Doug Gavic M.S. Graduate Student Mechanical Engineering Room: 1327 ERB Hometown: Oakdale, MN Thesis: Heat Exchanger Design for Supercritical Carbon Dioxide Brayton Cycles

Brayton Cycle for Heat Exchanger Design Primary Heat Exchanger Precooler Recuperator Generator CompressorTurbine Supercritical Carbon Dioxide Water at 15°C from Cooling Tower 600°C Molten Salt from Solar Central Receiver

Objectives Conduct a detailed design study of the Primary, Recuperator, and Precooler heat exchangers Determine the optimal heat exchanger dimensions, geometries and flow configurations needed for this cycle to be realized in practice Assess how pressure drops, fouling, methods of manufacturing, and surface type affect the performance of the heat exchangers

Motivation Compared to conventional Rankine steam cycles, supercritical CO 2 gas turbine cycles offer several possible advantages: – Higher efficiency – Reduced size and complexity – Reduced water usage for cooling High density super-critical carbon dioxide allows for reduced compressor work, increasing efficiency High density also means that machinery can be more compact and simpler, reducing capital/operating costs Using high performance heat exchangers allows for self cooling and heating, reducing water usage and energy costs