潜孔锤钻进孔口密封器流场数值模拟及优化设计

为定向收集风动潜孔锤钻进时排出的岩矿样，降低粉尘污染同时提高岩矿样采取率，对孔口密封器内流场进行了计算流体动力学分析（CFD），分别讨论了传统密封器、隔板式密封器、流线型式密封器结构形式及其相关结构参数（隔板位置L、出口直径d、出口角度θ）对密封效果的影响规律并进行优化设计。分析表明，三类密封器密封效果受结构形式和出口直径d影响最为明显:当d为40～160 mm时，隔板式和流线式密封器密封效果远好于传统密封器;当d>160 mm时，隔板式密封器与传统密封器的效果相当，而流线式密封器的效果始终是三者当中最好的。经现场试验证明，采用优化过的孔口密封器对岩矿样实施定向收集，除尘效果很好,且岩矿样平均采取率可达97%。

Numerical Simulation of Geometry Parameters for Optimization Design of Orifice Sealer Used in DTH Hammer Drilling

For the purpose of directional dust collection, improving sampling rate and reducing air pollution caused by dust during the hole drilling, computational fluid dynamics (CFD) technique is employed to investigate how the structure types of traditional orifice sealer, clapboard orifice sealer and streamline orifice sealer and their geometry parameters(clapboard location(L), outlet diameter(d) and outlet angle(θ) )influence the orifice seal effect. And optimal parameters are selected to carry out structure design of the sealer. According to the results, the seal effect of three types of sealer is obviously affected by their types and the outlet diameter(d). When d=40-160 mm, clapboard orifice sealer and streamline orifice sealer perform much better than the traditional sealer, and when d>160 mm, the performance of clapboard sealer becomes lower than the traditional sealer. However, the streamline orifice sealer always performs the best among the three of them. On-the-spot experiment shows that when using the orifice sealer, the effect of dedusting turns out to be satisfied and the average of sampling rate which can reach 97% is also acceptable.