CAJ | 학술논문

利用试验研究和数值模拟的方法对压电驱动的自耦合射流激发器进行研究,通过改变激发器激励参数和几何参数探求自耦合射流的变化规律.借助于动网格技术模拟了压电驱动膜片的周期性运动,实现了自耦合射流腔体内部和外部流动的耦合计算,模拟结果获得了和试验相一致的流动现象.研究结果表明:自耦合射流沿流向中心线速度分布呈现先上升后下降的趋势,在量纲一流向距离z/b=10的地方速度达到最大值;激发器的最佳波形输入为方波,在方波信号下激发器产生的射流速度最大;自耦合射流的速度随着激发器输入电压的增大而增加,但是当电压增大到175 V后这种影响趋势变得非常微弱;激发器存在两个谐振频率,分别为340 Hz和1 kHz,最佳谐振频率为1 kHz.振幅的增大,对自耦合射流的速度提高影响显著.在条件允许下,减小腔体高度与腔体直径的比值会得到更高速度的自耦合射流.研究结果为激发器的优化设计提供了一定的理论依据.
이용시험연구화수치모의적방법대압전구동적자우합사류격발기진행연구,통과개변격발기격려삼수화궤하삼수탐구자우합사류적변화규률.차조우동망격기술모의료압전구동막편적주기성운동,실현료자우합사류강체내부화외부류동적우합계산,모의결과획득료화시험상일치적류동현상.연구결과표명:자우합사류연류향중심선속도분포정현선상승후하강적추세,재량강일류향거리z/b=10적지방속도체도최대치;격발기적최가파형수입위방파,재방파신호하격발기산생적사류속도최대;자우합사류적속도수착격발기수입전압적증대이증가,단시당전압증대도175 V후저충영향추세변득비상미약;격발기존재량개해진빈솔,분별위340 Hz화1 kHz,최가해진빈솔위1 kHz.진폭적증대,대자우합사류적속도제고영향현저.재조건윤허하,감소강체고도여강체직경적비치회득도경고속도적자우합사류.연구결과위격발기적우화설계제공료일정적이론의거.
In order to get the characteristics of flow field and the influence of some parameters of a synthetic jet,experiments and numerical simulations are performed.During the simulation,moving grid technique is used for modeling the periodic movement of the piezoelectric membrane so that the coupled computation of the field cavity and the external flow field Can be realized,the flow phenomena agree well with the experiment results.The results show that:the centerline velocity of the synthetic jet takes on up-down tendency varying with the axial distances and accelerates to a maximum at a distance of approximately 1 0 slot-widths;the best actuating signal for synthetic jet actuator is square wave,at which the velocity of the synthetic jet can achieve to the maximum;the velocity of the synthetic jet increases with the imput voltage for actuator until it achieves 1 75 V;there are two resonance frequencies for actuator of the synthetic jet,340 Hz and 1 kHz,the optimal resonance frequency is 1 kHz;The improvement of the velocity of synthetic jet is remarkably influenced by the amplitude of the actuator'S membrane.The velocity of the synthetic jet will improve if the ratio of height to diameter of the actuator is small.The results provide theoretic foundations for the experimental parameters and the optimizing design of the experimental parts.