性能預(yù)測的關(guān)鍵是對泵內(nèi)各種損失的計(jì)算。臥式離心泵內(nèi)的水利損失主要是葉輪和蝸殼內(nèi)的損失。性能預(yù)測采用的方法可歸納為兩種：
損失模型法。通過對各部分水力損失的物理本質(zhì)及其影響因素的分析，尋求水力損失與結(jié)構(gòu)參數(shù)的關(guān)系，對流場作一定的假設(shè)、簡化，建立水力損失的計(jì)算模型。該方法的優(yōu)點(diǎn)是可以全面考慮諸如二次流、進(jìn)口回流、邊界層分離、漩渦和尾跡等各種因素的影響，對實(shí)際的性能預(yù)測有很高的實(shí)用性和準(zhǔn)確性。
數(shù)值方法，又稱為數(shù)值試驗(yàn)或計(jì)算試驗(yàn)法。目前純數(shù)值方法主要是基于計(jì)算流體力學(xué)對泵內(nèi)流場進(jìn)行數(shù)值模擬，得到泵內(nèi)流場信息，進(jìn)而計(jì)算出臥式離心泵的揚(yáng)程、功率、效率和流量之間的關(guān)系，實(shí)現(xiàn)對臥式離心泵性能的預(yù)測(圖\文www.ds128.cn/)。
中譯英：
Performance prediction is the key to pump a variety of loss calculation. Horizontal centrifugal pump water loss is the loss of impeller and volute. Performance prediction methods can be classified into two:
Loss model method. Based on the physical nature of each part hydraulic loss and analysis of its influence factors, seek hydraulic loss and the relationship between the structural parameters of flow field, make certain assumptions, a simplified, establishing the hydraulic loss calculation model. The advantage of this method is that can be considered in a comprehensive way such as two flow, inlet reverse flow, boundary layer separation, vortex and wake and the influence of various factors, the actual performance prediction is of high practicability and accuracy.
Numerical method, also known as the numerical experimental or computational experimental method. The pure numerical method is mainly based on the computational fluid dynamics numerical simulation of the flow field inside the pump, get the pump flow information, then to calculate the horizontal centrifugal pump head, power, efficiency and the relation between flow, realize the horizontal centrifugal pump performance prediction.
|
