【摘要】：固液兩相離心泵輸送的是兩相流介質(zhì),其內(nèi)部流場與性能和清水泵差距甚大,由于固相的存在,使得泵存在揚(yáng)程和效率低下,磨損嚴(yán)重等問題,導(dǎo)致兩相流泵的工作效率低,使用壽命縮短。因此,進(jìn)行固液兩相離心泵優(yōu)化設(shè)計(jì),提高其各項(xiàng)性能至關(guān)重要,意義深遠(yuǎn)。本文應(yīng)用商用ANSYS軟件,采用CFD數(shù)值模擬,對(duì)固液兩相離心泵進(jìn)行CFD模擬計(jì)算并對(duì)其葉輪進(jìn)行優(yōu)化且進(jìn)行數(shù)值模擬。本文主要工作如下:首先,對(duì)固液兩相離心泵的全流道進(jìn)行建模并劃分網(wǎng)格,對(duì)所用網(wǎng)格進(jìn)行無關(guān)性驗(yàn)證。對(duì)離心泵設(shè)定邊界條件后進(jìn)行了定常數(shù)值模擬,研究單一粒徑條件下,離心泵在不同固相體積分?jǐn)?shù)工況的流場特性。研究結(jié)果表明:離心泵的揚(yáng)程隨固相體積分?jǐn)?shù)的增加先上升后下降,其效率持續(xù)下降,葉片所受壓力逐漸增大,且壓力面較吸力面增大幅度更大。其次,對(duì)泵在單一粒徑和組合粒徑條件下的磨損和空化性能規(guī)律進(jìn)行了研究。研究結(jié)果表明:顆粒直徑和固相體積分?jǐn)?shù)是影響兩相流泵磨損和空化性能的主要參數(shù),組合粒徑下磨損程度更深,主要集中在葉輪后蓋板和葉片壓力面,單一粒徑下的磨損則集中在前蓋板和葉片吸力面出口;固相顆粒對(duì)泵空化具有一定影響,主要集中在葉輪頭部進(jìn)口。然后,對(duì)離心泵進(jìn)行葉輪改型設(shè)計(jì),改變?nèi)~片安放角和葉片包角,二者均按β曲線變化且具有關(guān)聯(lián)性,對(duì)改型前后的五種方案進(jìn)行數(shù)值模擬。研究結(jié)果表明:當(dāng)葉輪進(jìn)口安放角與進(jìn)口包角的比值過大或過小,均未有優(yōu)化效果;當(dāng)比值略小于原始方案時(shí),泵的效率達(dá)到最高,為效率最優(yōu)方案;當(dāng)比值略高于原始方案時(shí),高效率范圍最大,為高效最優(yōu)方案。最后,在定常計(jì)算的基礎(chǔ)上進(jìn)行優(yōu)化前后的三種葉輪模型的全流道非定常模擬,研究葉輪壓力脈動(dòng)特性與頻譜特性。研究結(jié)果表明:葉片安放角與葉片包角可以決定葉輪流道的寬窄,葉輪流道的寬窄影響著進(jìn)出口的壓力脈動(dòng)與振動(dòng)幅值,當(dāng)進(jìn)口安放角與包角比值略小時(shí),流暢的壓力脈動(dòng)幅值較大,而原始方案和比值較大時(shí),壓力脈動(dòng)幅值與頻譜更為均勻。所做研究為葉輪流道寬窄對(duì)壓力脈動(dòng)的影響提供了一定的研究基礎(chǔ)。
[Abstract]:The solid-liquid two-phase centrifugal pump conveys the two-phase flow medium. The internal flow field and the performance of the two-phase centrifugal pump are different greatly. Due to the existence of the solid phase, the pump has the problems of low head, low efficiency, serious wear and so on, which leads to the low working efficiency of the two-phase flow pump. The service life is shortened. Therefore, it is of great importance to optimize the design of solid-liquid two-phase centrifugal pump and improve its performance. In this paper, using commercial ANSYS software and CFD numerical simulation, the solid-liquid two-phase centrifugal pump is simulated by CFD and its impeller is optimized and numerically simulated. The main work of this paper is as follows: firstly, the whole channel of solid-liquid centrifugal pump is modeled and meshed, and the grid is verified independently. The steady numerical simulation of centrifugal pump is carried out after the boundary conditions are set, and the flow field characteristics of centrifugal pump under different solid volume fraction are studied under the condition of single particle size. The results show that the head of centrifugal pump increases at first and then decreases with the increase of solid volume fraction, the efficiency of centrifugal pump decreases continuously, the pressure on the blade increases gradually, and the pressure surface increases greatly than that of suction surface. Secondly, the wear and cavitation properties of the pump under the conditions of single particle size and combined particle size were studied. The results show that the particle diameter and solid volume fraction are the main parameters affecting the wear and cavitation performance of the two-phase flow pump, and the wear degree under the combined particle size is deeper, mainly concentrated on the pressure surface of the rear cover plate and blade of the impeller. The wear under single particle size is concentrated on the front cover plate and the outlet of suction surface of the blade. Solid particles have a certain impact on pump cavitation, mainly concentrated in the impeller head inlet. Then, the impeller design of centrifugal pump is carried out, and the vane setting angle and the blade envelope angle are changed. Both of them change according to the 尾 curve and have correlation. The five schemes before and after the modification are numerically simulated. The results show that when the ratio of the inlet angle to the inlet angle of the impeller is too large or too small, there is no optimization effect, and when the ratio is a little less than the original scheme, the efficiency of the pump reaches the highest, which is the optimal scheme. When the ratio is slightly higher than the original scheme, the range of high efficiency is the largest, and it is the most efficient and optimal scheme. Finally, the unsteady simulation of three impeller models before and after optimization is carried out on the basis of steady calculation, and the pressure fluctuation and spectrum characteristics of the impeller are studied. The results show that the blade placement angle and the blade envelope angle can determine the width and narrow of the blade channel, and the width of the blade channel affects the pressure fluctuation and vibration amplitude of the inlet and outlet, when the ratio of the inlet setting angle to the inclusion angle is a little smaller, and the width of the blade channel affects the pressure fluctuation and vibration amplitude of the inlet. The amplitude of pressure fluctuation is larger, but the amplitude and spectrum of pressure fluctuation are more uniform when the original scheme and ratio are larger. The study provides a basis for the study of the influence of blade channel width on pressure pulsation.
【學(xué)位授予單位】：西安理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TH311

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 崔寶玲;朱祖超;林勇剛;;長中短葉片復(fù)合葉輪離心泵流動(dòng)數(shù)值模擬[J];農(nóng)業(yè)機(jī)械學(xué)報(bào);2011年03期

2 典平鴿;楊孫圣;;葉輪進(jìn)口寬度對(duì)液力透平性能的影響[J];機(jī)械設(shè)計(jì)與研究;2012年02期

3 朱勇更;;葉輪尺寸參數(shù)對(duì)徑流渦輪性能特性的影響[J];國外內(nèi)燃機(jī)車;1973年07期

4 沈天耀;前向葉輪的流動(dòng)模型及其設(shè)計(jì)計(jì)算方法[J];清華大學(xué)學(xué)報(bào)(自然科學(xué)版);1980年02期

5 俞秀民;副葉輪密封的設(shè)計(jì)計(jì)算[J];潤滑與密封;1982年03期

6 施衛(wèi)東,曹衛(wèi)東,劉厚林,仇寶云,劉小龍;不同葉輪結(jié)構(gòu)型式對(duì)污水泵性能的影響[J];農(nóng)業(yè)工程學(xué)報(bào);2003年02期

7 耿少娟;聶超群;黃偉光;馮濤;劉克;;不同葉輪形式下離心泵整機(jī)非定常流場的數(shù)值研究[J];機(jī)械工程學(xué)報(bào);2006年05期

8 豐鎮(zhèn)平,徐進(jìn)峰,沈祖達(dá);向心透平葉輪進(jìn)口型線的改型分析[J];工程熱物理學(xué)報(bào);1990年01期

9 張振山;張艷偉;楊玉敏;馬s，

本文編號(hào)：2457135