This study presents the investigating of microchannels flow. It is divided into two parts, the flow characteristics of micro venturi and the performance of straight-walled and curved-walled micro nozzle/diffuser respectively. The experimental results are also compared with the simulation results whereby we can observe the flow field in micro venturi and discuss the bounder effect of micro nozzle/diffuser.

本文主要是針對微噴嘴的空氣流場進(jìn)行研究與探討欧美日韩亚洲一级在线视频，研究分為兩部分進(jìn)行日韩医生无码视频播放网站，分別是探討微文氏管的流力特性及曲面微噴嘴邊界對流力效能的影響美女专区一区二区，并將實驗結(jié)果與CFD軟體的分析結(jié)果相互比較91自拍视频国产精品，藉以觀察微文氏管內(nèi)之流場分布并探討微噴嘴較佳之流力性能国产三级片黑免费。

Comparison between the velocity distributions at the different flow rate conditions showed that increasing the flow rate was help to improving the velocity distribution. The periodic mean field on r-6 plane at different axis positions showed that the flow within the vaned diffuser, especially within the inlet region, was periodic unsteady when impeller located at the different circumferential position, just as the flow within the vaneless diffuser.

有葉擴(kuò)壓器內(nèi)平均流場的分析表明免费乱伦无码免费观看网站，在定常流動的假設(shè)下，不同流量工況下有葉擴(kuò)壓器的內(nèi)部流動也呈現(xiàn)為沿軸線向后盤方向推移流動狀況逐漸惡劣的分布規(guī)律亚洲全黄无码一级，表明二元葉片構(gòu)成的平行直壁有葉擴(kuò)壓器對軸向不均勻流動的摻混作用仍然不大a片在线播放免费网址。

On the basis of three dimensional viscous numerical simulation on the internal flow field in the vaned diffuser of a centrifugal compressor,the influence of shaper parameters on the pneumatic performance in low solidity vaned diffuser is compared.

通過對一離心壓縮機(jī)葉片擴(kuò)壓器內(nèi)部流場進(jìn)行三維粘性數(shù)值模擬，對比分析了小稠度擴(kuò)壓器的主要形狀參數(shù)對氣動性能的影響非洲亚干操射。

The results indicate: diversion shell can transform the kinetic energy of fluid into pressure energy well, and eliminate the circumferential component of fluid; the inlet incidence angle of vaned diffuser increases at the condition of O.8Q, and it results in flow separation very likely and the hydraulic loss increases; it is nearly non-impact inflow at the condition of 1.2Q, and the velocity distribution is uniform at the inlet of vaned diffuser and flow separation dose not appear.

結(jié)果表明：導(dǎo)流殼能很好地將葉輪中流出的流體的動能轉(zhuǎn)化為壓能国产视频1页，并消除速度的圓周分量；在0.8Q工況下一级黄色片www，空間導(dǎo)葉的進(jìn)口沖角增大久久久久久久国产亚洲日本，容易在空間導(dǎo)葉背面產(chǎn)生流動分離，造成水力損失增加欧美在线AⅤ视频网；在1.2Q工況下美女隐私无遮挡免费视频软件，空間導(dǎo)葉的進(jìn)口接近無沖擊入流，在進(jìn)口處流速分布較均勻村姑乱伦强奸视频细节过程中文字幕，其內(nèi)部未發(fā)生流動分離現(xiàn)象一二三级免费黄色网站。

Such as: calibrating the laser system, calibrating the measurement region and focusing the CCD camera for the diffuser passage with complex shape, selecting the best incidence angle for the laser sheet,, setting the time parameter including the time between pulses and the time between records, designing the laser system, and selecting water fog with 1～5μm diameter as seedings for PIV measurement after comparing several particles. All of the work is useful to accumulate the PIV measurement experience in turbomachinery. 2. Experimental research of the unsteady flow in diffusers The instantaneous velocity fields within the vaneless and vaned diffuser were measured by using PIV technique.

本文在國內(nèi)首次進(jìn)行PIV測量系統(tǒng)對離心風(fēng)機(jī)擴(kuò)壓器內(nèi)部非定常流動的測量，為此日韩情侣中文自拍视频网站，作者作了必要的實驗前期工作：雙諧振激光器工作特性的標(biāo)定亚洲精品国产私拍在线88；針對擴(kuò)壓器復(fù)雜的流道形狀，解決了片光源照射區(qū)域位置的標(biāo)定和CCD相機(jī)的聚焦等問題；為復(fù)雜流道形狀的擴(kuò)壓器內(nèi)部流動的PIV測量選擇了最佳片光源入射角度欧美黑粗硬大一级A；選擇了合適的PIV測量時間參數(shù)乱色欧美激惰午夜；為實現(xiàn)非定常內(nèi)流的PIV測量設(shè)計了PIV系統(tǒng)的光路布置；根據(jù)非接觸測量示蹤粒子的選取原則日韩精品网站网址在线看视频，對幾種示蹤粒子進(jìn)行了篩選色色图片综合一区，最終1～5μm的水霧粒子在本文實驗條件下獲得最佳效果。

At the same time, in the inner unsteady flow-field of vaned and vaneless diffuser, as well as gap between impeller and diffuser has been measured by PIV. The measurement plane is at z=10, 15, 20mm in axial direction from impeller shroud.

對葉輪和擴(kuò)壓器在靠蓋側(cè)人人爱人人摸人人操、跨盤蓋中間流面久久99精彩视频、靠盤側(cè)三個流面，即軸向位置分別為Z=10mm一级免费看，Z=15mm肥女人一级A片免费视频，Z=20mm三個流面上的速度場進(jìn)行了實驗研究。

Numerical calculation of the unsteady flow within turbomachinery The periodic unsteady flow within impeller/vaneless diffuser or impeller/vaned diffuser was numerical simulated in this thesis. The simulation was calculated on the CFX software flat.

離心風(fēng)機(jī)內(nèi)部非定常流動的數(shù)值模擬本文對葉輪/無葉擴(kuò)壓器和葉輪/有葉擴(kuò)壓器兩種結(jié)構(gòu)形式的離心風(fēng)機(jī)內(nèi)部流動進(jìn)行了全流場非定常流動數(shù)值模擬欧美a片不卡视频。

The the sis compares the vaneless diffuser with the vane diffuser, and indicates that the vane diffuser is propitious to improve the fan performance.

指出了斜流葉輪設(shè)置導(dǎo)向葉片擴(kuò)壓器有利于提高風(fēng)機(jī)性能97中文字幕超碰精品，因此在斜流風(fēng)機(jī)中推薦使用葉片擴(kuò)壓器。

The flowfield and performance of a centrifugal compressor was predicted and analysed, which was composed of a Krain's impeller and two types of vaneless diffuser specially: one was constant area vaneless diffuser and the other was the straight-wall. The results show that the efficiency of the straight-wall vaneless diffuser is obviously lower than that of the constant area, and a separate flow occurs nearby the exit of the centrifugal impeller with the straight-wall diffuser. However, the type of vaneless diffuser has little influence on the aerodynamics performance of the centrifugal impeller. Finally, it is suggested that the constant-area vaneless diffuser should be selected as the downstream extended area of the centrifugal impeller during the prediction for the centrifugal impeller.

對Krain葉輪后帶等面積與直壁兩種形式的無葉擴(kuò)壓器離心壓縮機(jī)內(nèi)部流場進(jìn)行了計算與分析allasiaav，結(jié)果表明：直壁型無葉擴(kuò)壓器離心壓縮機(jī)的效率低于等面積無葉擴(kuò)壓器離心壓縮機(jī)的效率特级婬片A片AAA毛片AA1；直壁型無葉擴(kuò)壓器使得葉輪出口的流動出現(xiàn)分離；擴(kuò)壓器的形式對離心葉輪的整體氣動性能影響并不大欧美性交黄色一级视频A片；在進(jìn)行離心葉輪數(shù)值研究時久久黄色視頻，葉輪后的延伸區(qū)最好采用等面積無葉擴(kuò)壓器，以盡量減小無葉擴(kuò)壓器所引起的計算誤差26uuu网址。

This is put into operation the first generation of commercial proliferation of enhanced wind turbine (DAWT: diffuser augmented wind turbine), if the developers to achieve the expected results, will lead to significant reduction in the cost of wind power.

這是投入運(yùn)行的第一代商用擴(kuò)散體增強(qiáng)型風(fēng)力機(jī)(DAWT： diffuser augmented wind turbine)97干干干，如果開發(fā)者的預(yù)期結(jié)果得以實現(xiàn)，將導(dǎo)致風(fēng)力發(fā)電成本大幅度降低亚洲区在线。