يعرض 41 - 60 نتائج من 74,164 نتيجة بحث عن '(( significant bit increase ) OR ( significant ((gap decrease) OR (a decrease)) ))', وقت الاستعلام: 1.06s تنقيح النتائج
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    Drill rod and drill bit parameters. حسب Sheng Xue (1881781)

    منشور في 2025
    "…Key findings reveal: (1) Axial migration velocity increases significantly with rotational speed, with 0.5–1 mm fine particles accelerating by 39% to 3.9 m s<sup>-1</sup> at 100 rpm compared to static condition, though an optimal threshold exists at 150 rpm; (2) Rod rotation induces vortical flow fields, where bit geometry impedes coarse particles (>1 mm) in blade zones, while 0.5–1 mm particles migrate at velocities higher than 2–3 mm fractions under different rotational speeds; (3) Mass flow rate at the orifice doubles with speed (reaching 0.06 kg s<sup>-1</sup> at 200 rpm), while static condition reduces efficiency by 50%. …"
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