Numerical Simulation on Manufacturing of Pressure Vessel for Shock Food Processing Using Explosive Forming

2016 ◽  
Author(s):  
Hirofumi Iyama ◽  
Masatoshi Nishi ◽  
Yoshikazu Higa ◽  
Ken Shimojima ◽  
Osamu Higa ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Pressure Distribution ◽  
Pressure Vessel ◽  
Food Processing ◽  
Metal Plate ◽  
Underwater Shock Wave ◽  
Deformation Velocity ◽  
Underwater Shock ◽  
Explosive Forming

The explosive forming is a characteristic forming method. An underwater shock wave is generated by underwater explosion of the explosive. A metal plate is affected high strain rate by the shock loading and is formed along a metal die. Although this method has the advantage of mirroring the shape of the die, a free forming was used in this paper. An expensive metal die is not necessary for this free forming. It is possible that a metal plate is formed with simple supporting parts. However, the forming shape is depend on the shock pressure distribution act on the metal plate. This pressure distribution is able to change by the shape of explosive, a mass of explosive and a shape of pressure vessel. On the other hand, we need the pressure vessel for food processing by the underwater shock wave. Therefore, we propose making the pressure vessel by the explosive forming. One design suggestion of pressure vessel made of stainless steel was considered. However, we cannot decide suitable conditions, the mass of the explosive and the distance between the explosive and the metal plate to make the pressure vessel. In order to decide these conditions, we have tried the numerical simulation of this explosive forming. The basic simulation method was ALE (Arbitrary Laglangian Eulerian) method. Mie-Grümeisen EOS (equation of state), JWL EOS, Johnson-Cook constitutive equation for a material model were applied in the numerical simulation. In this paper, the underwater pressure contours to clear the propagations of the underwater shock wave, forming processes and deformation velocity of the metal plate is shown and it will be discussed about those results.

Study on the Effects of Shock Wave Propagation on Explosive Forming

2013 ◽  
Vol 767 ◽  
pp. 132-137
Author(s):  
Hirofumi Iyama ◽  
Yoshikazu Higa ◽  
Shigeru Itoh
Keyword(s):  
Shock Wave ◽  
Pressure Vessel ◽  
Pressure Pulse ◽  
Metal Plate ◽  
Water Medium ◽  
Underwater Shock Wave ◽  
Pressure Transmission ◽  
Underwater Shock ◽  
Explosive Forming ◽  
Primary Shock

Explosive forming is one of the unconventional techniques, in which, most commonly, the water is used as the pressure transmission medium. The explosive is set at the top of the pressure vessel filled with water, and is detonated by an electric detonator. The underwater shock wave propagates through the water medium and impinges on the metal plate, which in turn, deforms. There is another pressure pulse acting on the metal plate as the secondary by product of the expansion of the gas generated by detonation of explosive. The secondary pressure pulse duration is longer and the peak pressure is lower than the primary shock pressure. However, the intensity of these pressure pulse is based also on the conditions of a pressure vessel. In order to understand the effects of the configuration of the pressure vessel on the deformation of a metal plate, numerical simulation was performed. This paper reports those results.

Influence of Pressure Vessel Shape on Explosive Forming

2018 ◽  
Author(s):  
Hirofumi Iyama ◽  
Masatoshi Nishi ◽  
Yoshikazu Higa
Keyword(s):  
Shock Wave ◽  
Pressure Vessel ◽  
Underwater Explosion ◽  
Metal Plate ◽  
Reflected Shock Wave ◽  
Underwater Shock Wave ◽  
Reflected Shock ◽  
Final Deformation ◽  
Underwater Shock ◽  
Explosive Forming

The explosive forming is a characteristic forming method. This technique is a metal forming using an underwater shock wave. The underwater shock wave is generated by underwater explosion of the explosive. The metal plate is formed with involving the high strain rate on this technique. In generally, the pressure vessel is used in this method due to the effective utilization of the explosion energy. The underwater shock wave is propagated in water and reflected on inside wall of the pressure vessel. This reflected shock wave is affected on the deformation shape of a metal plate. Therefore, the inside shape of pressure vessel is often changed. In other words, the shape of pressure vessel is changed, the shock pressure distribution on the metal plate and it is possible that final deformation shape of the metal plate is changed. Some numerical simulations and experiments have been carried out to clear the influence of the inside shape of pressure vessel in the explosive forming. This paper is included the results and discussions on the numerical simulation and experiment used those conditions.

Numerical Simulation of Eccentric Explosive Forming Using Cylindrical Pressure Vessel

2012 ◽  
Author(s):  
Hirofumi Iyama ◽  
Shigeru Itoh
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Metal Forming ◽  
Metal Plate ◽  
Forming Process ◽  
Underwater Shock Wave ◽  
Metal Forming Process ◽  
Underwater Shock ◽  
Explosive Forming ◽  
Free Metal

Explosive forming is one of the effective metal forming methods using underwater shock wave generated by the detonation of an explosive. The experiment of eccentric spherical free metal forming by this method was carried out. This free metal forming process does not use require expensive metal die. We used simple metal die with only circular edges and considered the metal plate formed to required shape using this method. It was possible to change the pressure distribution applied on the metal plate by changing the set-up position of the explosive and the shape of the device. We have considered this method to cause lessen cost in the small production by various types of metal forming process. In this paper, we introduce the method of eccentric spherical free metal forming using underwater shock wave and present the experimental results. The numerical simulation on this method by FDM (Finite Difference Method) was carried out. In this paper, those results are discussed.

Deformation Mechanism of Metal Plate on Explosive Forming

2005 ◽  
Author(s):  
Hirofumi Iyama ◽  
Takeshi Hinata ◽  
Shigeru Itoh
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
High Speed ◽  
Underwater Explosion ◽  
Metal Plate ◽  
Sufficient Accuracy ◽  
Underwater Shock Wave ◽  
Underwater Shock ◽  
Explosive Forming ◽  
Forming Methods

The explosive forming is one of the forming methods of a metal plate performed since the 1950s. This method is different from usual static press forming. The metal plate is accelerated by underwater shock wave, which is generated by underwater explosion of an explosive. In order to deform a metal plate in predetermined form with sufficient accuracy using this forming method, it is important to grasp the mechanism. At first, it is necessary to grasp that an underwater shock wave spreads and it collides with the metal plate. And it is also necessary to show clearly what deformation of the metal plate with high-speed. Then, we investigated about the mechanism in the numerical simulation. In this research, LS-DYNA, which is the software for shock analysis was used. Moreover, the experiment was also conducted in order to confirm whether this numerical simulation is exact.

High Pressure Vessel Made by Explosive Forming

2010 ◽  
Author(s):  
Hirofumi Iyama ◽  
Hideki Hamashima ◽  
Shigeru Itoh
Keyword(s):  
Shock Wave ◽  
High Pressure ◽  
Numerical Simulations ◽  
Pressure Vessel ◽  
Metal Plate ◽  
The Other ◽  
Underwater Shock Wave ◽  
Pressure Transmission ◽  
Underwater Shock ◽  
Explosive Forming

Explosive forming is one particular forming technique, in which, most commonly, water is used as the pressure transmission medium. In recent years, we have done the development of the method which obtains a necessary form of the metal by the control of underwater shock wave acts on the metal plate, without a metal die. On the other hand, the pressure vessel is required in various fields, but we think that the free forming using the underwater shock wave is advantageous in the production of pressure vessel of a simple spherical, ellipse, parabola shape. In this paper, we will introduce an experiment and several numerical simulations that we carried out for this technical development.

Numerical Simulation for Development of Pressure Vessel for Food Processing by Shock Loading

2006 ◽  
Author(s):  
Masahiko Otsuka ◽  
Toshiaki Watanabe ◽  
Shigeru Itoh
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Numerical Analysis ◽  
Pressure Vessel ◽  
Food Processing ◽  
Shock Loading ◽  
Underwater Explosion ◽  
Underwater Shock Wave ◽  
Reflected Wave ◽  
Underwater Shock

In this study, it has aimed at the design of the pressure vessel where an underwater shock wave is applied to food efficiently. This study aims at the desigh of a pressure vessel in which the underwater shock wave generated by the underwater explosion of detonating fuse was experimentally investigated by the optical observation and the pressure measurement. Therefore the pressure vessel is designed so that suitable pressure may apply on food. This designed vessel is evaluated by the numerical analysis that used LS-DYNA3D. The interaction of the underwater shock wave, the incident wave and the reflected wave are investigated by the numerical analysis. The agreement between the experimental results and the numerical analysis was found to be good.

Shock Wave Propagation Inside of Pressure Vessel Used for Food Processing

2012 ◽  
Author(s):  
Hirofumi Iyama ◽  
Yoshikazu Higa ◽  
Shigeru Itoh
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Wave Propagation ◽  
Pressure Vessel ◽  
Food Processing ◽  
High Explosive ◽  
Underwater Explosion ◽  
Underwater Shock Wave ◽  
Reflected Wave ◽  
Underwater Shock

In this study, it has aimed at the design of the pressure vessel for food processing using an underwater shock wave. This study aims at the design of a pressure vessel in which the underwater shock wave generated by the underwater explosion of high explosive was experimentally investigated by the optical observation and the pressure measurement. Therefore the pressure vessel is designed so that suitable pressure may apply on food. This designed vessel is evaluated by the numerical simulation. The interaction of the underwater shock wave, the incident wave and the reflected wave are investigated by the numerical simulation.

Visualization of Shock Wave Propagation Behavior of the General-Purpose Batch Processing for Pressure Vessel by Numerical Simulation

2016 ◽  
Author(s):  
Ken Shimojima ◽  
Yoshikazu Higa ◽  
Osamu Higa ◽  
Ayumi Takemoto ◽  
Shigeru Itoh ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Pressure Vessel ◽  
Food Processing ◽  
Rice Flour ◽  
General Purpose ◽  
Processing Method ◽  
Underwater Shock Wave ◽  
Citrus Junos ◽  
Institute Of Technology

Recently, National Institute of Technology, Okinawa College (ONCT) has been developing a new food processing method using underwater shock wave. The continuous-operation device was manufactured for the production of rice flour, the amount of milling flour per hour and the quality of the rice powder were evaluated. In the case of Yuzu (Citrus junos), an improved fragrance was obtained using this methods compared with other general processing method. The authors have also developed a batch-type crushing device (pressure vessel) for various food processing. However, the mechanism by which is processed using shock waves has not been clarified. Therefore, in this study, the propagation characteristics of a shock wave in the developed pressure vessel were evaluated by numerical simulation. The characteristics of processing is evaluated using shock wave and, the pressure resistance of the vessel was analyzed. In addition, food processing experiments using the developed device were performed. In which, in which “Yuzu” were crushed. Yuzu before-and-after crushing were compared, and the effect of shock wave were clarified.

Development and Improvement of the Experimental Apparatus Using the Underwater Shock Wave

2013 ◽  
Vol 767 ◽  
pp. 256-260
Author(s):  
Yukimasa Omine ◽  
Takashi Gushi ◽  
Osamu Higa ◽  
Shigeru Itoh
Keyword(s):  
Shock Wave ◽  
Pressure Vessel ◽  
Food Processing ◽  
Processing Method ◽  
Coaxial Cable ◽  
Underwater Shock Wave ◽  
Experimental Apparatus ◽  
Underwater Shock ◽  
Metal Processing ◽  
Developed Pressure

The underwater shock wave has been studied in the various fields. The application of this method can be used for a molding machining, a welding and an embossing in the metal processing [. Moreover, this processing method can be used for a pulverizing, a softening, and a sterilization in the food processing. The aim of this research is to make the rice powder using by the underwater shock wave without generating of heat [. Although the underwater shock wave is generated using an explosive, the handling of the explosive is extremely accompanied by danger. Therefore, we developed the electric discharging device made to generate the underwater shock wave. It is easier to carry on the experiment using this device than the experiment of an explosive. We developed a pressure vessel for generating the underwater shock wave in various fields. The developed pressure vessel has been improved by our research group. The pressure vessel made to generate the shock wave is manufactured from a new concept, and the coaxial cable is used for wiring of the device.

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