Applications of STAR-CD on Simulation of Flow Field Inside an Exhaust Chamber of a Scroll Compressor and the Ventilation Efficiency in ZPRL Building

• Main Authors: Ker-Hsun Liao, 廖克勳
• Other Authors: Chiun-Hsun Chen
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/40137558858079878928

碩士 === 國立交通大學 === 機械工程系 === 88 === This thesis utilizes a commercial code, SATR-CD, to simulate the flow field for two subjects. The first one is the flow field inside an exhaust chamber of a scroll compressor, the other is the ventilation flow inside a building of ZPRL (Zero Power Reactor at Lungtan). The computed results of the first part show that the refrigerant from discharge port enters the exhaust chamber, and the center of top cover becomes the high-pressure area due to the main flow direct impingement. After that, it flows out the chamber through the exhaust pipe. If a check valve is placed in the chamber, then, the main stream will directly impinge its top surface, resulting in a high pressure inside the check valve. The stream then flows out the check valve to the exhaust chamber. Not subjected to the flow impingement directly, the pressure of top cover becomes lower and its distribution more uniform. Finally, a successive flow variation history can be observed by an animation by using the transient flow simulation of STAR-CD. In the second part, the simulation results find that there exist many small vortices at corners in the building for its original design. After three additional experimental rooms are set up in the original building, the space of flow path is limited. Therefore, the re-circulation flows are occurred at the corners and wall surfaces along these additional experiment rooms. The velocities of flow are slightly decreased accordingly. The flow velocities in the third floor are found relatively small and its pressure distribution becomes more uniform. Comparing the results obtained from the four case studies, it can be concluded that the arrangement of space has a much greater influence on the flow structure than that of the total ventilation flow rate in the range of 5000 to 10000 cfm.