压强对凸凹弯曲通道流动与传热的影响OA

In order to investigate the flow,heat transfer,and pyrolysis characteristics of supercritical RP-3 kerosene in convex/concave heated curved channels under different pressures,a numerical simulation method was employed.The Dean number was used to explain the secondary flow intensity.This study clarifies the differences in the flow,heat transfer,and pyrolysis characteristics of RP-3 kerosene in the convex/concave heated sections,and examines the influence of operating pressure on the fuel secondary flow velocity,wall temperature,and RP-3 mass fraction.The results showed that under the pressure of 3 MPa,heat transfer deterioration occurred near the lower wall coupling surface in the convex heated section due to the smaller Dean number of the fuel,causing the wall temperature to rise to a maximum of 1 409 K.In the concave heated section,the change in the direction of centrifugal force led to an increase in the Dean number near the lower wall coupling surface,resulting in a local low temperature at x=57.8 mm on the wall.When the pressure increased from 3 MPa to 5 MPa,the fuel Dean number decreased in both the mainstream region and near the upper wall coupling surface of the convex heated section.Concurrently,the fuel temperature near the lower wall coupling surface decreased,which suppressed the pyrolysis of RP-3 in the near-wall region.In the concave heated section,as the fuel Dean number in the mainstream region was less affected by pressure,the near-wall fuel temperature remained close to the pyrolysis initiation temperature,and the RP-3 mass fraction remained essentially unchanged.