發(fā)布時間：2018-05-30 03:14

  本文選題：傾斜孔洞流 + 休止角　； 參考：《西北師范大學》2016年碩士論文

【摘要】：就顆粒體系而言,休止角是反應體系內(nèi)部力學關系的重要物理參量,對研究顆粒體系的流動性和坡面穩(wěn)定性有著重要的參考價值.在散體介質(zhì)力學,泥沙涌動力學以及堤壩、洲體失穩(wěn)等實際問題的研究中,休止角體現(xiàn)了十分重要的工程應用價值和科學理論意義.對于新近提出的傾斜孔洞流用于顆粒堆休止角的測量方法進行了系統(tǒng)及擴展實驗研究.系統(tǒng)測量了樣品顆粒在不同傾角的管道中,受重力作用通過不同尺寸孔洞的卸載流量.驗證流量Q與傾角的余弦值cosθ以及臨界流量休止角θc與粒徑-孔徑(d/D)的良好線性關系.由此得到在大孔徑極限情況下θc的線性外推角θc∞≡θc(D→∞)我們將此角與直接測量流量停止的傾斜角θs∞,樣品顆粒在光滑表面自然堆積的休止角θr,和通過直剪實驗測得的樣品內(nèi)摩擦角φ進行了比較,發(fā)現(xiàn)θc∞,θs∞,θr,φ的值能很好的吻合.本文實驗研究傾斜孔洞流流量外插法測量休止傾角與現(xiàn)有方法的比較,認為此方法能很好的排除人為測量誤差,較精確的測量休止傾角.
[Abstract]:As far as the particle system is concerned, the angle of repose is an important physical parameter of the mechanical relationship within the reaction system, which has important reference value for the study of the fluidity and slope stability of the particle system. The angle of repose reflects the very important engineering application value and the scientific theoretical significance in the study of bulk medium mechanics, sediment surge dynamics, dyke and bar instability and so on. The newly proposed method for measuring the angle of repose of particles by slanting hole flow is studied systematically and experimentally. The unloading flow rate of sample particles through different sizes of holes in pipes with different inclination angles was systematically measured under the influence of gravity. The good linear relationship between the cosine value of flow Q and dip angle cos 胃 and the critical flow angle of repose 胃 c and the particle size-aperture d / D) is verified. The linear extrapolation angle of 胃 c is obtained in the case of large aperture limit. The angle of repose 胃 r, which is deposited naturally on the smooth surface, is compared with the friction angle 蠁 measured by direct shear test. It is found that the values of 胃 c 鈭，

本文編號：1953667