Tail buffeting at high angle of attack causes distinct fatigue problem on tail structure of twin tail fighters.In this study,a piezoelectric active control experiment of tail buffeting was performed in a wind tunnel u...Tail buffeting at high angle of attack causes distinct fatigue problem on tail structure of twin tail fighters.In this study,a piezoelectric active control experiment of tail buffeting was performed in a wind tunnel using arching PZT actuator(APA) and principal modal control(PMC) method.Test results showed the peak value of power spectral density(PSD) function of tail buffeting acceleration response could be suppressed by about 42% when the angle of attack reached 35°,indicating the validity and feasibility of PMC method and APA for tail buffeting alleviation at high angle of attack.展开更多
A dual-sided multiple fans system with a piezoelectric actuator （＂D-MFPA＂）, which is able to drive eight passive vibrating fans and provide two-directional air flows by using only one piezoelectric actuator, has b...A dual-sided multiple fans system with a piezoelectric actuator （＂D-MFPA＂）, which is able to drive eight passive vibrating fans and provide two-directional air flows by using only one piezoelectric actuator, has been investigated in this study. Moreover, two types of the fan designs, viz. magnetic fan （MF） and composite magnetic fan （CMF） were also explored. In the investigation of the MF, the results indicated that the resonance frequency of the D-MFPA increased from 27.6 Hz to 66 Hz as the length of the carbon fiber plate （L） decreased from 55 mm to 35 mm. It also decreased the amplitude of the D-MFPA from 12.4mm to 4.8 mm. For CMF, the results showed that the resonance frequency decreased when the length of the Mylar plate （Et） increased, and the maximum decrease was from 66 Hz to 45 Hz when L= 35 mm and Er= 30 mm. Dimensionless heat convection number （MD_MFPA） was defined to describe and quantify the improvement in the thermal performance. The results showed that the optimal MO-MFPA of the single piezoelectric fan was 1,58 for cooling one heat source. By contrast, under the same power consumption, the D-MFPA not only cooled two heat sources but also displayed better thermal performance.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 11072198)the Basic Research Program of Northwestern Polytechnical University (Grant No. JC201102) "111" Project(Grant No. B07050)
文摘Tail buffeting at high angle of attack causes distinct fatigue problem on tail structure of twin tail fighters.In this study,a piezoelectric active control experiment of tail buffeting was performed in a wind tunnel using arching PZT actuator(APA) and principal modal control(PMC) method.Test results showed the peak value of power spectral density(PSD) function of tail buffeting acceleration response could be suppressed by about 42% when the angle of attack reached 35°,indicating the validity and feasibility of PMC method and APA for tail buffeting alleviation at high angle of attack.
文摘A dual-sided multiple fans system with a piezoelectric actuator （＂D-MFPA＂）, which is able to drive eight passive vibrating fans and provide two-directional air flows by using only one piezoelectric actuator, has been investigated in this study. Moreover, two types of the fan designs, viz. magnetic fan （MF） and composite magnetic fan （CMF） were also explored. In the investigation of the MF, the results indicated that the resonance frequency of the D-MFPA increased from 27.6 Hz to 66 Hz as the length of the carbon fiber plate （L） decreased from 55 mm to 35 mm. It also decreased the amplitude of the D-MFPA from 12.4mm to 4.8 mm. For CMF, the results showed that the resonance frequency decreased when the length of the Mylar plate （Et） increased, and the maximum decrease was from 66 Hz to 45 Hz when L= 35 mm and Er= 30 mm. Dimensionless heat convection number （MD_MFPA） was defined to describe and quantify the improvement in the thermal performance. The results showed that the optimal MO-MFPA of the single piezoelectric fan was 1,58 for cooling one heat source. By contrast, under the same power consumption, the D-MFPA not only cooled two heat sources but also displayed better thermal performance.
