On Crushing of Frozen Soil by Underwater Shock Wave

The aim of study is to confirm a new technique that can crush the frozen soil and/or ice block using underwater shock wave generated by the underwater explosion of explosive. This technique can lead to the earlier sowing, which can have the larger harvest because the duration of sunshine increases. Especially, in Hokkaido prefecture, Japan, if the sowing is carried out in April, we can expect to have 150% of harvest in the ordinary season. This technique is effective against the cold regions. For example, Korea, China, Mongolia, Russia, Norway, and Sweden, etc. At first, we carried out experiments usung a detonating fuse and ice block. The process of ice breaking was observed by means of a high-speed camera. In order to check about that influence we tried to give an actual frozen soil a shock wave.

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Promotion of Thawing Frozen Soil by Shock Wave Loading

Materials Science Forum ◽

10.4028/www.scientific.net/msf.767.205 ◽

2013 ◽

Vol 767 ◽

pp. 205-210

Author(s):

Toshiaki Watanabe ◽

Hideki Hamashima ◽

Hironori Maehara ◽

Kazuyuki Hokamoto ◽

Shigeru Itoh

Keyword(s):

Shock Wave ◽

Shock Loading ◽

Underwater Explosion ◽

Water Layer ◽

Frozen Soil ◽

Shock Wave Loading ◽

Wave Loading ◽

Underwater Shock Wave ◽

Underwater Shock ◽

A New Technique

The aim of study is to confirm a new technique that can crush the frozen soil and/or ice block using underwater shock wave generated by the underwater explosion of explosive. This technique can lead to the earlier sowing, which can have the larger harvest because the duration of sunshine increases. Especially, in Hokkaido prefecture, Japan, if the sowing is carried out in April, we can expect to have 150% of harvest in the ordinary season. This technique is effective against the cold regions, for example, Russia, Norway, and Sweden, etc. In order to check about that influence we tried to give an actual frozen soil a shock wave. We could get a result that existence of water layer serves an important role in promotion of thawing by the shock loading to the frozen soil. That role was confirmed from the result of numerical simulation.

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Basic Study for Crushing of Frozen Soil by Underwater Shock Wave

Emerging Technology in Fluids, Structures, and Fluid Structure Interactions ◽

10.1115/pvp2003-1976 ◽

2003 ◽

Cited By ~ 2

Author(s):

Toshiaki Watanabe ◽

Shigeru Itoh ◽

Toru Hamada ◽

Osamu Kiyama ◽

Yutaka Kuroyama ◽

...

Keyword(s):

Shock Wave ◽

High Speed ◽

Underwater Explosion ◽

Frozen Soil ◽

Cold Region ◽

Underwater Shock Wave ◽

Basic Study ◽

Sunshine Hours ◽

Underwater Shock ◽

A New Technique

The final aim of study is confirm a new technique that can crush frozen soil and/or ice on the farm by underwater shock wave generated underwater explosion of explosive. In the cold region, for example, North Japan, Russia, Norway, and Sweden, etc., this technique can makes carry out early sowing and having large harvest. Especially, in Hokkaido prefecture Japan, if sowing is carried out in April, we may be expected to have a 150% of harvest of ordinary season due to the total of the sunshine hours. At first, we carried out experiments, which use detonating cord and ice block for the case of shock wave that collides aslant to ice. We obtained result that strength of the ice strongly depends on existence of bubble in the ice. So, we carried out experiments, which use explosive and ice block for the case of shock wave that collides verticality to ice. And, as the first step of pressure measurement, we experimented using the plate device that can detect shock wave. The process of breaking of ice was observed by using of the high-speed camera.

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Basics of Explosive Welding Process and Some Examples Using Underwater Shock Wave

JOURNAL OF THE JAPAN WELDING SOCIETY ◽

10.2207/jjws.87.43 ◽

2018 ◽

Vol 87 (1) ◽

pp. 43-47

Author(s):

Kazuyuki HOKAMOTO

Keyword(s):

Shock Wave ◽

Explosive Welding ◽

Welding Process ◽

Underwater Shock Wave ◽

Underwater Shock

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Explosive Welding Using Underwater Shock Wave Generated by the Detonation of the Detonating Code

Materials Science Forum ◽

10.4028/www.scientific.net/msf.673.265 ◽

2011 ◽

Vol 673 ◽

pp. 265-270 ◽

Cited By ~ 3

Author(s):

Akihisa Mori ◽

Li Qun Ruan ◽

Kazumasa Shiramoto ◽

Masahiro Fujita

Keyword(s):

Shock Wave ◽

Sound Velocity ◽

Detonation Velocity ◽

Explosive Welding ◽

New Method ◽

Underwater Shock Wave ◽

Metal Plates ◽

Experimental Parameters ◽

Underwater Shock ◽

Point Velocity

Detonating code is a flexible code with an explosive core. It is used to transmit the ignition of explosives with high detonation velocity in the range of 5.5 to 7 km/s. However, it is difficult to use detonating code for the explosive welding of common metals since the horizontal point velocity usually exceeds the sound velocity. Hence, in the present work, a new method using underwater shock wave generated by the detonation of detonating code was tried. The details of the experimental parameters and the results are presented. From the results it is observed that the above technique is suitable to weld thin metal plates with relatively less explosives.

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Von Neumann reflection of underwater shock wave

Journal of Materials Processing Technology ◽

10.1016/s0924-0136(98)00253-2 ◽

1999 ◽

Vol 85 (1-3) ◽

pp. 48-51 ◽

Cited By ~ 1

Author(s):

Y Nadamitsu ◽

Z.Y Liu ◽

M Fujita ◽

S Itoh

Keyword(s):

Shock Wave ◽

Underwater Shock Wave ◽

Von Neumann ◽

Underwater Shock

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Numerical Simulation on Explosive Welding Process Using Reflected Underwater Shock Wave

Materials Science Forum ◽

10.4028/www.scientific.net/msf.566.309 ◽

2007 ◽

Vol 566 ◽

pp. 309-314

Author(s):

Kazumasa Shiramoto ◽

Masahiro Fujita ◽

Yasuhiro Ujimoto ◽

Hirofumi Iyama ◽

Shigeru Itoh

Keyword(s):

Numerical Simulation ◽

Shock Wave ◽

Explosive Welding ◽

Welding Process ◽

Underwater Shock Wave ◽

Underwater Shock ◽

Effective Use

The paper describes a numerically simulated result for the explosive welding using reflected underwater shock wave. Through the numerical simulation, the effective use of reflected underwater shock wave was clearly suggested and the method to improve the assembly was demonstrated.

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