本文選題：軸流泵 + 葉輪進(jìn)口�。� 參考：《揚(yáng)州大學(xué)》2011年碩士論文

【摘要】：軸流泵葉輪進(jìn)口流速分布的均勻程度反映進(jìn)水流道設(shè)計(jì)的好壞,影響水泵的性能,掌握該斷面流速分布規(guī)律為葉輪和進(jìn)水流道優(yōu)化設(shè)計(jì)提供依據(jù),驗(yàn)證泵及泵裝置數(shù)值模擬結(jié)果。本文采用LDV對(duì)長(zhǎng)直管進(jìn)水條件軸流泵葉輪進(jìn)口流場(chǎng)進(jìn)行三維測(cè)試,得到了不同工況下葉輪進(jìn)口流速分布規(guī)律,主要完成了以下工作： 1、對(duì)試驗(yàn)軸流泵裝置進(jìn)行了外特性測(cè)試,得出了裝置性能曲線,確定了小流量、設(shè)計(jì)流量、大流量等五種測(cè)試工況。2、利用校準(zhǔn)盤(pán)對(duì)LDV進(jìn)行調(diào)試和校準(zhǔn),保證LDV在空氣中測(cè)試結(jié)果的準(zhǔn)確性,對(duì)直管流速分布進(jìn)行二維LDV測(cè)試,通過(guò)流量積分值與電磁流量計(jì)實(shí)測(cè)值比較,最大誤差為-1.2%,精度比較高,驗(yàn)證了LDV通過(guò)視窗對(duì)圓管內(nèi)流速分布測(cè)試的可行性與結(jié)果的準(zhǔn)確性。3、對(duì)軸流泵葉輪進(jìn)口距葉輪中心軸向距離分別為0.12、0.22、0.32倍葉輪直徑處的徑向測(cè)線進(jìn)行了三維LDV測(cè)試。4、分析葉輪進(jìn)口軸向速度分布結(jié)果,對(duì)邊壁采用冪函數(shù)處理的速度分布進(jìn)行流量積分計(jì)算,分析比較不同測(cè)點(diǎn)布置方案,改進(jìn)了基于速度面積法泵站流量測(cè)試時(shí)測(cè)點(diǎn)布置及流量積分方法。 由三維測(cè)試結(jié)果可以得出以下結(jié)論：1、0.5Qopt～0.7Qopt工況,軸向速度有回流、切向速度外壁側(cè)不為0,方向與葉輪旋轉(zhuǎn)方向一致,徑向速度外壁側(cè)速度方向與輪轂側(cè)相反,水流流態(tài)較差；0.8Qopt～1.2Qopt工況時(shí),軸向速度分布趨于均勻,切向速度除輪轂處基本為0,無(wú)旋轉(zhuǎn),徑向速度輪轂側(cè)與外壁側(cè)方向一致,水流流態(tài)較好。2、基于速度面積法軸流泵葉輪環(huán)形進(jìn)口斷面流量測(cè)試時(shí)：測(cè)線位置宜選在距葉輪中心0.2D-0.3D范圍內(nèi)；測(cè)點(diǎn)位置,小于0.7Qopt工況時(shí),流量積分計(jì)算誤差較大,外壁面測(cè)點(diǎn)宜布置在0.95(R-R0)處；大于等于0.7Qopt工況時(shí),靠近外壁面測(cè)點(diǎn)布置在0.9(R-R0)為宜；輪轂處測(cè)點(diǎn)在0.1(R-R0)～0.2(R-R0)為宜。
[Abstract]:The uniformity of inlet velocity distribution of axial flow pump impeller reflects the quality of inlet flow channel design, which affects the performance of the pump. Mastering the velocity distribution law of the section provides the basis for the optimal design of impeller and inlet passage.Verify the results of numerical simulation of pumps and pump devices.In this paper, the inlet flow field of axial flow pump impeller is measured by LDV, and the velocity distribution of impeller inlet under different working conditions is obtained. The main work is as follows:1. The external characteristic of the test axial flow pump device is tested, the performance curve of the device is obtained, and five test conditions, I. E. small flow rate, design flow rate and large flow rate, are determined. The LDV is debugged and calibrated by the calibration panel.To ensure the accuracy of LDV test results in air, the flow velocity distribution of straight tube is measured by two-dimensional LDV. The maximum error is -1.2 and the accuracy is high by comparing the flow integral value with the measured value of electromagnetic Flowmeter.The feasibility and accuracy of the velocity distribution test in a circular tube by LDV window are verified. The radial measurement line of axial distance from the inlet of the axial flow pump impeller to the center of the impeller is 0.12 ~ 0.22 ~ 0.32 times the diameter of the impeller, respectively. Three-dimensional LDV test is carried out for the axial distance between the impeller's inlet and the impeller's center.Analysis of the axial velocity distribution at the inlet of the impeller,This paper calculates the flow integral of the velocity distribution of the side wall treated by power function, analyzes and compares the different layout schemes of measuring points, and improves the method of measuring point arrangement and flow integral in the flow test of pumping station based on the velocity area method.From the three dimensional test results, the following conclusions can be drawn: the axial velocity has circumfluence, the tangential velocity is not 0, the direction is the same as the direction of impeller rotation, and the radial velocity is opposite to the hub side, and the radial velocity is opposite to the wheel hub side.The axial velocity distribution tends to be uniform under the poor water flow condition of 0.8Qoptl 1.2Qopt, the tangential velocity except the hub is basically 0, there is no rotation, and the radial velocity wheel side is the same as the outer wall side.The water flow pattern is better. 2. When measuring the flow rate of annular inlet section of axial flow pump impeller based on the velocity area method, the measuring line should be chosen within the 0.2D-0.3D range from the center of the impeller, and when the measuring point position is smaller than the 0.7Qopt condition, the error of flow integral calculation is large.It is suggested that the measuring points on the outer wall should be arranged at 0.95U R-R0; when the working conditions are greater than 0.7Qopt, the points near the outer wall should be arranged at 0.9V R-R0; and the measuring points at the hub should be at 0.1g R-R0 / 0.2nr0).
【學(xué)位授予單位】：揚(yáng)州大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2011
【分類(lèi)號(hào)】：TH312

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前2條

1 王剛;泵站進(jìn)、出水流道優(yōu)化水力設(shè)計(jì)方法研究[D];揚(yáng)州大學(xué);2012年

2 廖銘新;軸流泵葉輪內(nèi)部三維流場(chǎng)的LDV測(cè)量[D];揚(yáng)州大學(xué);2012年

，

本文編號(hào)：1747735