CAJ | 학술논문

利用数值模拟手段,在k-ε双方程模型基础上计算封闭的N-S方程,对保径块结构进行流场模拟。随着保径块螺旋角度增大,流体旋流作用加剧,保径块内流速增加明显,10～20°螺旋角度的保径块最适合PDC钻头。在常用保径长度范围内,保径块长度对PDC钻头流场影响微小。随着保径宽度增加,保径块下端涡流区域增大,保径宽度大于30°时,涡流区域急速扩张,五刀翼PDC钻头保径宽度应小于30°。
이용수치모의수단,재k-ε쌍방정모형기출상계산봉폐적N-S방정,대보경괴결구진행류장모의。수착보경괴라선각도증대,류체선류작용가극,보경괴내류속증가명현,10～20°라선각도적보경괴최괄합PDC찬두。재상용보경장도범위내,보경괴장도대PDC찬두류장영향미소。수착보경관도증가,보경괴하단와류구역증대,보경관도대우30°시,와류구역급속확장,오도익PDC찬두보경관도응소우30°。
Through numerical modeling, this paper focuses on the flow field simulation of the structure of the Gauge block in the basis of closed N-S equation calculation with κ-ε equation. Some laws are found that with the increase of Helix angle,the swirl of fluid intensifies,the velocity of fluid in Gauge block increases significantly and the most suitable helix angle for Gauge block is 10°-20°.Within common lengths of Gauge block,it affects slightly on the PDC bit flow field. With the width of Gauge block increasing ,the swirl area under Gauge block increases, when the width is greater than 30° ,the swirl region expands rapidly.A conclusion is got for Five knife wings PDC bit, and the width of gauge block should be less than 30°.