Abstract
Compact brazed heat exchangers (BHEs) are used in many industrial products, e.g., in refrigerators and heat pumps. Many studies have been conducted on the boiling in BHEs employing Freon or carbon dioxide as the working fluid. Moreover, a thermal conversion system that works using the small temperature difference has attracted attention as a renewable source of energy e.g., ocean thermal energy conversion. These systems mostly employ ammonia as a working fluid. For miniaturizing this system, the use of BHEs as heat exchangers is suggested. However, the boiling characteristics of ammonia in BHEs have not been clarified. Therefore, the overall heat transfer and boiling heat transfer coefficient of ammonia are measured in this study. In addition, the heat transfer performance of the BHE is clarified under varying experimental conditions.
