Benchtop shock interactions: microblast mixing of laser breakdown shock waves

Area of Science:

• Fluid Dynamics
• Plasma Physics
• Laser Physics

Background:

• Micro-shock wave mixing is crucial for understanding complex fluid dynamics.
• Laboratory-scale experiments are needed to study phenomena typically observed in large-scale detonations.
• Pulsed laser systems offer a controllable method for generating shock waves.

Purpose of the Study:

• To investigate the mixing of micro-shock waves generated by simultaneous laser pulses.
• To analyze the influence of laser energy and shock origin distance on micro-shock mixing.
• To measure the pressure response of mixed shock waves and validate experimental findings with simulations.

Main Methods:

• Utilizing two focused nanosecond laser pulses fired simultaneously.
• Employing multi-flash schlieren imaging for visualizing shock wave dynamics.
• Using high-fidelity microphones to record pressure responses.
• Corroborating experimental data with numerical simulations using the BlastX code.

Main Results:

• Demonstrated the feasibility of studying micro-shock wave mixing at laboratory scales.
• Quantified the pressure response of mixed shock waves based on microphone position.
• Validated experimental observations through high-fidelity simulations.
• Established a relationship between laser parameters, shock interaction, and pressure output.

Conclusions:

• Pulsed laser systems are effective tools for simulating detonation-like phenomena.
• Optical techniques combined with laser-induced shocks provide valuable data for fluid dynamics research.
• This experimental approach serves as a scalable surrogate for large-scale detonation studies.