Impact and friction mechanisms and structural changes of snow and ice in snow avalanches, ice blasts and icy planetecimal impacts

雪崩、冰爆和冰冷行星撞击中雪和冰的冲击和摩擦机制以及结构变化

• 批准号: 10490003
• 负责人: MAENO Norikazu
• 金额: $ 8.7万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10490003/
• 关键词: Snow avalanche; Ice blast; Icy bodies; Impact Frictiont; Crack; Snow; Ice; Shock wave

Ice-ice friction measurements were extended to the lowest sliding velocities aimed originally in the project. For the experiment a new device of non-rotation type was constructed and installed in a cold room, which enabled us to carry out the friction experiment to the velocities of 10^<-7> to 10^<-3> m/s and normal stresses of 123 to 368 kPa. The obtained results below 10^<-4> m/s was different f rom what has been expected from the traditional adhesion shear mechanism. Based on the experiment al result a new model of adhesion shear mechanism was proposed taking account of junction growth d ue to sintering of ice asperities on the sliding surfaces.High speed impact experiments were conducted in relation to the formation mechanism of characteristic craters found on regolith layers on asteroids, Mars, and other icy bodies. Samples used are mixtures of H_2O ice, CO_2 ice and rocks, and projectiles, made of H_2O ice, metal or plastic, were impacted with a speed of 100 to 600 m/s. The project was conducted with cooperation of Prof. Leliwa-Kopystysnski of Warsaw University. Effects of electric field on ice friction were investigated.

冰-冰摩擦测量扩展到项目最初目标的最低滑动速度。在实验中，我们建造了一个新的非旋转式装置，并安装在一个冷室内，使我们能够在10^<-7> ~ 10^<-3> m/s的速度和123 ~ 368 kPa的正应力范围内进行摩擦实验。在10^<-4> m/s以下得到的结果与传统黏附剪切机制的预期结果不同。在此基础上，提出了一种考虑滑动面上冰粒烧结导致结生长的黏附剪切机理模型。在小行星、火星和其他冰体的风化层上发现了特征陨石坑，并对其形成机制进行了高速撞击实验。所使用的样品是h2o冰、CO_2冰和岩石的混合物，由h2o冰、金属或塑料制成的弹丸以100至600米/秒的速度撞击。该项目是与华沙大学的Leliwa-Kopystysnski教授合作进行的。研究了电场对冰摩擦的影响。

项目成果

Mizuno, Y., T.Mizuno: "Photon Emission from Ice during Fracture"Jpn. J. Appl. Phys.. Vol.41,No.2B. L209-L211 (2002)

Mizuno, Y., T.Mizuno：“冰断裂时的光子发射”Jpn。

Arakawa, M.: "Collisional disruption of ice by high velocity impact" Proc.31th ISAS Lunar and Planetary Symp.13-16 (1998)

Arakawa, M.：“高速撞击对冰的碰撞破坏”Proc.31th ISAS Lunar and Planetary Symp.13-16 (1998)

Takei, I., N.Maeno: "The low-frequency conductivity of snow near the melting temperature"Annals of Glaciology. 32. 14-18 (2001)

Takei, I., N.Maeno：“融化温度附近雪的低频电导率”冰川学年鉴。

K. Nishimura, J. McElwaine: "Ping-pong ball avalanche experiments"Sedimentology. Vol. 31. 135-148 (2001)

K. Nishimura、J. McElwaine：“乒乓球雪崩实验”沉积学。

Mizuno, Y., T.Mizuno: "Photon Emission from Ice during Fracture"Jpn.J.Appl.Phys.. Vol.41No.2B. L209-211 (2002)

Mizuno, Y., T.Mizuno：“断裂期间冰的光子发射”Jpn.J.Appl.Phys.. Vol.41No.2B。