《流體引起的振動》ppt課件-文庫吧
2025-04-16 06:33 本頁面
【正文】 ss frequency nor blade pass harmonics coincide with natural frequencies of the rotor or support structure. Excessive vibration can result if allowed to do so. 需要盡力避免 BPF及其倍頻與轉(zhuǎn)子或支撐結(jié)構(gòu)的固有頻率臨近，否則會引起較大的振動。 20220529 169。SKF Slide 7 [Code] SKF [Organisation] Hydraulic amp。 aerodynamic force vibration 流體動力振動的特點(diǎn) 3. A great increase in blade pass frequency will occur if welds securing diffuser vanes experience failure allowing the diffusers to shift position slightly relative to the impeller. 若導(dǎo)葉片的焊接處發(fā)生失效，使擴(kuò)壓器相對葉輪產(chǎn)生輕微位移，它會導(dǎo)致BPF頻率處的振動大幅上升； 4. A great increase in blade pass vibration will be created if a pump impeller wear ring seizes to the shaft. 若泵口輪摩擦軸，會導(dǎo)致 BPF頻率振動的大幅上升； 5. Blade pass frequency in some particular fan types is particularly sensitive to damper settings. 對有些類型的風(fēng)機(jī)，其葉片通過頻率對阻尼設(shè)置情況非常敏感。 20220529 169。SKF Slide 8 [Code] SKF [Organisation] Hydraulic amp。 aerodynamic force vibration 流體動力振動的特點(diǎn) 6. Blade Rate Frequency (BRF) has to do with the number of times and rate at which rotating and stationary vanes coincide with one another. When they do coincide, there can be a pronounced pulse due to pression of the fluid (gas or liquid) between the rotating and stationary vanes. BRF = (RPM)(Impeller Vanes)(Diffuser Vanes)/K K = Highest Common Factor of Impeller Vanes and Diffuser Vanes 葉片比頻率 (BRF)按下式計(jì)算： BRF = (轉(zhuǎn)速 )(葉輪葉片數(shù) )(導(dǎo)葉葉片數(shù) )/K 其中： K＝ 葉輪葉片數(shù)和導(dǎo)葉葉片數(shù)的最大公約數(shù) 若兩個葉片數(shù)不互質(zhì)，則會產(chǎn)生較大的 BRF頻率的振動。 20220529 169。SKF Slide 9 [Code] SKF [Organisation] Cavitation and Starvation 氣蝕與抽空 Cavitation is a mon problem with centrifugal pumps and can be quite destructive to internal pump ponents. Often, pumps subjected to continuing cavitation will have badly pitted and/or eroded impellers. In some cases, cavitation can pletely erode away impeller vanes. Cavitation most often occurs when a pump is operating with excess capacity or low suction pressure. 氣蝕是離心泵的常見問題，經(jīng)常造成泵內(nèi)部件的嚴(yán)重?fù)p壞。遭受連續(xù)氣蝕問題的泵葉輪會產(chǎn)生嚴(yán)重的點(diǎn)蝕，在一些案例中，氣蝕會徹底蠶食掉葉輪葉片。 在泵輸送量過大或入口壓力偏低條件下，泵容易產(chǎn)生氣蝕。 20220529 169。
教學(xué)課件相關(guān)推薦
鄂ICP備17016276號-1