【摘要】：應(yīng)用氣力輸送理論,建立鉆屑顆粒群孔內(nèi)懸浮模型,推導(dǎo)鉆屑顆粒群啟動最小氣流速度求解方程,結(jié)合案例分析鉆屑顆粒直徑、摩擦系數(shù)及鉆孔傾角對鉆屑顆粒群啟動速度的影響規(guī)律。結(jié)果表明,施工俯孔時,最小啟動風(fēng)速存在極值θD,θDθ0時,伴隨鉆孔傾角θ絕對值增大,所需最小啟動風(fēng)速va逐漸增大,在θD~-π/2范圍,伴隨鉆孔傾角絕對值的增大,所需最小啟動風(fēng)速va呈現(xiàn)小幅度減小趨勢;施工仰孔時,存在角度θU,當(dāng)0θθU時,伴隨仰孔傾角逐漸增大,所需最小啟動風(fēng)速逐漸降低,當(dāng)θθU時,鉆屑在自重作用下自行滑落;摩擦系數(shù)對最小啟動風(fēng)速的影響規(guī)律與鉆孔傾角類似,當(dāng)俯孔傾角θ=-π/2時,不同摩擦系數(shù)曲線交于同一點,表明當(dāng)θ=-π/2時,最小啟動風(fēng)速與摩擦系數(shù)無關(guān)。
[Abstract]:Based on the pneumatic conveying theory, the suspension model in the hole of drill chip particle group is established, and the equation for solving the minimum airflow velocity of drill chip particle group is derived. the influence of drill chip particle diameter, friction coefficient and drilling inclination angle on the starting speed of drill chip particle group is analyzed with a case study. The results show that the minimum starting wind speed va increases gradually with the increase of the absolute value of drilling inclination angle, and the minimum starting wind speed va decreases slightly with the increase of the absolute value of drilling inclination angle when the minimum starting wind speed exists extreme value theta D, and the minimum starting wind speed va increases gradually with the increase of the absolute value of drilling inclination angle in the range of thd 鈮，

本文編號：2525612