The thesis presents some modifications to make the strip theory results meet engineering demands enough even when the oscillating frequency is relatively high 本文提出了一些針對性的改進措施,使之在短波長情況下也能給出滿足工程需要精度的結(jié)果。
The oscillating frequency is 91 hz . experimental investigation has been made on the influence of the operating parameters and structure parameters on the performance of the system 以氮氣做工質(zhì),在加熱溫度為365的情況下,獲得最大的壓比為1 . 047 ,頻率是91hz 。
( 3 ) the frequency may transit from the second harmonic oscillating frequency to the third one when the hot temperature is higher than the specific temperature and the pressure is higher than the specific pressure 在實驗中發(fā)現(xiàn),在一定的加熱溫度和工作壓力下,系統(tǒng)的自激振蕩的頻率從第二諧振頻率跳變到第三諧振頻率。
As the experiment results show , multiple reasons led to the offset of oscillating frequency , including diode ’ s nonlinear characteristic , fluctuation of electrical source voltage , traction of load impedance , change of environmental temperature and humidity and the design of circuit 實驗結(jié)果表明多種因素引起了振蕩頻率的偏移,包括二極管的非線性、電源電壓的波動、負載的牽引、環(huán)境溫度濕度變化以及電路板設(shè)計方面的因素等。
Ieee ac1 , ac2 , and st1 excitation systems are selected as examples , and their parameters are identified and optimized in order that the performance indexes of the excitation systems can meet the requirements of the standards . ( 3 ) a method based on some test signal ( test signal method ) is developed to find the dominant oscillating frequencies and dampings associated with any generator in the system 然后針對我國勵磁系統(tǒng)概況,以ieeeac1 、 ac2和st1型標準勵磁系統(tǒng)為例,對其參數(shù)進行了辨識與優(yōu)化,并對每種勵磁系統(tǒng)模型給出了一套動態(tài)性能符合國家標準的參數(shù),以供仿真計算或規(guī)劃設(shè)計使用。
Principal conclusions were drawn as the following : the non compatibility of pressure or velocity of the gas on both sides of the contact surface is the cause of the formation of shock wave ; the heating effect of reflective shock wave to driving gas during charging or exhausting process is the internal mechanism of peak oscillating effect , and all the factors that influence the formation and the running of the shock wave will influence the peak oscillating frequency , cooling effect 主要結(jié)論如下:熱分離機內(nèi)激波形成的原因是射氣瞬間接觸面兩側(cè)壓力和速度不相容;峰值振蕩效應(yīng)的內(nèi)在機制為反射激波對充氣階段的驅(qū)動氣或低溫排氣的加熱,凡是影響激波形成及運動的因素都將對峰值振蕩頻率、冷效應(yīng)及熱效應(yīng)產(chǎn)生影響;當(dāng)充、排氣時間比為0 . 1763時,最佳射流激勵頻率出現(xiàn)在高階峰值振蕩頻率上。
Third , a solid lubricant embedded 40cr - ptfe bearing and a bronze c86300 - ptfe bearing were prepared . the comparatively tribological tests were performed in an oscillating sliding tribotester . the conditions were a contact mean pressure of 80 mpa , an oscillating frequency of 0 . 13 hz and relative humidity of 選擇40cr - ptfe鑲嵌型軸承與高強銅合金c86300 - ptfe鑲嵌型軸承在nh - 100型重載擺動摩擦試驗機上進行對比摩擦試驗,試驗條件為:承載壓強80mpa 、擺動頻率為0 . 13hz以及相對濕度為( 60 3 ) % 。