The study presents a new type of detonation engine called the Ram-Rotor Detonation Engine(RRDE),which overcomes some of the drawbacks of conventional detonation engines such as pulsed detonation engines,oblique detona...The study presents a new type of detonation engine called the Ram-Rotor Detonation Engine(RRDE),which overcomes some of the drawbacks of conventional detonation engines such as pulsed detonation engines,oblique detonation engines,and rotating detonation engines.The RRDE organizes the processes of reactant compression,detonation combustion,and burned gas expansion in a single rotor,allowing it to achieve an ideal detonation cycle under a wide range of inlet Mach numbers,thus significantly improving the total pressure gain of the propulsion system.The feasibility and performance of RRDE are discussed through theoretical analysis and numerical simulations.The theoretical analysis indicates that the performance of the RRDE is mainly related to the inlet velocity,the rotor rim velocity,and the equivalence ratio of reactant.Increasing the inlet velocity leads to a decrease in the total pressure gain of the RRDE.Once the inlet velocity exceeds the critical value,the engine cannot achieve positive total pressure gain.Increasing the rim velocity can improve the total pressure gain and the thermodynamic cycle efficiency of RRDE.Increasing the equivalence ratio can also improve the thermodynamic cycle efficiency and enhance the total pressure gain at lower inlet velocities.While at higher inlet velocities,increasing the equivalence ratio may reduce the total pressure gain.Numerical simulations are also performed to analyze the detailed flow field structure in RRDE and its variations with the inlet parameters.The simulation results demonstrate that the detonation wave can stably stand in the RRDE and can adapt to the change of the inlet equivalence ratio within a certain range.This study provides the preliminary theoretical basis and design reference for the RRDE.展开更多
A kind of three-dimensional flow-path of the ram-rotor was designed in this paper according to the design method of the typical supersonic intake of aircraft and missiles,especially the design method of the compressio...A kind of three-dimensional flow-path of the ram-rotor was designed in this paper according to the design method of the typical supersonic intake of aircraft and missiles,especially the design method of the compression ramp,the throat and the subsonic diffuser.The design Mach number of the flow-path was based on the averaged relative Mach number,regardless of the change of incoming Mach number along radial direction of the flow-path.Then,the flowfield of the designed flow-path was simulated numerically with computational fluid dynamics software at design point.The purpose of simulation was to obtain the details of the flowfield,including the structure of the shock wave system,position of flow separation zone,and so on.The performance of the ram-rotor was also evaluated.The numerical results show the structure of the shock wave system in the flow-path is similar to that in the supersonic intake.To improve the overall performance of the ram-rotor,the reasonable compromise between the total pressure ratio and the isentropic adiabatic efficiency should be reached.The structure optimization of the flow-path and the configuration of the shock wave system have great influence on the performance of the ram-rotor.展开更多
In order to research the influence of adjustable vane on the aerodynamic performance of the ram-rotor test system, FLUENT soft-ware has been adopted to simulate the flow passage of the ram-rotor test system numericall...In order to research the influence of adjustable vane on the aerodynamic performance of the ram-rotor test system, FLUENT soft-ware has been adopted to simulate the flow passage of the ram-rotor test system numerically. The vane opening is controlled by changing the stagger angle of the vane blades. Results show that flow uniformity of vane outlet is influenced by the vane openings, which has an impact on the aerodynamic loss to some extent. Total pressure ratio, adiabatic efficiency and mass flow rate can be regulated by different openings of the vane. Compared with -8° vane opening, top efficiency of the ram-rotor increases by about 13.8% at ＋6° opening. And total pressure ratio drops by 5.87%. The rising opening increases the relative Mach number at inlet of the ram-rotor and weakens the intensity of the tip clearance leakage, which comes to a decreasing aerodynamic loss.展开更多
A kind of meridional concept which has a shape of contraction-expansion(Con-Exp)was applied to the ram-rotor in the paper,and detailed numerical simulation to understand the impact of meridional shape and geometric ch...A kind of meridional concept which has a shape of contraction-expansion(Con-Exp)was applied to the ram-rotor in the paper,and detailed numerical simulation to understand the impact of meridional shape and geometric characteristic angle on the aerodynamic behavior of ram-rotors has been undertaken.Compared to baseline,there was a positive effect in intensifying shock train and suppressing low momentum fluid in Con-Exp scheme,and the pressure ratio and efficiency of Con-Exp scheme increased by 2.075%and 3.160%,respectively.When the contracting angle was increasing,supersonic flow at and after throat region accelerated remarkably,and the static pressure rise was decreased gradually.The terminating shock train was transformed to terminating shock,and the efficiency of ram-rotor was unfavorable to improve due to low throttle extent.As expanding angle rose,the terminating shock moved forward and turned to shock train gradually.The pressure rise capacity and throttling ability of ram-rotor were raised.More low momentum fluid was accumulated near the middle and upper flow-path,yielding greater flow loss at large expanding angle.展开更多
基金support from the National Natural Science Foundation of China(No.52306152)the China Postdoctoral Science Foundation(No.2023M731912)。
文摘The study presents a new type of detonation engine called the Ram-Rotor Detonation Engine(RRDE),which overcomes some of the drawbacks of conventional detonation engines such as pulsed detonation engines,oblique detonation engines,and rotating detonation engines.The RRDE organizes the processes of reactant compression,detonation combustion,and burned gas expansion in a single rotor,allowing it to achieve an ideal detonation cycle under a wide range of inlet Mach numbers,thus significantly improving the total pressure gain of the propulsion system.The feasibility and performance of RRDE are discussed through theoretical analysis and numerical simulations.The theoretical analysis indicates that the performance of the RRDE is mainly related to the inlet velocity,the rotor rim velocity,and the equivalence ratio of reactant.Increasing the inlet velocity leads to a decrease in the total pressure gain of the RRDE.Once the inlet velocity exceeds the critical value,the engine cannot achieve positive total pressure gain.Increasing the rim velocity can improve the total pressure gain and the thermodynamic cycle efficiency of RRDE.Increasing the equivalence ratio can also improve the thermodynamic cycle efficiency and enhance the total pressure gain at lower inlet velocities.While at higher inlet velocities,increasing the equivalence ratio may reduce the total pressure gain.Numerical simulations are also performed to analyze the detailed flow field structure in RRDE and its variations with the inlet parameters.The simulation results demonstrate that the detonation wave can stably stand in the RRDE and can adapt to the change of the inlet equivalence ratio within a certain range.This study provides the preliminary theoretical basis and design reference for the RRDE.
基金Supported by National High-tech R&D Program(2007AA05Z255)
文摘A kind of three-dimensional flow-path of the ram-rotor was designed in this paper according to the design method of the typical supersonic intake of aircraft and missiles,especially the design method of the compression ramp,the throat and the subsonic diffuser.The design Mach number of the flow-path was based on the averaged relative Mach number,regardless of the change of incoming Mach number along radial direction of the flow-path.Then,the flowfield of the designed flow-path was simulated numerically with computational fluid dynamics software at design point.The purpose of simulation was to obtain the details of the flowfield,including the structure of the shock wave system,position of flow separation zone,and so on.The performance of the ram-rotor was also evaluated.The numerical results show the structure of the shock wave system in the flow-path is similar to that in the supersonic intake.To improve the overall performance of the ram-rotor,the reasonable compromise between the total pressure ratio and the isentropic adiabatic efficiency should be reached.The structure optimization of the flow-path and the configuration of the shock wave system have great influence on the performance of the ram-rotor.
基金supported by the National Natural Science Foundation of China(No.51406022)Liaoning Natural Science Foundation(No.2013020129)+1 种基金Science and Technology Research Project from Education Department of Liaoning Province(No.L2013199)Program for Liaoning Innovative Research Team in University(LT2015004)
文摘In order to research the influence of adjustable vane on the aerodynamic performance of the ram-rotor test system, FLUENT soft-ware has been adopted to simulate the flow passage of the ram-rotor test system numerically. The vane opening is controlled by changing the stagger angle of the vane blades. Results show that flow uniformity of vane outlet is influenced by the vane openings, which has an impact on the aerodynamic loss to some extent. Total pressure ratio, adiabatic efficiency and mass flow rate can be regulated by different openings of the vane. Compared with -8° vane opening, top efficiency of the ram-rotor increases by about 13.8% at ＋6° opening. And total pressure ratio drops by 5.87%. The rising opening increases the relative Mach number at inlet of the ram-rotor and weakens the intensity of the tip clearance leakage, which comes to a decreasing aerodynamic loss.
基金founded by the National Natural Science Foundation of China(No.51406022,No.51436002)the CSC Scholarship(No.201506575024)。
文摘A kind of meridional concept which has a shape of contraction-expansion(Con-Exp)was applied to the ram-rotor in the paper,and detailed numerical simulation to understand the impact of meridional shape and geometric characteristic angle on the aerodynamic behavior of ram-rotors has been undertaken.Compared to baseline,there was a positive effect in intensifying shock train and suppressing low momentum fluid in Con-Exp scheme,and the pressure ratio and efficiency of Con-Exp scheme increased by 2.075%and 3.160%,respectively.When the contracting angle was increasing,supersonic flow at and after throat region accelerated remarkably,and the static pressure rise was decreased gradually.The terminating shock train was transformed to terminating shock,and the efficiency of ram-rotor was unfavorable to improve due to low throttle extent.As expanding angle rose,the terminating shock moved forward and turned to shock train gradually.The pressure rise capacity and throttling ability of ram-rotor were raised.More low momentum fluid was accumulated near the middle and upper flow-path,yielding greater flow loss at large expanding angle.
