The Behavior of Turbulent Heat Transfer Deterioration in Supercritical Hydrocarbon Fuel Flow Considering Thermal Resistance Distribution

To highlight the thermal management of the cooling system in an advanced engine, the flow and heat transfer characteristics of turbulent hydrocarbon fuel flow in a rectangular channel are numerically explored in detail. The severe condition of deteriorated behavior is investigated in the heat transfer process. Considering buoyancy force effects, a three-dimensional numerical model is established and a validated SST k-ω turbulence model is adopted at real working conditions. It is found that there is a strong thermal stratification phenomenon near the heated wall, which sufficiently proves that the splitting up of flow field needs to be considered. The fluctuating characteristics and a relative stable state of flow and heat transfer is performed in the deteriorated and recovery region, respectively. In addition, taking the viscous sublayer and core turbulent field into consideration, a new deteriorated prediction based on the thermal resistance mechanism is proposed and it performed well to evaluate the onset of the deteriorated environment. Under certain conditions, the local deteriorated behavior is strongly related to the form of thermal resistance.