Experimental investigation of scroll expander for micro and small organic Rankine cycle electrothermal conversion

• Main Authors: Ting-Ying Su, 蘇廷穎
• Other Authors: Tzu-Chen Hung
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/4ctnwd

碩士 === 國立臺北科技大學 === 機電整合研究所 === 104 === The thesis focus on organic Rankine cycle(ORC) power generation system using R245fa as working fluid to investigate expander performance. Two systems are built for different heat source application. KNT030, which is expect to generate 3kW electrical power, is focus on heat source temperature range from 80˚C to 110˚C and from 20kW to 40kW of usable heat；KNT100, which is expect to generate 10kW electrical power, is focus on heat source temperature range from 100˚C to 120˚C and from 60kW to 120kW of usable heat. Both system use scroll expander due to heat source conditions, and three kind of experiment are plan to simulated industrial waste heat. Change system heat input can find suitable operation condition. When heat source temperature is fixed and flow rate is increased, expander can generate more electrical power, but electricity consumption increased and expander efficiency changed at the same time. When facing insufficient cooling water flow rate situation, cycle thermal efficiency drop severely. If cooling water is too much, it will waste its cooling ability. These experiments are valuable reference to industrial waste heat recovery application. Grid-connect and stand-alone generator mode is also compared. Grid-connect mode will fix the expander rotational speed as stand-alone mode expander rotational speed is decide by system condition. By ideal expansion, over expansion and under expansion of expander condition, operation condition and expander performance are evaluated whether the operation condition is suitable to expander or not. Volumetric ratio is also analyzed.