Summary: | 碩士 === 逢甲大學 === 機械工程學所 === 91 === ABSTRACT
The objective of the present study is to investigate heat transfer characteristics in a rotor-stator disk system with rim seal by using a heat transfer measurement. This experiment is performed by using a data acquisition system with wireless data transmission modules. Considering a detailed heat loss analysis and data reduction, the local Nusselt numbers can be appropriately evaluated. The heat transfer characteristics of a shrouded rotor-stator are explored for various values of gap ratio, cooling flow Reynolds number, and rotational Reynolds number. Two different rotational modes of the rotor-stator system are also considered. The results show that the local Nusselt numbers of the disks increase with decreasing gap ratio and then increase with increasing cooling flow Reynolds number and rotational Reynolds number. However, the effect of gap ratio on the local Nusselt numbers decrease with increasing disk rotational speed. Owing to the cooling flow speed increase with decreasing gap ratio then reduce rotational Reynolds number effect on the Nusselt numbers. For different modes of the rotor-stator system, the results disclose that both the rotational effect and cooling flow effect are the significant factors to the heat transfer performance. In practical applications, the results are helpful in cooling design of turbine disks and also valuable reference resources for design of other rotating machinery and thermal systems.
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