点击次数：

论文类型：期刊论文

发表时间：2018-02-01

发表刊物：INTERNATIONAL JOURNAL OF THERMAL SCIENCES

收录刊物：SCIE、EI

卷号：124

页面范围：212-226

ISSN号：1290-0729

关键字：Hydrocarbon fuel; BANS model; Buoyancy effect; Heat transfer deterioration; Fuel pyrolysis

摘要：Turbulent heat transfer of hydrocarbon fuels at supercritical pressures exists in many power-generation and propulsion systems. Comprehensive validations and analyses of Reynolds averaged Navier Stokes (RANS) CFD models for supercritical-pressure heat transfer of hydrocarbon fuels, including n-decane and aviation kerosene, have been conducted under a broad range of operation conditions. Results indicate that a CFD model incorporating the standard k-e turbulence model with an enhanced wall treatment works well for supercritical pressure heat transfer of hydrocarbon fuels without buoyancy effect, both with and without fuel pyrolysis. The main weakness of the model is in the inlet region, in which it tends to under-predict the wall temperature at a low inlet Reynolds number. This model is also qualitatively applicable in calculating heat transfer of hydrocarbon fuels in downward flows with buoyancy effect and without fuel pyrolysis. The SST k-omega turbulence model generally produces results very similar to those from the standard k-epsilon turbulence model with an enhanced wall treatment, but in cases of supercritical-pressure heat transfer of aviation kerosene with fuel pyrolysis, it strongly over-predicts the wall temperature in the early inlet region as inlet flow is initially laminar. No turbulence model tested in the present study is applicable in supercritical-pressure heat transfer of hydrocarbon fuels in upward flows with buoyancy effect, in which strong heat transfer deterioration occurs.