ADC	Analog-to-digital converter
BW	Bubbly water
ES	Electronic shutter
HPC	High-pressure chamber
LPC	Low-pressure chamber
PC	Personal computer
PDH	Pulsed detonation hydroramjet
SW	Shock wave
ST	Signal trigger
C	Low-frequency speed of sound in bubbly water
D	Detonation velocity
D ij	Detonation velocity at measuring segment ij
d	Bubble diameter
d 0	Initial bubble diameter
h	Height of bubbly water column
L	Distance
L d	Distance between the cross sections of the donor detonation tube branching
L ij	Distance between measuring ports i and j
L p	Penetration depth of gaseous detonation products into bubbly water
M	Mach number
P 0,HPC	Initial pressure in the HPC
P 0,LPC	Initial pressure in the LPC
T	Gas temperature
T 0	Room temperature
t 1	Time taken to detonation wave to arrive at sensor P2
t 2	Time taken to detonation wave to exit a tube
u cs	Contact surface velocity
α	Volumetric gas content
γ	Specific heat ratio
Δh	Cumulative height of gas volume
ΔP	Pressure amplitude
Δt	Time interval
Δtij	Time taken to the wave front to travel between measuring ports i and j
Δx	Distance interval
τ	Delay time