In order to meet the demand of CubeSats for low power and high-performance micro-propulsion system,a porous ionic liquid electrospray thruster prototype is developed in this study.1010 conical emitter arrays are fabri...In order to meet the demand of CubeSats for low power and high-performance micro-propulsion system,a porous ionic liquid electrospray thruster prototype is developed in this study.1010 conical emitter arrays are fabricated on an area of 3.24 cm^(2) by computer numerical control machining technology.The propellant is 1-ethyl-3-methylimidazolium tetrafluoroborate.The over-all dimension of the assembled prototype is 3 cm×3 cm×1 cm,with a total weight of about 15 g(with propellant).The performance of this prototype is tested under vacuum.The results show that it can work in the voltage range of±2.0 kV to±3.0 kV,and the maximum emission current and input power are about 355 lA and 1.12 W.Time of Flight(TOF)mass spectrometry results show that cationic monomers and dimers dominate the beam in positive mode,while a higher proportion of higher-order solvated ion clusters in negative mode.The maximum specific impulse is 2992 s in positive mode and 849 s in negative mode.The thrust is measured in two methods:one is calculated by TOF results and the other is directly measured by high-precision torsional thrust stand.The thrust(T)obtained by these two methods conforms to a certain scaling law with respect to the emis-sion current(I_(em))and the applied voltage(V_(app)),following the scale of T-Iem_(Vapp)^(0.5),and the thrust range is from 2.1 lN to 42.6 lN.Many thruster performance parameters are significantly different in positive and negative modes.We speculate that due to the higher solvation energy of the anion,more solvated ion clusters are formed rather than pure ions under the same electric field.It may help to improve thruster performance if porous materials with smaller pore sizes are used as reservoirs.Although there are still many problems,most of the performance parameters of ILET-3 are good,which can theoretically meet the requirements of CubeSats for micro-propulsion system.展开更多
On May 28, the 120-ton thrust liquid-oxygen/kerosene engine developed by the Academy of Aerospace Liquid Propulsion Technology (AALPT) passed the acceptance test organized by China National Space Administration (CNSA)...On May 28, the 120-ton thrust liquid-oxygen/kerosene engine developed by the Academy of Aerospace Liquid Propulsion Technology (AALPT) passed the acceptance test organized by China National Space Administration (CNSA). The 120-ton thrust liquid-oxygen/kerosene engine is a non-pollution, non-toxic, high performance and reliable basic pro-展开更多
A prototype of impulse thruster for radial thrust trajectory correction munitions is designed. It adopts semiconductor bridge (SCB) as ignition element,Ti/KClO4 (TK) as ignition charge and ammonium perchlorate/alumini...A prototype of impulse thruster for radial thrust trajectory correction munitions is designed. It adopts semiconductor bridge (SCB) as ignition element,Ti/KClO4 (TK) as ignition charge and ammonium perchlorate/aluminium (NA) or potassium picate/RDX (KR) as main charge. A thrust test device of impulse thruster is also designed. The output performance of the impulse thruster prototype is tested by the device. The tested results show that it can meet the safety requirements of 1A1W/5 min no-fire level and produce 0.2-0.6 N·s thrust impulse within 3ms of action time under certain test conditions; the corresponding ignition delay time is less than 0.5 ms.展开更多
An evaluation method of trial tests will be presented which is based on propeller characteristic functions provided by open water tests.Main reference quantity is the rate of revolutions which is constant during one t...An evaluation method of trial tests will be presented which is based on propeller characteristic functions provided by open water tests.Main reference quantity is the rate of revolutions which is constant during one trial double run and reliably to measure and,furthermore,the basic quantity of the mathematical adjustment of the hydrodynamically coupled test quantities by means of regression analysis.Using this physical plausible analysis of the trial test data and the propeller open water diagram an evaluation of current speed and ship’s speed through the water is possible.Assumed that thrust deduction fraction and relative rotative efficiency are scale independent,speed and power under contract conditions may be calculated at constant propeller speed where the results are corrected with respect to wind and waves using the linear dependance of speed and power at moderate differences of propeller load.展开更多
基金supported by the National Key R&D Program of China(No.2020YFC2201103).
文摘In order to meet the demand of CubeSats for low power and high-performance micro-propulsion system,a porous ionic liquid electrospray thruster prototype is developed in this study.1010 conical emitter arrays are fabricated on an area of 3.24 cm^(2) by computer numerical control machining technology.The propellant is 1-ethyl-3-methylimidazolium tetrafluoroborate.The over-all dimension of the assembled prototype is 3 cm×3 cm×1 cm,with a total weight of about 15 g(with propellant).The performance of this prototype is tested under vacuum.The results show that it can work in the voltage range of±2.0 kV to±3.0 kV,and the maximum emission current and input power are about 355 lA and 1.12 W.Time of Flight(TOF)mass spectrometry results show that cationic monomers and dimers dominate the beam in positive mode,while a higher proportion of higher-order solvated ion clusters in negative mode.The maximum specific impulse is 2992 s in positive mode and 849 s in negative mode.The thrust is measured in two methods:one is calculated by TOF results and the other is directly measured by high-precision torsional thrust stand.The thrust(T)obtained by these two methods conforms to a certain scaling law with respect to the emis-sion current(I_(em))and the applied voltage(V_(app)),following the scale of T-Iem_(Vapp)^(0.5),and the thrust range is from 2.1 lN to 42.6 lN.Many thruster performance parameters are significantly different in positive and negative modes.We speculate that due to the higher solvation energy of the anion,more solvated ion clusters are formed rather than pure ions under the same electric field.It may help to improve thruster performance if porous materials with smaller pore sizes are used as reservoirs.Although there are still many problems,most of the performance parameters of ILET-3 are good,which can theoretically meet the requirements of CubeSats for micro-propulsion system.
文摘On May 28, the 120-ton thrust liquid-oxygen/kerosene engine developed by the Academy of Aerospace Liquid Propulsion Technology (AALPT) passed the acceptance test organized by China National Space Administration (CNSA). The 120-ton thrust liquid-oxygen/kerosene engine is a non-pollution, non-toxic, high performance and reliable basic pro-
基金the Ministerial Level Advanced Research Foundation (51305080302)
文摘A prototype of impulse thruster for radial thrust trajectory correction munitions is designed. It adopts semiconductor bridge (SCB) as ignition element,Ti/KClO4 (TK) as ignition charge and ammonium perchlorate/aluminium (NA) or potassium picate/RDX (KR) as main charge. A thrust test device of impulse thruster is also designed. The output performance of the impulse thruster prototype is tested by the device. The tested results show that it can meet the safety requirements of 1A1W/5 min no-fire level and produce 0.2-0.6 N·s thrust impulse within 3ms of action time under certain test conditions; the corresponding ignition delay time is less than 0.5 ms.
文摘An evaluation method of trial tests will be presented which is based on propeller characteristic functions provided by open water tests.Main reference quantity is the rate of revolutions which is constant during one trial double run and reliably to measure and,furthermore,the basic quantity of the mathematical adjustment of the hydrodynamically coupled test quantities by means of regression analysis.Using this physical plausible analysis of the trial test data and the propeller open water diagram an evaluation of current speed and ship’s speed through the water is possible.Assumed that thrust deduction fraction and relative rotative efficiency are scale independent,speed and power under contract conditions may be calculated at constant propeller speed where the results are corrected with respect to wind and waves using the linear dependance of speed and power at moderate differences of propeller load.