2021 Vol. 36, No. 1

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Integrated thermal protection and power generation system of hypersonic vehicle engine
JIANG Peixue, ZHANG Fuzhen, XU Ruina, ZHU Yinhai
2021, 36(1): 1-7. doi: 10.13224/j.cnki.jasp.2021.01.001
Abstract PDF(2145KB) icon977 icon559
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Considering the thermal protection of hypersonic vehicle and the power demand of airborne equipment, based on the optimization of engine energy management, an integrated system of high temperature power generation and high efficiency thermal protection was proposed with supercritical CO2 as the circulating working fluid combined with CO2 physical characteristics. This integrated scheme can provide electricity and reduce the fuel carrying capacity on the premise of achieving thermal protection purpose. The measures to improve the performance of the integrated system were put forward by analyzing the integrated system based on the fuel as the sole heat sink: to maximize the temperature of the fuel heated in the CO2cooler and improve the performance of the CO2 closed Brayton cycle by using regeneration. The thermal efficiency of the system can reach 17%. When the flight time was 30 minutes, compared with battery and fuel cell, the net mass gain of the integrated system was reduced by 85% and 68%, and the volume was reduced by 81% and 59%.
Influnce of environment parameters on anti-icing heat load for aircraft
NI Zhangsong, LIU Senyun, ZHANG Jun, WANG Mao, WANG Zixu
2021, 36(1): 8-14. doi: 10.13224/j.cnki.jasp.2021.01.002
Abstract PDF(2932KB) icon460 icon277
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To accurately calculate the surface heat load for the design of the anti-icing system of an aircraft, the method for calculation of anti-icing heat load was studied and the calculation process was presented. And the influnce of the incoming flow speed, flight altitude, temperature, liquid water content and median volumetric diameter on the surface heat load distribution was studied. The results showed that: (1) the heat load was mainly located at the leading edge of the wing, and the closer to the tip of the wing, the larger the heat load value. The heat load curve had a trough in the middle and two shoulders at each side. (2) The non-zero range and the amplitude of the surface heat load were in proportion to the incoming flow speed and water median volumetric diameter. The variation of the flight altitude had trivial influence. As the incoming flow temperature decreased or liquid water content increased, the amplitude of the heat load increased, but the distribution range of the curve remained the same. The distribution range of the heat load on upper wing surface increased about 50% as the diameter of the water droplet increased 10 μm.
Effect of composition variance on methane oxidation characteristics
ZHENG Weilin, PANG Liyao, ZHANG Shijie, XIE Fan, ZENG Wen
2021, 36(1): 15-24. doi: 10.13224/j.cnki.jasp.2021.01.003
Abstract PDF(5747KB) icon309 icon213
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The methane oxidation within the temperature range of 850-1 300 K and atmospheric pressure was studied in a jet stirred reactor. The major reactants (CH4, O2), intermediate components (C2H6, C2H4, C2H2, H) and pollutants (CO, CO2) were measured by gas chromatography under the condition of equivalence ratio range of 02-2, oxygen content of 2%-8%, carbon dioxide content of 0-20%, water vapor content of 0-20%. The effects of various compositions on species distributions during methane oxidation were analyzed in detail. It was found that the concentration of intermediate components increased with the increase of equivalence ratio and oxygen content; the increase of carbon dioxide content had a weak inhibitory effect on the formation of intermediate products, but resulted in obvious rise of the concentration of pollutants; the increase of water vapor content led to significant increase of hydrogen production, and promoted the formation of carbon monoxide, but had little effect on the formation of carbon dioxide.
Spark ignition model for combustor
XIAO Wei, JIANG Lijun, CHEN Sheng
2021, 36(1): 25-33. doi: 10.13224/j.cnki.jasp.2021.01.004
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With an aim to develop an ignition model and obtain the key factors influencing the ignition limits in aero-engine combustor, testing and theoretical investigations were conducted based on the ignition process inside a single dome gas turbine combustor. The characteristic curve of ignition process was obtained, and a method to optimize the ignition performance was also proposed. An ignition model to predict the ignition limits was developed based on the concept of recovery time, and the accuracy of the prediction model was validated. It is found that the significant improvement in ignition performance can be obtained by decreasing the atmozation performance of nozzle. A very satisfactory agreement is demonstrated between the predictions based on the prediction model and the actual measured values. The maximum error of the prediction model is less than 20%, which is qualified to meet the requirements of the combustor design.
Flow and heat transfer characteristics in roughened rotating wedge-shaped channel with pin-fins
LI Jie, TIAN Shuqing, YANG Meisong, DENG Hongwu
2021, 36(1): 34-41. doi: 10.13224/j.cnki.jasp.2021.01.005
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The trailing edge of the turbine rotor blades featured lateral extraction and the fin-pins were subject to Coriolis, centrifugal force, and induced buoyancy. Experimental methods were used to study its heat transfer and flow resistance characteristics within the parameters of the actual working conditions: Reynolds number and rotation number ranging from 20 000 to 45 000 and 0 to 0155, respectively. The experimental results showed that the presence of the pin-fins made the bottom stagnation area larger, whereas it also significantly improved the heat transfer in the middle radius. The ratio of the flow resistance and the thermal performance decreased with the Reynolds number. However, the rotation enhanced the heat transfer at the top and weakened that at the bottom. In general, the rotation increased the flow resistance, while the average heat transfer and the thermal performance were deteriorated.
Local pressure drop and flow resistance characteristic at entrance of tubed vortex reducer
ZHAO Yizhen, WEI Song, MAO Junkui
2021, 36(1): 42-52. doi: 10.13224/j.cnki.jasp.2021.01.006
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The flow structure and flow loss characteristic in a rotating cavity with tubed vortex reducer were studied numerically. The study focused on the mechanism of the tubed vortex reducer, especially the local loss characteristic at the tube entrance under different geometric parameters of the tube. Based on these studies, a mathematical model for predicting the pressure drop in a tubed cavity was established. It was found that the local loss characteristics at the tube entrance were related to the flow state before the entrance, and the incident angle can describe this flow state well. The static pressure loss at the tube entrance cannot be ignored, accounting for about 11% of the total static pressure drop in the rotating cavity. Furthermore, the tube with a moderate-length can restrict the rotation of the air and reduce the pressure drop in the rotating cavity more effectively. Under the research conditions, the tubed vortex reducer with the optimal tube length can reduce the local pressure drop at the tube entrance by about 25% and the overall static pressure drop in the cavity by about 10%. This also showed that, the mathematical model can provide accurate results of the static pressure distribution in the tubed vortex reducer. The average error was about 53% between the CFD results and the mathematical model results.
Experiment of turbulent flow in rotating ribbed channel with TR-PIV
SHI Jincheng, HU Songjun, YOU Ruquan, LI Haiwang, XIA Shuangzhi
2021, 36(1): 53-60. doi: 10.13224/j.cnki.jasp.2021.01.007
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The mainstream averaged velocity, Reynolds stress and the reattachment point were measured in rotating ribbed channel with time-resolved particle image velocimetry(TR-PIV), and their change rule along the channel was studied. The aspect ratio of channel was 1, the blockage ratio of rib was 01, the Reynolds number was set to 10 000, and the rotation numbers ranged from 0 to 052. The experimental results showed that: the flow was symmetrical in static conditions, but Coriolis force generated by rotation would greatly affect the flow. With the increase of the rotating speed, the mainflow velocity pattern was inclined to the trailing side, the vortices structure on the leading side increased, and the attachment point moved backward, while the trailing side was just the opposite, and this trend would develop along the path; the Reynolds stress near the leading side became weaker, while the trailing side became stronger, and the extreme value of the Reynolds stress along the channel was basically the same, but the region would expand downstream.
Numerical investigation on flow and heat transfer of beveled pin-fins based on airfoil profile in a cooling channel
JIA Ning, JIN Wei, WU Junmei
2021, 36(1): 61-69. doi: 10.13224/j.cnki.jasp.2021.01.008
Abstract PDF(4771KB) icon438 icon218
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Based on NACA airfoil profile and the structure of beveled vortice generator, a novel beveled design of NACA pin-fin and its configuration in the cooling channel of turbine blade were proposed. Numerical simulation was conducted to investigate the flow and heat transfer characteristics of this pin-fin arrays in the cooling channel. The detailed physical field distributions of the flow and heat transfer were discussed and the overall thermal performance was also explored. The result indicated that the bevel cut of the pin-fin can produce lasting and stable longitudinal vortices to strengthen the disturbance of flow field, yielding a good effect on enhancing heat transfer of the cooling channel.
Numerical investigation on effect of rotation on flow and heat transfer of impinging jets
CAI Xuecheng, LI Qin, YANG Xuesen, DONG Wei
2021, 36(1): 70-77. doi: 10.13224/j.cnki.jasp.2021.01.009
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In order to explore the effects of rotation on impinging jets flow and heat transfer characteristics of the blade leading edge, the flow structure and heat transfer distribution were studied by numerical method. Furthermore, the differences between the stationary condition and three rotation speeds were compared and analyzed. Results showed that the target average Nusselt number decreased with the increase of the rotation speed. At the highest rotation speed, the target average Nusselt number was reduced by 16%. On the other hand, the sensitivity of pressure side and suction side to rotation was different. At high rotation speed, the decrement of heat transfer was mainly concentrated on the entire suction side and the area where the dimensionless curve length s/d was less than 2 on the pressure side, while the heat transfer in the area where s/d was greater than 2 on the pressure side was slightly enhanced. Rotation had a significant effect on the flow structure. The mass flow distribution of the jet holes was changed by rotation, and Coriolis forces deflected jets to the pressure side. This feature became more pronounced with the increase of rotating speed. In addition, the centrifugal force in the rotating channel changed the local intensity of crossflow.
Improved dissipative model of hydrodynamic in tube
XU Binbin, WANG Xue, WU Chaojun, ZENG Weiping, YAN Lai, LAN Yu, ZHU Renyu
2021, 36(1): 78-87. doi: 10.13224/j.cnki.jasp.2021.01.010
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Based on the two-dimensional hydrodynamics equations and the real flow boundary condition at the inlet of tube, an improved dissipative model was proposed. Compared with the dissipative model, the improved one taking the speed of flow field into account can describe the effect of tube on measuring dynamic pressure more accurately in wind tunnel test. The experiments in FL-14 wind tunnel also indicated that the improved dissipative model can dramatically reduce the measuring error compared with the dissipative model. The relative error of 534% resulting from the correction via dissipative model decreased to 66% via the improved dissipative model at certain experimental conditions.
Design and test verification of small loitering munition electric-powered propulsion system
WU Chao, YUAN Xianshi, XUE Jinguang, CHE Xiaotao, WANG Gang, LI Shunfeng
2021, 36(1): 88-96. doi: 10.13224/j.cnki.jasp.2021.01.011
Abstract PDF(3831KB) icon642 icon269
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To obtain an electric-powered propulsion system meeting the engineering requirement of small loitering munition, the vortex theory and the first-order motor model were used to establish the efficiency calculation model of the electric-powered propulsion system. The parameters of the propeller and motor were quickly designed by taking the efficiency of the electric-powered propulsion system at cruise as the objective, and the thrust and maximum counter torque in climb as constraints. According to the indicators of motor and propeller, the motor dynamometer test was carried out and the motor selection was completed, the propeller parameters were optimally designed in detail by using the Kriging agent model, and complete aerodynamic parameters were calculated. The wind tunnel test was carried out for the electric-powered propulsion system of the small loitering munition. The results showed that the deviation between the theoretical calculation and the test of propeller was within 85%, the deviation between the design and test results for the efficiency of the electric-powered propulsion system at cruise was within 27%, showing that the design method of the electric-powered propulsion system is reasonable and effective, thus providing a reference for the design of small loitering munition.
Influence of exhaust gas ingestion on engine inlet distortion
WANG Junqi, WANG Tao, LIU Yu
2021, 36(1): 97-103. doi: 10.13224/j.cnki.jasp.2021.01.012
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In order to understand the distortion characteristics of the engine inlet face due to exhaust gas ingestion, a ground test was done to acquire the total pressure and total temperature data of the engine inlet face. Based on the measurement data, an analytical study on the features of the temperature and pressure distortion and the influences on the temperature distortion intensity were carried out. The results showed that the deflected exhaust gas can be ingested by the inlet, which could produce a temperature distortion on the engine inlet face, in this situation the flow field on the engine inlet face was a combination of temperature and pressure distortion. The hot exhaust gas ingestion can raise the pressure in the low pressure region on the engine inlet face, and lower the steady pressure distortion. As the engine working thrust lever was improved and the working time was increased, the temperature distortion intensity peak was higher. The change of the temperature flow field lagged behind that of throttle, indicating a dynamic changing flow field, but the temperature rise rate was relatively low.
Design of target propeller slipstream under propeller-wing interaction
XUE Chen, ZHOU Zhou, FAN Zhongyun, LI Xu
2021, 36(1): 104-118. doi: 10.13224/j.cnki.jasp.2021.01.013
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For the multi-propeller aircraft with distributed electric propulsion (DEP) configuration, a method to improve the lift-to-drag ratio of the wing was developed by optimizing the propeller slipstream. A propeller design method which can obtain the target induced velocity distribution was proposed. Based on the panel method, an aerodynamic program Prop-wing that can quickly calculate the propeller-wing interference was developed. An efficient optimization method based on Kriging surrogate model was established to obtain the optimal induced velocity distribution and raise the lift-to-drag ratio of the wing. The optimization results showed that the larger axial induced velocity near the propeller hub meant the larger lift drag ratio of the downstream wing. When the power of the propeller was not limited, the optimized propeller can reduce the drag of the downstream wing-segment by 1875% and increase the lift-to-drag ratio of wing-segment by 2563% compared with the propeller with the minimum energy loss; when the power of the optimized propeller was limited, the lift-to-drag ratio of the wing-segment increased to 962%. Although the lift-to-drag ratio is raised at the cost of propeller efficiency reduction, the research still provides an idea for the use of distributed propeller slipstream.
Hover performance of helicopter main and tail rotors with swirl velocities
YANG Kelong, HAN Dong
2021, 36(1): 119-129. doi: 10.13224/j.cnki.jasp.2021.01.014
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It is important to quickly predict the hover performance of main and tail rotors with sufficient precision for helicopter design. To investigate the effects of swirl velocities on the hover performance of main and tail rotors, and give a better prediction for the hover performance, a flight performance model was derived and a swirl velocity model was coupled into it. The test data of the UH-60A helicopter were used for validation. When the blade loading coefficient of the main rotor was higher than 005, the effects of the swirl velocities on the main rotor power became significant. The swirl velocities increased the profile torque of the main rotor. The increased torque required the tail rotor to produce more thrust with more power consumption. At a higher blade loading coefficient of the main rotor of 012, the swirl velocities increased the main rotor power, tail rotor power and total power by 380%, 524% and 508%, respectively. The profile power increase of the main rotor caused by the profile swirl velocity was less than that of the induced swirl velocity, but the power increase was higher at high rotor blade loadings. Considering the swirl velocities in the main rotor can improve the prediction precision of the hover performance, especially at high blade loadings
Flying qualities analysis for helicopter-slung load control system
NIE Wensong, CAO Yihua, LI Qiang
2021, 36(1): 130-136. doi: 10.13224/j.cnki.jasp.2021.01.015
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Three helicopter-slung load control systems were developed to study the effect of slung load on helicopter’s flying qualities, based on command filter system, PID control and dynamic inverse control. Control system were investigated using simulation and frequency domain analysis according to the requirements presented by ADS-33E and flying qualities criteria for rotorcraft with slung load. Subsequently, the effect of slung load mass and sling length on helicopter flying qualities was analyzed. The result showed that the load state feedback can improve helicopter’s handling qualities, the gain margin reached 126 dB and the bandwidth was 331 rad/s. The lagged cable angle feedback can damp the load swing effectively at the cost of getting the bandwidth down to 062 rad/s, and the helicopter with a long sling and heavy load may get poor flying qualities.
Improving fatigue performance of titanium alloy simulated-blade subjected to foreign object damage by laser shock peening
NIE Xiangfan, WEI Chen, HOU Zhiwei, TANG Yuyuan, HE Weifeng
2021, 36(1): 137-147. doi: 10.13224/j.cnki.jasp.2021.01.016
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In order to design appropriate technics for solving foreign object damage (FOD) problem, a simulated-blade was designed according to aero-engine compressor blade size characteristics, then pre-treated by two laser shock strengthening processes, and impacted by air gun system. The effect rule and strengthening mechanism on fatigue performance were analyzed by high-cycle axial fatigue tests and stress field analysis. Test results indicated that fatigue strength of simulated-blade decreased from 51845 MPa to 29072 MPa subjected to foreign object damage. When pre-treated by laser shock peening with 5 J and 7 J, fatigue strength was improved to 34449 MPa and 37493 MPa, respectively. The introduction of high compressive residual stress field by laser shock peening greatly improved the local stress field distribution in the damage area, which not only significantly improved the fatigue strength of the simulated blade, but also increased the deviation of fatigue notch factor. With these two technics, the greater laser energy means the greater residual stress value and depth, helping to reduce more effectively the amplitude of the equivalent stress intensity factor in the crack propagation process, and bring about the greater increase of fatigue strength and fatigue notch factor deviation of the damaged simulated blade.
Multi-objective optimization design of layouts parameters for irregular pipeline on engine case
LIU Wei, ZHU Hongyan, ZHAO Yujie, YUE Zhufeng
2021, 36(1): 148-156. doi: 10.13224/j.cnki.jasp.2021.01.017
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Optimization design of pipeline layout is an important means to reduce the vibration stress of engine pipeline. The multi-objective optimization design process and method for the layout parameters of the irregular pipeline were proposed. Based on the U-shaped pipeline with curved surface of engine case, a parameterized modeling method of an irregular pipeline with complex layout was established. The sensitivities of layout parameters to the dangerous natural frequencies and multi-point excitation response of the pipeline, such as the resonance frequencies, the maximum displacement and stress amplitude under multi-point excitation, were analyzed. In view of the constraints of multi-frequency and vibration responses, the method of multi-objective genetic algorithm was adopted to realize the optimal design of layout parameters of irregular pipeline. The results showed that the optimization of layouts was effective, two forbidden bands of dangerous natural frequencies were staggered. Under the same excitation, the maximum displacement amplitude of pipeline structure decreased about 35%, and the maximum stress amplitude decreased nearly 50%. It can provide a reference for the vibration controlling and dynamic forward design system of engine pipeline.
Qualification test risk analysis of binomial equipmentbased on Bayes theory
LI Dawei, WANG Guodong, LI Yongzhe
2021, 36(1): 157-166. doi: 10.13224/j.cnki.jasp.2021.01.018
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The qualification test risk of binomial equipment was investigated by Bayes theory to assess the performance index and establish qualification test scheme. The Beta distribution was chosen as prior distribution. The expressions of average risk and posterior risk were given. The research ideas and applications of two kinds of risk were explained. On this basis, the max posterior risk model was developed through investigating the result of qualification test. The max. posterior risk’s properties were given. Compared with posterior risk and classical risk, it demonstrated the conservation and feasibility of max. posterior risk. So the consumer benefit was protected. The test statistics scheme based on max. posterior risk conformed to the engineering rule. The test number decreased by 18%-63%, compared with test statistics scheme based on classical risk. It also analyzed the number relation between three kinds of risk and prior information, interval estimation. The properties of max. posterior risk were demonstrated, showing its wide application.
Response mechanism of thin-walled casing support system under periodic rubbing exciation
HAN Jinchang, ZUO Yanfei, FENG Kun
2021, 36(1): 167-175. doi: 10.13224/j.cnki.jasp.2021.01.019
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In view of the complex dynamic response law of the engine’s thin-walled casing support system under rubbing excitation and the difficulty of character identification of rubbing fault based on the vibration signal of the casing, a numerical simulation method for the mechanism analysis of the fault characteristics was presented. An equivalent dynamic three-dimensional solid model of the thin-walled casing system was established and the rubbing excitation was simplified by equivalent mechanics. Then the periodic rubbing fault was simulated numerically with transient dynamics method. Based on analysis of the inherent characteristics of the system, the time domain and frequency domain response characteristics were studied and the rubbing fault feature was obtained. The dominant frequency of the casing displacement vibration signal was the low-order natural frequency of the system, and the dominant frequency of the acceleration vibration signal was the rub-impact excitation frequency and its multiples. The above conclusions can be used as the basis for rub-impact faults and provide references for early fault diagnosis.
Improving the computational efficiency of rotating sound source localization via compression computational grid method
WANG Jiayu, ZHANG Ce, MA Wei
2021, 36(1): 176-184. doi: 10.13224/j.cnki.jasp.2021.01.020
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In order to improve the computational efficiency of the classical time-domain rotating source identifier (ROSI) beamforming, two different compression computational grid methods were proposed: one based on conventional beamforming, namely CG2, and the other one obtained from ROSI beamforming with a little amount of sample data, namely CG4. Experimental applications showed that both compression grid methods did not affect the effectiveness of the ROSI algorithm for rotating sound source localization. ROSI beamforming with CG2 can improve the computational efficiency of the ROSI algorithm for rotating sound source localization by a factor of 1 to 2, while ROSI beamforming with CG4 can improve the computational efficiency of the ROSI algorithm for rotating sound source localization by a factor of 13 to 18. In addition, ROSI beamforming with CG4 can still accurately locate the rotating sound source even if the microphone array plane run perpendicular to the rotating sound source plane.
Design and validation of high-lift turbine nozzle guide vane profile
ZHANG Shaowen, SHI Jiancheng, LI Wei
2021, 36(1): 185-192. doi: 10.13224/j.cnki.jasp.2021.01.021
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A method for high-lift turbine blade design based on Pritchard 11 parameters method was introduced for turbine nozzle guide vane working under low entrance Mach number and typically low lift at front part of the blade. A series of high lift nozzle guide vane profile were designed and investigated using numerical calculation, and validated by linear cascade test. Results showed that the blade loading of high-lift profile was more uniform due to increase of Mach number at front part of the suction side, and the throat suction moved forward. The Mach number characteristic and attack angle characteristic showed that the highly-loaded blades generated lower total pressure loss. The pressure loss coefficient of high-lift profile was 259% lower under design condition than that of the datum profile.
Application of advanced beamforming in rotating sound source localization
ZHOU Wei, BAO Huan, YANG Mingsui, MA Wei
2021, 36(1): 193-204. doi: 10.13224/j.cnki.jasp.2021.01.022
Abstract PDF(6543KB) icon355 icon174
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Functional beamforming, compressive sensing beamforming, and orthogonal beamforming in advanced beamforming have not been widely used in rotating sound source localization. The applications of three above advanced beamforming in rotating sound source localization were studied, and compared with conventional rotating beamforming and deconvolution approach in terms of the spatial resolution, dynamic range and source power integration for the mapping of acoustic sources (DAMAS). The simulation and experiment results showed that the three advanced beamforming can be applied to the rotating sound source localization successfully, and also can significantly improve the spatial resolution and dynamic range of the rotating sound source with higher computation efficiency. The functional beamforming had a lower spatial resolution than DAMAS in the low frequency band and was prone to high source power integration error. The performance of compressive sensing beamforming was closest to DAMAS, and the spatial resolution in the low frequency band was better than DAMAS. Orthogonal beamforming was prone to generate sound source localization position error within the low frequency range, the ability of anti-interference was weak, and source power integration was lower than DAMAS.
Influences of exhaust diffuser on chamber pressure and control method for high altitude cell
DAN Zhihong, ZHANG Song, QIAN Qiumeng, ZHANG Jianping, GUO Yuying
2021, 36(1): 205-215. doi: 10.13224/j.cnki.jasp.2021.01.023
Abstract PDF(4646KB) icon477 icon190
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In order to study the influences of flow characteristics of exhaust diffuser on the rear chamber pressure control of altitude test facilities, the flow characteristics of exhaust diffuser were analyzed and the model was constructed by ANSYS191 to reveal the true physical process. When the secondary mass flow rate was 20 kg/s, the changes of the rear chamber pressure were numerically simulated under different exhaust diffuser back pressure and main flow rate, and the model of the back pressure of exhaust diffuser, main flow rate and rear chamber pressure was obtained by spline interpolation. A simulation model of the pressure control system of rear chamber of high altitude platform was established to analyze the influences of the flow characteristics of the exhaust diffuser on the pressure regulation under different regulation modes and different control methods. The results showed that the secondary flow had great influences on the primary flow, and the velocity reached maximum at the engine nozzle exit. Then the velocity decreased quickly and declined by 88% in the mixing section of exhaust diffuser. However, the pressure increased gradually to the boundary value along axial direction of exhaust diffuser. In engine transition tests, the flow characteristics of exhaust diffuser brought great disturbances to the rear chamber pressure control system, and the regulating precision and disturbance rejection of rear chamber pressure can’t be assured by linear PID controller. However, nonlinear PID control can not only reduce the influence of the exhaust diffuser flow characteristics on the pressure regulating and reject the engine flow disturbances, but also ensure that the transient response is fast, the overshoot is small and the regulation accuracy is high.
Characteristics of plug motion in dual pulse solid rocket motor
ZHANG Jiye, LI Yingkun, HAN Feng, YAN Dengchao
2021, 36(1): 216-224. doi: 10.13224/j.cnki.jasp.2021.01.024
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Taking the plug motion process of the dual pulse solid rocket motor as the research object, a cold gas impact experimental platform for the pulse separation device was built, and the motion law of the plug in the first pulse combustion chamber was obtained. The dynamic structure overset grid method was used to simulate the motion process of the plug. The flow field structure during the motion of the plug was analyzed and the formation mechanism of the plug motion law was revealed. The study results showed that for pulse separation device with one hole, the plug moved smoothly along the axial direction in the combustion chamber. As the pressure rose, the initial acceleration of the plug increased and the motion speed increased slowly. For pulse separation device with several holes, due to the interference of the hole structures and the plugs on the flow field structure in the combustion chamber, the motion process of multiple plugs in the first pulse combustion chamber was extremely complicated, presenting the phenomenon of rotation and overturning. The difference in the motion speed, posture and position of the plug gradually increased with time. A reasonable design of the hole distribution can effectively prevent the plugs from gathering at the nozzle throat.

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