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Study on Pulse Triggering Combustion Instability in a Combustion Chamber
Available online at www.sciencedirect.com
ScienceDirect Energy Procedia 61 (2014) 1130 – 1133
The 6th International Conference on Applied Energy – ICAE2014
Study on Pulse Triggering Combustion instability in a Combustion Chamber Mi Yan, Junwei Li*, Wanxing Su, Ningfei Wang School of Aerospace Engineering,Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing, 100081, China
Abstract Based on a T-burner, pulse triggering, and ‘burning surface doubled and secondary attenuation’ algorithm, different kinds of solid propellants’ oscillation combustion features in the acoustic field were studied experimentally and numerically. In the experimental part, the effectiveness of the pulse excitation modes was explored, and the combustion instability characteristic of different solid propellants was researched. In the numerical part, the difference of pressure pulse and mass release rate pulse was studied, and performance parameters of propellant, such as burning rate and flame temperature, how to effect on the pressure coupled response function was discussed. The results shown that pulse drag burning rate must be intense enough to excite pressure oscillation. The thermo-acoustic oscillation combustion mechanism in T-burner is analyzed. The uneven oxidant particle and flue mixing of composite propellant caused the mass release rate periodic variation, that respond the pressure are the main reasons of thermoacoustic coupling effect. © 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license © 2014 The Authors. Published by Elsevier Ltd. (http://creativecommons.org/licenses/by-nc-nd/3.0/). Selection and/or peer-review under responsibility of ICAE Peer-review under responsibility of the Organizing Committee of ICAE2014
Keyword: Unsteady combustion, thermo-acoustics coupling, pulse triggering, solid propellant, T-burner, damping
1. Introduction As Rayleigh criteria, when the phase difference of combustion heat pulsation and pressure pulsation are required to satisfy a certain relation, the chamber sound energy system can get the more power from combustion than dissipation one, the pressure amplitude can increase and leads to unsteady combustion[1]. For solid composite propellant, because of the uneven of oxidant particle and flue mixing, its mass release rate could be periodic variation, just as the gas phase composition could occur resonance and flame temperature would have pulsation, which could be coupling with sound pressure fluctuations[2].Therefore, researchers used the pressure coupled response function to describe the coupling relationship between propellant combustion and pressure[3].
*
Corresponding author Tel.: +86-136-1103-9679; fax: +86-010-6891-3123. E-mail address: [email protected]
1876-6102 © 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the Organizing Committee of ICAE2014 doi:10.1016/j.egypro.2014.11.1038
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Mi Yan et al. / Energy Procedia 61 (2014) 1130 – 1133
(a)
(b)
Fig. 1. Experimental setup (a) physical model of T-burner; (b) structure diagram of grain and two propellants characteristics Table 1. Experimental combustion schemes Experimental Propellants Pulse Drags Pulse Charges
Exp1 No. 1 P-C 5g
Table 2. Calculation Schemes
Exp 2 No. 1 B-P 50g
Exp 3 No. 2 B-P 50g
Calculation Excitation modes Mass rate
Cal 1 pressure pulse No.1
Cal 2 pressure pulse No.2
Cal 3 Mass_flow pulse No.1
Cal 4 Mass_flow pulse No.2
In order to get combustion-pressure coupling performance of a specific propellant, T-burner model as one of experimental methods was firstly studied by M.D. Horton[4]. Based on T-burner, the new propellants was tested by many researchers to estimate that propellant is easily or not to induced unsteady combustion[5]. Sun had proposed an improved algorithm for pressure coupled response, which was called ‘burning surface doubled and secondary attenuation’[6]. In this work, base on a T-burner, pulse triggering, two kinds of solid propellants, oscillation combustion in acoustic field were studied experimentally and numerically. In experiments, the effectiveness of the pulse excitation modes was explored, and different kinds of solid propellants’ combustion features were studied. In calculation, CFD code FLUENT6.3® was used to calculation setup, the difference of pressure pulse and mass release rate pulse was studied, and propellant properties how to effect on the pressure coupled response function was discussed. 2. Experimental and Calculation Experimental setup has been shown by Wanxing Su[7]. T-burner experiment model and grain structure are shown as Fig.1. Grains of cup shape were placed at the ends of T-burner, which can help chamber to build pressure quickly and then get a constant pressure. Two pulse drags are respectively placed at the constant pressure section and burning end to induce pressure oscillation and attenuation. Pressure sensors were closed to grains in order to record the pressure oscillation history of chamber. Two kinds of propellants were employed in this study, as Fig.1(b) shows. The experimental schemes are shown in Table1. Two ways to produce pulse, one is propellant chips(P-C), and one is black powder(B-P). In calculation, as table 2 shows, two kinds of pulse(cal 1,2 and cal 3,4) were applied, two kinds of propellants which were in table 1 were compared here too, and the mass flux rate is affected by the pressure or not is also consider in pressure oscillation calculation in each cal. The mass release rate in calculation schemes is the same with the burning rate of propellant No. 1. 13.5
1.0
Expereiment 2
ILUVWSXOVH
Pmean ------- Pc
Pressure oscillation Pressure mean
Black powder burning moment 0.50
12
12
12.0
11.5
10
0.0 8
11.0
0.25
p'(Mpa)
Pc(MPa)
No effective pressure pulse
Pmean(MPa)
0.5
9 0.00
6 -0.25
Effective pressure pulse 10.5 3.25
(a)
3.50
3.75
4.00
4.25
Time(s)
4.50
4.75
5.00
5.25
-0.5 3.0
(b)
3.3
3.6
3.9
Time(s)
4.2
6 4.5
3
-0.50 3.0
(c)
3.2
3.4
3.6
3.8
4.0
4.2
4.4
Time(s)
Fig. 2. (a)pressure history of Exp2; (b)mean and fluctuating pressure of Exp1; (c)mean and fluctuating pressure of Exp2
Pmean(Mpa)
VHFRQGIXOVH
12.5
P(Mpa)
15
0.75
14
Propellant chips burning moment
13.0
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Mi Yan et al. / Energy Procedia 61 (2014) 1130 – 1133
3. Results and discussion Pulse excitation mode is very important, which decides the success or failure of experiments. Exp2, a successful pulse triggering experiment, its pressure history was shown in Fig.2(a). Due to two pieces of pulse drags were designed in grain, there are two pulses on the curve. Divide original curve into two parts, mean pressure and fluctuating pressure. Fig.2(b) shows result of Exp1, the failure one. Fig.2(c) shows result of Exp2, the successful one. Through Fig.2, at the pulse charge burning moment, pressure of Exp1 doesn’t product an effective pulse, only a pressure rise. Exp2’s curve has a perfect pulse and pressure oscillates. That’s because the burning rate of propellant chips in Exp1 isn’t enough bigger than grain, but black powder did it. The lower limit of pulse charge burning rate will be in-depth studied in next job. Due to the amplitude of the pressure oscillation decays in accordance with an exponential way. Attenuation constants can be obtained by plotting the peak-to-peak amplitude-time curve in a logarithmictime coordinate system (Ln(p’)-t curve). Here, use the fluctuating pressure of Exp2’s second pulse as an example of data analysis, and show how to get attenuation constant. In order to rule out the impact of higher harmonic, the P’-t oscillation curve was smoothed, as Fig. 3(a) shows. Take envelope line of fluctuating pressure to get peak-to-peak amplitude (P’). Then make the Ln(p’)-t curve and linearize it, as Fig. 3(b) shows. And attenuation constant is -42.278S-1. Through this method, attenuation constants of other cases can be obtained too. Then use the ‘burning surface doubled and secondary attenuation’ algorithm[7] to calculate the value of response function. Using FFT obtain pressure vibration frequency and amplitude. All results are shown in Table 3. According to the Table 3, as a whole, amplitude and pressure attenuation constant reflected the violent degree of the thermal acoustic coupling effect. And pressure had little effect on frequency, which is dependent on the longitudinal size of T-burner and combustion temperature. Attenuation constants of experiments all are far greater than calculation, as they have the same flow field conditions, what means the propellant combustion products provide a large damping for T-burner, and oscillation pressure trends to be zero ultimately. Compare experiments results, different propellants have different thermo-acoustics coupling features, which are affected by energy density, AP particles size, uniformity coefficient and so on. All these factors are interactional, coupling, and nonlinear. And burning rate of a specific propellant could measure through combustion experiments and get the exponent burning rate formula, which can comprehensively reflect the influence of all factors on propellant combustion to a certain extent. Two propellants have different burning rate formulas and they have the same burning rate under setting pressure, which can eliminate the impact of different of average burning rate. Therefore, there is a reason to doubt burning rate respond to pressure, as the exponent burning rate formula, could be a key factor for thermo-acoustics coupling. In order to explore this problem, burning rate respond to pressure with different exponent burning rate formula was calculated, and compared as pressure coupling response function(Re), which can easily compared with the experiment results. As table 3 shows, no matter experiments and calculation, Re of propellant No.2 is bigger than No.1, which can effectively prove the burning rate respond to pressure is a key factor for thermo-acoustics coupling, and this is the same with the theory of the smaller propellant pressure index, the more stable combustion performance. We also can found the calculation result is about 1/5 of the experiment. That’s because calculation can’t consider the influence of specific combustion process, the result is less than experiment. The two group calculation results are very close means that the way of pulse has little influence on the pressure oscillation simulation. 4. Conclusion In this paper, thermo-acoustics coupling of two propellants was studied experimentally and numerically. The pressure amplitude and attenuation constant reflected the violent degree of the thermal
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Mi Yan et al. / Energy Procedia 61 (2014) 1130 – 1133
acoustic coupling.Thermo-acoustics coupling features are influenced by energy density, AP particles size, burning rate respond to pressure and so on. And the buring rate respond to pressure is a key factor for the thermo-acoustics coupling. The burning rate of pulse charge should be big enough to induced a pressure oscillation, and there should be a lower limit of it. And the pulse ways of pressure pulse or mass flow pulse have little affect on the measurement of pressure response function. 13.0 1.2
P' of experimental date P' of smoothing higher harmonic Pressure mean
1.0
-0.1
-0.3
0.8
-0.4
11.5 0.2 0.0
11.0
Pmean(Mpa)
0.4
Ln(P' Envelope)
12.0
0.6
P'(Mpa)
Ln(P' Envelope) Linear Fit of Ln(P')
-0.2
12.5
-0.2
-0.6 -0.7 -0.8 -0.9 -1.0
10.5
-0.4
-0.5
Slop=-42.276
-1.1
-0.6 8.06
8.08
8.10
8.12
8.14
8.16
8.18
8.20
10.0 8.22
Time(s)
-1.2 8.080
8.085
8.090
8.095
8.100
Time(s)
(a)
(b)
Fig. 3. Exp2 (a) mean and fluctuating pressure and the smoothed one; (b) Ln(p')-t curves after smoothing and linear Table 3. Summary of the experimental and numerical results Code Exp2 Exp3 Cal 1 Cal 2 Cal 3 Cal 4
f1˄Hz˅ 138 142 130 128 127 128
Amplitude(Mpa) 0.0939 0.1329 0.3718 0.3688 0.0923 0.1075
α1˄S-1˅ -43.77 -40.5 -5.98 -5.67 -0.75 -0.44
f2˄Hz˅ 134 133 131 133 126 128
Amplitude(Mpa) 0.0654 0.1027 0.2985 0.2775 0.0614 0.0953
α2˄S-1˅ -44.37 -42.27 -6.4 -6.49 -1.31 -1.29
Re 10.7 13.1 1.57 2.78 1.89 2.88
References [1] Rayleigh J W S. The Explanation of certain acoustical phenomena. Nature 1878;18. [2] W.S. Sun, Combustion instabilities in solid rocket motors. Beijing: Beijing Institute of Technology Press, 1987.p. 110-119. [3] J. A. Steina, etal, The Burning Meachanism of the Ammonium Perchorate Based Composite Solid Propellants. AIAA paper 68-658. [4] M.D. Horton, Use of the one-dimensional T-burner to study oscillatory combustion. AIAA Journal 1964;2:1112-1118. [5] V.A. Arkhipov, S.A Volkov, L.N. Revyagin, Experimental Study of the Acoustic Admittance of the Burning Surface of Composite Solid P ropellants, Combustion, Explosion, and Shock Waves 2011;47:193-199. [6] W.S Sun, J.Y. Hu, Y. Sui, J.M. Fang, X.W. Zhang, C.J. Xing, Improved approach for the measurement of acoustic admittance of solid propellants. Acta Armamentarii 1988;4:14-19. [7] Wanxing Su, Ningfei Wang, Junwei Li, Yandong Zhao, Mi Yan, Improved method of measuring pressure coupled response for composite solid propellants. Journal of Sound and Vibration 2014; http://dx.doi.org/10.1016/j.jsv.2013.12.003i.
Biography Name: Mi Yan(1988-) Doctor of Aerospace Propulsion Technology and EngineeringˈBeijing Institute of Technology
ScienceDirect Energy Procedia 61 (2014) 1130 – 1133
The 6th International Conference on Applied Energy – ICAE2014
Study on Pulse Triggering Combustion instability in a Combustion Chamber Mi Yan, Junwei Li*, Wanxing Su, Ningfei Wang School of Aerospace Engineering,Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing, 100081, China
Abstract Based on a T-burner, pulse triggering, and ‘burning surface doubled and secondary attenuation’ algorithm, different kinds of solid propellants’ oscillation combustion features in the acoustic field were studied experimentally and numerically. In the experimental part, the effectiveness of the pulse excitation modes was explored, and the combustion instability characteristic of different solid propellants was researched. In the numerical part, the difference of pressure pulse and mass release rate pulse was studied, and performance parameters of propellant, such as burning rate and flame temperature, how to effect on the pressure coupled response function was discussed. The results shown that pulse drag burning rate must be intense enough to excite pressure oscillation. The thermo-acoustic oscillation combustion mechanism in T-burner is analyzed. The uneven oxidant particle and flue mixing of composite propellant caused the mass release rate periodic variation, that respond the pressure are the main reasons of thermoacoustic coupling effect. © 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license © 2014 The Authors. Published by Elsevier Ltd. (http://creativecommons.org/licenses/by-nc-nd/3.0/). Selection and/or peer-review under responsibility of ICAE Peer-review under responsibility of the Organizing Committee of ICAE2014
Keyword: Unsteady combustion, thermo-acoustics coupling, pulse triggering, solid propellant, T-burner, damping
1. Introduction As Rayleigh criteria, when the phase difference of combustion heat pulsation and pressure pulsation are required to satisfy a certain relation, the chamber sound energy system can get the more power from combustion than dissipation one, the pressure amplitude can increase and leads to unsteady combustion[1]. For solid composite propellant, because of the uneven of oxidant particle and flue mixing, its mass release rate could be periodic variation, just as the gas phase composition could occur resonance and flame temperature would have pulsation, which could be coupling with sound pressure fluctuations[2].Therefore, researchers used the pressure coupled response function to describe the coupling relationship between propellant combustion and pressure[3].
*
Corresponding author Tel.: +86-136-1103-9679; fax: +86-010-6891-3123. E-mail address: [email protected]
1876-6102 © 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the Organizing Committee of ICAE2014 doi:10.1016/j.egypro.2014.11.1038
1131
Mi Yan et al. / Energy Procedia 61 (2014) 1130 – 1133
(a)
(b)
Fig. 1. Experimental setup (a) physical model of T-burner; (b) structure diagram of grain and two propellants characteristics Table 1. Experimental combustion schemes Experimental Propellants Pulse Drags Pulse Charges
Exp1 No. 1 P-C 5g
Table 2. Calculation Schemes
Exp 2 No. 1 B-P 50g
Exp 3 No. 2 B-P 50g
Calculation Excitation modes Mass rate
Cal 1 pressure pulse No.1
Cal 2 pressure pulse No.2
Cal 3 Mass_flow pulse No.1
Cal 4 Mass_flow pulse No.2
In order to get combustion-pressure coupling performance of a specific propellant, T-burner model as one of experimental methods was firstly studied by M.D. Horton[4]. Based on T-burner, the new propellants was tested by many researchers to estimate that propellant is easily or not to induced unsteady combustion[5]. Sun had proposed an improved algorithm for pressure coupled response, which was called ‘burning surface doubled and secondary attenuation’[6]. In this work, base on a T-burner, pulse triggering, two kinds of solid propellants, oscillation combustion in acoustic field were studied experimentally and numerically. In experiments, the effectiveness of the pulse excitation modes was explored, and different kinds of solid propellants’ combustion features were studied. In calculation, CFD code FLUENT6.3® was used to calculation setup, the difference of pressure pulse and mass release rate pulse was studied, and propellant properties how to effect on the pressure coupled response function was discussed. 2. Experimental and Calculation Experimental setup has been shown by Wanxing Su[7]. T-burner experiment model and grain structure are shown as Fig.1. Grains of cup shape were placed at the ends of T-burner, which can help chamber to build pressure quickly and then get a constant pressure. Two pulse drags are respectively placed at the constant pressure section and burning end to induce pressure oscillation and attenuation. Pressure sensors were closed to grains in order to record the pressure oscillation history of chamber. Two kinds of propellants were employed in this study, as Fig.1(b) shows. The experimental schemes are shown in Table1. Two ways to produce pulse, one is propellant chips(P-C), and one is black powder(B-P). In calculation, as table 2 shows, two kinds of pulse(cal 1,2 and cal 3,4) were applied, two kinds of propellants which were in table 1 were compared here too, and the mass flux rate is affected by the pressure or not is also consider in pressure oscillation calculation in each cal. The mass release rate in calculation schemes is the same with the burning rate of propellant No. 1. 13.5
1.0
Expereiment 2
ILUVWSXOVH
Pmean ------- Pc
Pressure oscillation Pressure mean
Black powder burning moment 0.50
12
12
12.0
11.5
10
0.0 8
11.0
0.25
p'(Mpa)
Pc(MPa)
No effective pressure pulse
Pmean(MPa)
0.5
9 0.00
6 -0.25
Effective pressure pulse 10.5 3.25
(a)
3.50
3.75
4.00
4.25
Time(s)
4.50
4.75
5.00
5.25
-0.5 3.0
(b)
3.3
3.6
3.9
Time(s)
4.2
6 4.5
3
-0.50 3.0
(c)
3.2
3.4
3.6
3.8
4.0
4.2
4.4
Time(s)
Fig. 2. (a)pressure history of Exp2; (b)mean and fluctuating pressure of Exp1; (c)mean and fluctuating pressure of Exp2
Pmean(Mpa)
VHFRQGIXOVH
12.5
P(Mpa)
15
0.75
14
Propellant chips burning moment
13.0
1132
Mi Yan et al. / Energy Procedia 61 (2014) 1130 – 1133
3. Results and discussion Pulse excitation mode is very important, which decides the success or failure of experiments. Exp2, a successful pulse triggering experiment, its pressure history was shown in Fig.2(a). Due to two pieces of pulse drags were designed in grain, there are two pulses on the curve. Divide original curve into two parts, mean pressure and fluctuating pressure. Fig.2(b) shows result of Exp1, the failure one. Fig.2(c) shows result of Exp2, the successful one. Through Fig.2, at the pulse charge burning moment, pressure of Exp1 doesn’t product an effective pulse, only a pressure rise. Exp2’s curve has a perfect pulse and pressure oscillates. That’s because the burning rate of propellant chips in Exp1 isn’t enough bigger than grain, but black powder did it. The lower limit of pulse charge burning rate will be in-depth studied in next job. Due to the amplitude of the pressure oscillation decays in accordance with an exponential way. Attenuation constants can be obtained by plotting the peak-to-peak amplitude-time curve in a logarithmictime coordinate system (Ln(p’)-t curve). Here, use the fluctuating pressure of Exp2’s second pulse as an example of data analysis, and show how to get attenuation constant. In order to rule out the impact of higher harmonic, the P’-t oscillation curve was smoothed, as Fig. 3(a) shows. Take envelope line of fluctuating pressure to get peak-to-peak amplitude (P’). Then make the Ln(p’)-t curve and linearize it, as Fig. 3(b) shows. And attenuation constant is -42.278S-1. Through this method, attenuation constants of other cases can be obtained too. Then use the ‘burning surface doubled and secondary attenuation’ algorithm[7] to calculate the value of response function. Using FFT obtain pressure vibration frequency and amplitude. All results are shown in Table 3. According to the Table 3, as a whole, amplitude and pressure attenuation constant reflected the violent degree of the thermal acoustic coupling effect. And pressure had little effect on frequency, which is dependent on the longitudinal size of T-burner and combustion temperature. Attenuation constants of experiments all are far greater than calculation, as they have the same flow field conditions, what means the propellant combustion products provide a large damping for T-burner, and oscillation pressure trends to be zero ultimately. Compare experiments results, different propellants have different thermo-acoustics coupling features, which are affected by energy density, AP particles size, uniformity coefficient and so on. All these factors are interactional, coupling, and nonlinear. And burning rate of a specific propellant could measure through combustion experiments and get the exponent burning rate formula, which can comprehensively reflect the influence of all factors on propellant combustion to a certain extent. Two propellants have different burning rate formulas and they have the same burning rate under setting pressure, which can eliminate the impact of different of average burning rate. Therefore, there is a reason to doubt burning rate respond to pressure, as the exponent burning rate formula, could be a key factor for thermo-acoustics coupling. In order to explore this problem, burning rate respond to pressure with different exponent burning rate formula was calculated, and compared as pressure coupling response function(Re), which can easily compared with the experiment results. As table 3 shows, no matter experiments and calculation, Re of propellant No.2 is bigger than No.1, which can effectively prove the burning rate respond to pressure is a key factor for thermo-acoustics coupling, and this is the same with the theory of the smaller propellant pressure index, the more stable combustion performance. We also can found the calculation result is about 1/5 of the experiment. That’s because calculation can’t consider the influence of specific combustion process, the result is less than experiment. The two group calculation results are very close means that the way of pulse has little influence on the pressure oscillation simulation. 4. Conclusion In this paper, thermo-acoustics coupling of two propellants was studied experimentally and numerically. The pressure amplitude and attenuation constant reflected the violent degree of the thermal
1133
Mi Yan et al. / Energy Procedia 61 (2014) 1130 – 1133
acoustic coupling.Thermo-acoustics coupling features are influenced by energy density, AP particles size, burning rate respond to pressure and so on. And the buring rate respond to pressure is a key factor for the thermo-acoustics coupling. The burning rate of pulse charge should be big enough to induced a pressure oscillation, and there should be a lower limit of it. And the pulse ways of pressure pulse or mass flow pulse have little affect on the measurement of pressure response function. 13.0 1.2
P' of experimental date P' of smoothing higher harmonic Pressure mean
1.0
-0.1
-0.3
0.8
-0.4
11.5 0.2 0.0
11.0
Pmean(Mpa)
0.4
Ln(P' Envelope)
12.0
0.6
P'(Mpa)
Ln(P' Envelope) Linear Fit of Ln(P')
-0.2
12.5
-0.2
-0.6 -0.7 -0.8 -0.9 -1.0
10.5
-0.4
-0.5
Slop=-42.276
-1.1
-0.6 8.06
8.08
8.10
8.12
8.14
8.16
8.18
8.20
10.0 8.22
Time(s)
-1.2 8.080
8.085
8.090
8.095
8.100
Time(s)
(a)
(b)
Fig. 3. Exp2 (a) mean and fluctuating pressure and the smoothed one; (b) Ln(p')-t curves after smoothing and linear Table 3. Summary of the experimental and numerical results Code Exp2 Exp3 Cal 1 Cal 2 Cal 3 Cal 4
f1˄Hz˅ 138 142 130 128 127 128
Amplitude(Mpa) 0.0939 0.1329 0.3718 0.3688 0.0923 0.1075
α1˄S-1˅ -43.77 -40.5 -5.98 -5.67 -0.75 -0.44
f2˄Hz˅ 134 133 131 133 126 128
Amplitude(Mpa) 0.0654 0.1027 0.2985 0.2775 0.0614 0.0953
α2˄S-1˅ -44.37 -42.27 -6.4 -6.49 -1.31 -1.29
Re 10.7 13.1 1.57 2.78 1.89 2.88
References [1] Rayleigh J W S. The Explanation of certain acoustical phenomena. Nature 1878;18. [2] W.S. Sun, Combustion instabilities in solid rocket motors. Beijing: Beijing Institute of Technology Press, 1987.p. 110-119. [3] J. A. Steina, etal, The Burning Meachanism of the Ammonium Perchorate Based Composite Solid Propellants. AIAA paper 68-658. [4] M.D. Horton, Use of the one-dimensional T-burner to study oscillatory combustion. AIAA Journal 1964;2:1112-1118. [5] V.A. Arkhipov, S.A Volkov, L.N. Revyagin, Experimental Study of the Acoustic Admittance of the Burning Surface of Composite Solid P ropellants, Combustion, Explosion, and Shock Waves 2011;47:193-199. [6] W.S Sun, J.Y. Hu, Y. Sui, J.M. Fang, X.W. Zhang, C.J. Xing, Improved approach for the measurement of acoustic admittance of solid propellants. Acta Armamentarii 1988;4:14-19. [7] Wanxing Su, Ningfei Wang, Junwei Li, Yandong Zhao, Mi Yan, Improved method of measuring pressure coupled response for composite solid propellants. Journal of Sound and Vibration 2014; http://dx.doi.org/10.1016/j.jsv.2013.12.003i.
Biography Name: Mi Yan(1988-) Doctor of Aerospace Propulsion Technology and EngineeringˈBeijing Institute of Technology