Numerical Study On Effects Of Dragreducing Additives On Supercritical Flow And Heat Transfer Characteristics Of Kerosene

With the rapid development of China's space industry,the rocket's carrying capacity can no longer meet the needs of the space industry.The pressure staged combustion Lox/kerosene rocket engine is a new model developed in China.The cooling of the thrust chamber adopts regenerative cooling technology.In the channel,the coolant kerosene is at supercritical pressure.The pressure loss is huge and it cause unnecessary loss of energy.Using drag reducers can reduce energy consumption and save power.The application of drag reducers has good prospects in the aerospace field.In this paper,the numerical investigation on the flow and heat transfer of kerosene with/without drag-reducing additive was achieved with computational fluid dynamics software FLUENT.First of all,a ten-component alternative model was used to describe the physical properties of kerosene,the calculation of supercritical properties of kerosene was performed using physical property calculation software.The accuracy of the ten-component alternative model was verified by comparison with the physical property test data of kerosene.The verification of the accuracy of numerical simulation method was based on the comparison with experimental data under supercritical pressure conditions.Secondly,based on the accuracy of the verification of the physical properties of the kerosene and numerical methods,the physical model of the cooling channel was designed according to the size and material properties of the actual cooling channel.The key factors affecting the flow and heat transfer characteristics of kerosene were numerically simulated.The pressure drop,wall temperature,kerosene temperature and heat transfer coefficient were analyzed under the conditions of different inlet velocity,wall heat flow,inlet temperature and outlet pressure,and the characteristics of supercritical fluid flow and heat transfer were obtained.Then,the kerosene solution with polymer was measured with a rotating rheometer,and the curves of the viscosity of the polymer kerosene solution with the shear rate were obtained.The shear dilute characteristics of the polymer kerosene with a typical nonNewtonian fluid were found.The parameters of the non-Newtonian fluid Carreau model were obtained.Comparing with experimental data,it was found that the model was applicable.Finally,the flow and heat transfer of kerosene under different conditions were numerically simulated based on Reynolds-stress turbulent model.The friction coefficient,wall temperature and flow rate of the polymer kerosene solution were obtained.Compared with the flow and heat exchange of kerosene under the same conditions,parameters such as drag reduction rate and heat transfer rate were obtained.The influence of drag-reducing additive on the flow and heat transfer characteristics of kerosene under supercritical pressure was mastered.