Corner Turning with the Ignition & Growth ModelA.K. Kapila and D.W. Schwendeman, RPI

Highlights:

• Well-resolved numerical simulations (with AMR) of detonation diffraction around a corner for various 2d and axisymmetric geometries.

• Two sets of reaction rate parameters modeling LX-17 and PBX-9502 (based on previously published data).

• Early behavior shows a decoupling of shock from reaction zone locally near the corner for all cases considered.

• Detonation re-forms at later times due to lateral pressure effects, and this behavior appears to be a robust feature of the ignition & growth model.

Progress (left) and pressure (right)

2d, 90 degree corner

2d, 140 degree corner

Axisymmetric, “hockey-puck” experiment geometry

Two-dimensional, 90 degree corner

A.K. Kapila and D.W. Schwendeman Rensselaer Polytechnic Institute

Leading shock separates from the reaction zone at early times.

Reaction strengthens down-wards and laterally behind the shock.

Reaction zone ultimately reconnects with the shock at later times.

Progress

Pressure

Two-dimensional, 140 degree corner

A.K. Kapila and D.W. Schwendeman Rensselaer Polytechnic Institute

Leading shock separates from the reaction zone, reaction products roll up near corner.

Reaction strengthens down-wards and laterally behind the shock.

Re-established detonation reflects from rigid boundary.

Progress

Pressure

Axisymmetric “hockey-puck” experiment geometry

A.K. Kapila and D.W. Schwendeman Rensselaer Polytechnic Institute

The now spherical leading shock separates from the reaction zone near the corner.

Lateral compression strengthens the reaction behind the shock.

Re-established detonation reflects from rigid boundary.

Progress

Pressure

axis of symmetry

axis of symmetry