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Abstract: The fluid flow of self-rotating twisted-tape inserted tube
is analyzed. According as tangential motion characteristic of fluid in
self-rotating twisted-tape inserted tube, a conception of self-rotating
twisted-tape being dummied as equivalent still twisted-tape is put
forward. A three-dimensional physics and mathematical model of
twisted-tape-inserted tubes are presented. RNG k-e
turbulent model is adopted to simulate flow field and enhanced heat
transfer of heat exchanger tubes with twisted-tape insert numerically.
The distribution laws of the velocity field, pressure field, turbulent
characteristic field and enhanced heat transfer characteristic of
twisted-tape-inserted heat exchanger tubes are obtained. The heat
transfer and pressure drop characteristic of still twisted-tape-inserted
tubes, self-rotating twisted-tape inserted tubes and dummy equivalent
still twisted-tape inserted tubes are compared. The influences of
different twist pitch on enhanced heat transfer and pressure drop are
analyzed. Numerical simulation calculation value of the velocity field
is compared with the experimental data measured by laser doppler
velocimeter (LDV) system. The numerical simulation results show
reasonably good agreement with the experimental results.
Key words: Heat exchanger tube with twisted-tape insert Numerical
simulation Enhanced heat transfer RNG k-e turbulent model
Laser doppler velocimeter
CLC No: TK124
国家教育部科学技术研究重点计划资助项目(00208). Received 20040927, received in revised form
20050201
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