Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-421-2

International Heat Transfer Conference 15
August, 10-15, 2014, Kyoto, Japan

Numerical and Experimental Studies of the Flow and Heat Transfer in Circular Tubes with Straight Frame Rotor Inserts

Get access (open in a dialog) DOI: 10.1615/IHTC15.hte.009123
pages 3883-3893

Abstrakt

The flow resistance and convection heat transfer in circular tubes with rotor inserts were studied numerically and experimentally. The numerical simulation used the MRF model and the moment balance method. The numerical analyses indicate that the large increase in the flow resistance due to the rotor inserts mainly results from the larger solid-liquid contact area and the disturbance of the core flow region. Unlike solid rotor inserts, the straight frame rotors used here increase the velocity gradients near the tube wall which enhances the heat transfer while greatly reducing the increase of the flow resistance due to their hollow structure. Numerical studies were made to develop several kinds of straight frame rotor inserts for experimental studies. The experiments show that the flow resistance in circular tubes with straight frame rotor inserts is only 2~2.5 times that in plain tubes and the heat transfer is enhanced by 30~50%. Among the different rotor insert arrangements, the three-normal-threereverse rotor insert arrangement leads to better flow resistance and heat transfer rates.