阳能发电。对该计划的兴趣是由于这样一个事实，即这种技术，虽然主要是必需的，目前仅限于15- 18%的平均年转换效率。这样产生的电力成本可能是使用传统化石燃料产生的电力的三倍。 当转换效率显著提高时，如果这种改进的技术仍然简单、可靠和廉价，太阳能热电厂的竞争力就会出现突破。 所希望的突破可能存在于高温（1，000 °C或以上）联合循环发电厂，燃气和蒸汽涡轮机串联运行，转换效率可达60%，总效率可达30%。在这些温度下提供太阳能热量将涉及重大挑战，例如：设计高温材料，优化接收器和光学器件中的辐射和对流传热，以实现高集中。 结论：本研究计划的主要目标是： 1)研究多孔材料，更具体地说，半透明网状陶瓷材料在高压气流下对聚集太阳能的体积吸收的基本原理，然后; 2)创建“数值”或虚拟网状多孔陶瓷，以通过计算手段进行研究，同时; 3)制定，实施和验证多孔介质中流体流动模拟的数值方法，同时; 4)制定、实施和验证多孔介质中组合模式传热的数值方法，然后; 5)联合收割机对上述虚拟陶瓷进行了研究; 6)实验测试按优化设计构建的真实的陶瓷的转换性能，同时; 7)基于格子玻尔兹曼方法重新制定部分主代码，理论上需要这样做来提高计算时间。 结果：本研究的成果将有助于正确理解光热转换单元（容积式吸收器）在全球技术中的关键地位。 我国与世界其他国家沿着将在今后几十年面临能源危机;在这方面，热能工程研究有可能导致为加拿大开发新的重要能源和环境技术。

CONTEXT: The proposed research program is in the field of high-efficiency energy systems: in particular, solar-electricity production by thermo-mechanical conversion. The interest in the program is motivated by the fact that such technology, although mostly required, is currently limited to an average annual conversion efficiency of 15-18%. The cost of electricity thusly produced may be as much as three times that of electricity produced using conventional fossil fuels. A breakthrough in the competitiveness of solar-thermal plants will occur when the conversion efficiency will be significantly increased, and if this improved technology could still be simple, reliable and inexpensive. The desired breakthrough may reside in high-temperature (1,000°C or above) combined-cycle power plants, with gas and steam turbines operating in series, for which the conversion efficiency could reach 60% and the overall efficiency up to 30%. Providing solar heat at these temperatures would involve significant challenges, such as: designing materials for high temperatures, optimizing radiative and convective heat transfer in receivers and optics for high-concentration. OBJECTIVES: The main objectives of this research program are to: 1) study the fundamentals of the volumetric absorption of concentrated solar energy on porous materials, more specifically, semi-transparent reticulated ceramic materials subjected to high-pressure air flows, and then; 2) create “numerical” or virtual reticulated porous ceramics to be investigated by computational means, and simultaneously; 3) formulate, implement and validate a numerical method for fluid flow simulations in porous media, and simultaneously; 4) formulate, implement and validate a numerical method for combined-modes of heat transfer in porous media, and then; 5) combine both methods to investigate the above-mentioned virtual ceramics, and then; 6) experimentally test the conversion performances of real ceramics constructed according to the optimal design, and simultaneously; 7) reformulate parts of the main code based on Lattice Boltzmann methods, which in theory, are required to enhance computational time. OUTCOMES : Outcomes from this research will be a proper understanding of the key of optico-thermal conversion unit (the volumetric absorber) in the global technology. Our country, along with the rest of the world, will face an energy crisis in the decades to come; in this context, research in thermal-energy engineering could potentially lead to the development of new and vital energy and environmental technologies for Canada.