DYNAMICS OF WATER DYNAMICS OF WATER CAVITY GENERATIONCAVITY GENERATION

BY PROJECTILESBY PROJECTILESAND EXPLOSIONS AND EXPLOSIONS

LA-UR-02-832LA-UR-02-832

Charles L. Mader Charles L. Mader

Michael GittingsMichael Gittings

Water Wave Amplitude as Function of HE Charge DepthWater Wave Amplitude as Function of HE Charge Depth

Upper Critical

Upper Critical

Lower Critical

PHERMEX Radiographs of aPHERMEX Radiographs of a One Inch Dia PBX-9404 Sphere Center Initiated One Inch Dia PBX-9404 Sphere Center Initiated

Detonated Half Submerged in WaterDetonated Half Submerged in Water

15 microsec

25 microsec

60 microsec

STATIC

WATER

AIR

AIR

HE

Movie available on NMWW DVD

1.0 atms Air Pressure1.0 atms Air Pressure

130 mm Air Pressure130 mm Air Pressure

16 mm Air Pressure16 mm Air Pressure

1 atms Air Pressure1 atms Air Pressure

16 mm Air Pressure16 mm Air Pressure

Kendriskii Exploding Bridge Wire Kendriskii Exploding Bridge Wire Experiments in One AtmosphereExperiments in One Atmosphere

Air.Air.

Exploding Bridgewire at 1.0 atmsExploding Bridgewire at 1.0 atms

Kendriskii Exploding Bridge Wire Kendriskii Exploding Bridge Wire Experiments in ~0.2 AtmosphereExperiments in ~0.2 Atmosphere

Air.Air.

Exploding Bridgewire at 0.2 atmsExploding Bridgewire at 0.2 atms

Exploding Bridgewire at 0.2 atmsExploding Bridgewire at 0.2 atms

CRESTONE CRESTONE NOBEL NOBEL CODE CODE

AMR EULERIANAMR EULERIANREACTIVE HYDRODYNAMICSREACTIVE HYDRODYNAMICS

0.25 cm dia PBX-9404 sphere0.25 cm dia PBX-9404 sphereDetonated Half SubmergedDetonated Half Submerged

in Water in One Atmosphere Air.in Water in One Atmosphere Air.

| 100 cm |

0 sec 25 millisec 75 millisec 275 millisec

0.25 cm dia Al sphere colliding0.25 cm dia Al sphere collidingwith water at 2 km/secwith water at 2 km/sec

in 0.1 Atmosphere in 0.1 Atmosphere

0 sec 5 millisec 20 millisec 50 millisec

| 100 cm |

0.25 cm dia Al sphere colliding0.25 cm dia Al sphere collidingwith water at 2 km/secwith water at 2 km/sec

in 5 Atmosphere Airin 5 Atmosphere Air

0 sec 5 millisec 15 millisec 30 millisec 70 millisec

| 100 cm |

0.25 cm dia Al sphere colliding0.25 cm dia Al sphere collidingwith water at 2 km/secwith water at 2 km/sec

In 1 Atmosphere AirIn 1 Atmosphere Air

0 sec 25 millisec 75 millisec 125 millisec

| 100 cm |

The difference in pressure outside The difference in pressure outside the ejecta plume above the water the ejecta plume above the water

cavity and the decreasing pressure cavity and the decreasing pressure inside the water plume as it inside the water plume as it

expands results in the ejecta plume expands results in the ejecta plume converging and colliding at the axis converging and colliding at the axis

forming a jet above and back intoforming a jet above and back intothe bubble cavity which penetrates the bubble cavity which penetrates

bottom of the cavity and formsbottom of the cavity and formsthe stem observed experimentally.the stem observed experimentally.

As the atmospheric pressureAs the atmospheric pressureis reduced the pressure inside the is reduced the pressure inside the

expanding cavity is never expanding cavity is never less than the pressure outsideless than the pressure outside

the ejecta plume.the ejecta plume.No jet or stem is generatedNo jet or stem is generated

while the cavity is expanding.while the cavity is expanding.

SummarySummary

The Nobel Code can describeThe Nobel Code can describethe experimental observedthe experimental observedfeatures of Projectile andfeatures of Projectile and

Explosion interaction with theExplosion interaction with theOcean and the resultingOcean and the resulting

generation of Tsunami Wavesgeneration of Tsunami Waves

DYNAMICS OF WATER CAVITY

GENERATION

Charles L. Mader, Michael L. Gittings

Science of Tsunami Hazards

Vol 21, pages 91-118(2003)

TWO- AND THREE-DIMENSIONAL

SIMULATIONS OF ASTEROID

OCEAN IMPACT

Galen Gisler, Robert Weaver,

Charles Mader, Michael Gittings

Science of Tsunami Hazards

Vol 21, pages 119-134(2003)