Estimation of the Propagation of the Impact Wave Phenomenon as a Result of a Bullet Impact in PACVD-Modified Textiles

Experiment research aiming at the anti-explosion capability of the refuge chamber is a complex work with high costs. By using finite element analysis, however, could avoid this issue and implement the simulation and analysis more effectively. Based on transient dynamics approach, numerical simulation calculation and analysis of the dynamic response of the refuge chamber under the impact caused by gas explosion are presented in this paper. The results indicate that, when the refuge cabin under specified explosion impact wave stress, the maximum stress of the cabin is 370.8MPa,which is under the ultimate strength, and the maximum impact wave deformation of the cabin is 9.43mm, which is under the maximum permissive deformation (20mm), therefore the rigidity and the strength of the cabin both meet the demands. The refuge chamber presented in this paper, which remain the integrity of the cabin and the safety of the structure under specified explosion impact, has good anti-explosion ability, and could implemmet the emergency risk avoiding effectively.

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The effect of the blocking of impact ocean waves by the crevasse-ridden ice shelf

10.5194/egusphere-egu2020-9665 ◽

2020 ◽

Author(s):

Yuri Konovalov

Keyword(s):

Band Gap ◽

Numerical Experiments ◽

Amplitude Spectrum ◽

Ocean Waves ◽

Band Gaps ◽

Elastic Model ◽

Ice Shelf ◽

Impact Wave ◽

Wide Range ◽

The Impact

The propagation of high-frequency elastic-flexural waves through an ice shelf was modeled by a full 3-D elastic model, which also takes into account sub-ice seawater flow. The sea water flow is described by the wave equation. Numerical experiments were undertaken both for an intact ice shelf free of crevasses, which has idealized rectangular geometry, and for a crevasse-ridden ice shelf. The crevasses were modeled as triangle/rectangular notches into the ice shelf. The obtained dispersion spectra (the dispersion curves describing the wavenumber/periodicity relation) are not continuous. The spectra reveal gaps that provide the transition from n-th mode to (n+1)-th mode. These gaps are observed both for an intact ice shelf free of crevasses and for a crevasse-ridden ice shelf. They are aligned with the minimums in the amplitude spectrum. That is the ice shelf essentially blocks the impact wave at this transition. However, the dispersion spectrum obtained for a crevasse-ridden ice shelf, has a qualitatively difference from that obtained for an intact ice shelf free of crevasses. Moreover, the dispersion spectrum obtained for a crevasse-ridden ice shelf reveals the band gap &#8211; the zone there no eigenmodes exist (Freed-Brown and others, 2012). The numerical experiments with the crevasse-ridden ice tongue that is 16 km in longitudinal extent, 0.8km width and 100m thick, were undertaken for a wide range of the periodicities of the incident wave: from 5 s to 250 s. The obtained dispersion spectra reveal two band gaps in this range: the first band gap at about 20 s and the second band gap at about 7 s for 1km spatial periodicity of the crevasses. The width of the band gap significantly increases when the crevasses depth increases too. Respectively, the amplitude spectra reveal significantly increasing area of periodicities/frequencies where the ice shelf blocks the impact wave.ReferencesFreed-Brown, J., Amundson, J., MacAyeal, D., & Zhang, W. (2012). Blocking a wave: Frequency band gaps in ice shelves with periodic crevasses. Annals of Glaciology, 53(60), 85-89. doi:10.3189/2012AoG60A120Konovalov, Y.V. (2019). Ice-shelf vibrations modeled by a full 3-D elastic model. Annals of Glaciology, 1-7. doi:10.1017/aog.2019.9

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Formation of the structure of powder-metallurgy coatings obtained by the impact wave method

Soviet Powder Metallurgy and Metal Ceramics ◽

10.1007/bf00813955 ◽

1986 ◽

Vol 25 (5) ◽

pp. 402-405

Author(s):

A. M. Kaunov ◽

L. N. Burminskaya ◽

V. M. Bukin ◽

I. M. Ryadinskaya

Keyword(s):

Powder Metallurgy ◽

Wave Method ◽

Impact Wave ◽

The Impact

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THE IMPACT-WAVE METHOD TO DETECT A GRIFFITH CRACK AT THE INTERFACE OF COATED MATERIALS

Piezoelectricity, Acoustic Waves and Device Applications ◽

10.1142/9789812770165_0031 ◽

2007 ◽

Author(s):

Xing-Dong ZHOU ◽

Jun CHANG ◽

Jin-Quan XU

Keyword(s):

Wave Method ◽

Griffith Crack ◽

Impact Wave ◽

Coated Materials ◽

The Impact

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Renal Tubular Damage Evaluation through Enzyme Change Monitoring after Extracorporeal Shock Wave Lithotripsy

Urologia Journal ◽

10.1177/039156039306000110 ◽

1993 ◽

Vol 60 (1) ◽

pp. 45-50

Author(s):

G. Grasso Macola ◽

G.L. Tonazzi ◽

G. Gatti ◽

S. Carpanp ◽

V. Giudice

Keyword(s):

Biological Effects ◽

Tubular Damage ◽

Single Treatment ◽

Impact Wave ◽

Extracorporeal Shock Wave ◽

Before And After ◽

Enzyme Change ◽

Electromagnetic Generator ◽

Renal Tubular ◽

The Impact

To evaluate a possible onset of “biological effects” following ESWL lithotripsy, the Authors measured urinary excretion levels of two enzymes, NAG and GGT. In fact, a rise in the levels of these enzymes is regarded as an early and sensitive sign of renal injury. Fourteen patients with no complicated renal lithiasis were selected; the enzymatic levels before and after a single treatment with Lithostar Plus, a lithotriptor supplied with an electromagnetic impact wave generator, were measured. The results show that a single treatment doesn't produce any significant variation in their excretion. These results were discussed and their significance analysed. Probably, they could be explained by the lower pressure produced in the focal area by the impact wave, due to an electromagnetic generator.

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TO THE SUBSTANTIATION OF THE IMPACT-WAVE METHOD FOR ROOF BOLTING CONTROL

Up-to-date resource- and energy- saving technologies in mining industry ◽

10.30929/2074-1537.2018.1.47-54 ◽

2018 ◽

pp. 47-54 ◽

Cited By ~ 2

Author(s):

S. Skipochka ◽

◽

V. Sergienko ◽

I. Krasovskiy ◽

◽

...

Keyword(s):

Wave Method ◽

Impact Wave ◽

Roof Bolting ◽

The Impact

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Huygens' headache

Cephalalgia ◽

10.1177/0333102415570496 ◽

2015 ◽

Vol 35 (13) ◽

pp. 1215-1219

Author(s):

Peter J Koehler

Keyword(s):

Family History ◽

Wave Phenomenon ◽

Royal Society ◽

17Th Century ◽

Christiaan Huygens ◽

Académie Des Sciences ◽

Two Generations ◽

The Impact ◽

Dutch Mathematician ◽

Pendulum Clock

Background Christiaan Huygens (1629–1695) was a Dutch mathematician, physicist, and astronomer. He became well-known as inventor of the pendulum clock and described light as a wave phenomenon. He became Fellow of the Royal Society (London) and member of the Académie des Sciences (Paris). From the correspondence with family members and famous scientists, we learn that he suffered from frequent headaches. Aim To study Huygens' 22-volume Oeuvres Complètes (1888–1950) to find letters in which his headaches are mentioned and translate pertinent sections into English. Conclusions Although a posthumous diagnosis of Huygens' headaches is somewhat hazardous, the recurrent episodes with incapacitating headache and family history over two generations are suggestive for migraine. It becomes clear that it impeded his writing, reading, and research. From the letters we get an impression of the impact of the headache upon his life and the treatments that were applied in the 17th century.

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Tire Vibration Studies: The State of the Art

Tire Science and Technology ◽

10.2346/1.2167205 ◽

1975 ◽

Vol 3 (3) ◽

pp. 196-210 ◽

Cited By ~ 11

Author(s):

G. R. Potts ◽

T. T. Csora

Keyword(s):

Wave Propagation ◽

State Of The Art ◽

Mechanical Vibration ◽

Pulsed Laser ◽

Resonant Frequencies ◽

True Nature ◽

Impact Wave ◽

Vibration Transmissibility ◽

Laser Holography ◽

The Impact

Abstract General principles of mechanical vibration enigneering are used to discuss the total tire vibration problem in terms of three necessary factors: an excitation force, a transmitter, and a receiver of the vibratory force. The present state of knowledge for each of these factors is discussed and an overall goal for reduction of vehicle vibration is formulated. Current experiments for investigating tire vibration transmissibility are described and the results presented: the first used an electrohydraulic shaker; the second used time average holography, in order to see tires, and investigated impact wave propagation in tires with double-pulsed laser holography. Results show that it is difficult to reduce tire transmissibility and to shift resonant frequencies; however, this may be accomplished by introducing small amounts of body ply crown angles in radial tires (0–20 deg). Results of the impact wave propagation tests are beginning to reveal the true nature of what happens when a tire strikes a sharp bump.

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Study on Deformation and Energy Absorption of Liquid Cabin Under Ballistic Impact

Volume 11B: Honoring Symposium for Professor Carlos Guedes Soares on Marine Technology and Ocean Engineering ◽

10.1115/omae2018-78664 ◽

2018 ◽

Author(s):

Zhang Lei ◽

Zhao Pengduo

Keyword(s):

Free Surface ◽

Energy Conversion ◽

Liquid Medium ◽

Energy Absorption ◽

High Speed ◽

Water Layer ◽

Simulation Method ◽

Absorption Model ◽

Impact Wave ◽

The Impact

Liquid cabin is the most significance part protecting the ship from damage due to high-speed fragments. In order to guide the design of liquid cabin, response regularity of the impact wave in water and the speed of projectile were studied by simulation method. The deformation and energy conversion of liquid cabin in different design were also investigated. The results show that, the existence of a liquid medium can change the energy absorption model of a cabin. The thickness of water layer put significance influence on the deformation and energy absorption model of liquid cabin. Lower the level of the water lead to the free surface truncation effect of impact wave. The asymmetry and locality of the deformation of bulkhead occur to the free surface truncation effect, but it put little effect on energy absorption of liquid cabin.

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