On modeling Richtmyer-Meshkov turbulent mixing widths

Abstract We present several observations concerning the Richtmyer–Meshkovmixing widths after a shock or reshock passes through the interface between two fluids. The mixing evolves with two oppositely-moving fronts: A bubble ( b ) side into the heavier fluid and a spike ( s ) side into the lighter fluid. Our first observation concerns the reference surface used to partition the total mix width, h b + s , into separate h b and h s widths. Next, we point out that if and when h b and h s obey power-laws t θ with separate θ b and θ s , then h b + s cannot be given, except as an approximation, by a single θ b + s . Finally, we describe a fully continuous model for h i t , i = b , s , or b + s , as the solution to the “drag equation” with a time-dependent θ i ( t ) .