本文選題：泄洪洞 + 模型試驗(yàn)��； 參考：《長(zhǎng)江科學(xué)院》2014年碩士論文

【摘要】：隨著壩工技術(shù)的發(fā)展,在高山峽谷所建的高壩,往往具有水頭高、落差大、泄洪功率大等特點(diǎn),由此可能引發(fā)的空蝕問(wèn)題日益突出。相比于優(yōu)化體型、降低過(guò)流面不平整度和抗空蝕材料的運(yùn)用,摻氣設(shè)施的設(shè)置是一種比較有效的減蝕措施。論文在廣泛調(diào)研的基礎(chǔ)上,以烏東德水電站3#泄洪洞明流段的1：30單體水工模型為背景,采用物理模型試驗(yàn)和數(shù)值模擬相結(jié)合的方法,對(duì)摻氣設(shè)施的水力特性進(jìn)行了研究,取得了以下成果： (1)通過(guò)試驗(yàn)觀測(cè)了泄洪洞明流段不設(shè)摻氣設(shè)施條件下的過(guò)流形態(tài)、沿程水面線、壓力特性和水流空化特性,在此基礎(chǔ)上擬定了三種摻氣設(shè)施方案的布置位置和體型尺寸,并進(jìn)行了摻氣減蝕設(shè)施試驗(yàn)研究。 (2)試驗(yàn)結(jié)果表明,泄洪洞明流段曲線連接段及其以下流道的斷面水流平均流速超過(guò)30m/s。底板沿程壓力整體變化平緩,但曲線連接段的底板壓力較低,水流空化數(shù)低于0.3,需采取摻氣減蝕措施進(jìn)行保護(hù)。根據(jù)測(cè)量結(jié)果,設(shè)計(jì)了三種方案的摻氣設(shè)施位置和體型尺寸,并進(jìn)行了相應(yīng)的摻氣減蝕效果驗(yàn)證試驗(yàn)研究。綜合比較三種方案的摻氣效果,推薦使用方案Ⅲ的摻氣坎為泄洪洞底部水流摻氣。 (3)在模型試驗(yàn)的基礎(chǔ)上建立泄洪洞明流段三維模型,采用六面體結(jié)構(gòu)化網(wǎng)格對(duì)整個(gè)計(jì)算區(qū)域進(jìn)行疏密有別的網(wǎng)格劃分,并以模型試驗(yàn)結(jié)果率定數(shù)值模擬的邊界條件。 (4)采用標(biāo)準(zhǔn)κ-ε模型和VOF模型及歐拉模型對(duì)泄洪洞及摻氣設(shè)施水力特性進(jìn)行了三維數(shù)值模擬計(jì)算。主要計(jì)算了自由水面、摻氣設(shè)施水力特性和空腔特性及坎后沿程渠底板中心線的摻氣濃度。計(jì)算結(jié)果表明,VOF模型和歐拉模型可以在一定程度上模擬摻氣設(shè)施水力特性和空腔形態(tài)等水力參數(shù)。總體而言,在對(duì)泄洪洞摻氣設(shè)施的數(shù)值模擬方面,歐拉模型在一定程度上比VOF模型有更好的模擬精度。 (5)利用數(shù)值模擬可提高水利設(shè)計(jì)效率和節(jié)省費(fèi)用,并為模型試驗(yàn)提供前期預(yù)測(cè)和指導(dǎo)，，同時(shí)其結(jié)果可以作為模型試驗(yàn)補(bǔ)充和完善的依據(jù)，本文所采用的數(shù)值模擬方法及研究結(jié)果可供類似工程的研究參考。
[Abstract]:With the development of dam construction technology, high dams built in high mountain canyons often have the characteristics of high water head, large drop and large flood discharge power. Compared with optimizing the shape, reducing the roughness of flow surface and the application of anti-cavitation material, the installation of aeration equipment is an effective corrosion reduction measure. On the basis of extensive investigation and research, the hydraulic characteristics of aeration facilities are studied by using the physical model test and numerical simulation under the background of 1:30 single hydraulic model in the open flow section of the flood discharge tunnel of the Udongde Hydropower Station, and the physical model test and numerical simulation are used to study the hydraulic characteristics of the aeration facility. The following results were achieved: 1) the flow patterns, water surface profile, pressure characteristics and cavitation characteristics of flow in the open flow section of flood discharge tunnel without aeration facilities are observed experimentally. On the basis of these observations, the location and size of three aeration facilities are worked out. The experimental study on the aeration corrosion reduction facility is also carried out. 2) the experimental results show that the average flow velocity of the section of the open flow section of the flood discharge tunnel is more than 30 m / s. The pressure of the bottom plate changes slowly along the course, but the bottom pressure of the curve joint section is lower and the cavitation number of the flow is less than 0.3, so it is necessary to take aeration erosion reduction measures to protect the bottom plate. According to the measurement results, the position and size of the aeration facilities were designed, and the experimental study on the effect of the aeration corrosion reduction was carried out. By comparing the aeration effect of the three schemes, it is recommended that the aerator of scheme 鈪

本文編號(hào)：1867324