Small amplitude liquid surface sloshing process detected by optical method

A laser experimental set up to detect liquid surface sloshing wave excited by the instantaneous momentum was constructed. The sloshing parameters were determined by detecting the scattering light which is modulated by the surface sloshing wave. The analytical expressions which include the relationship between optical intensity and liquid surface sloshing wave and the expressions of the wave length as well as amplitude were derived theoretically. Optical patterns corresponding to static and sloshing liquid surface were obtained experimentally. The sloshing variation process including rising and damping was achieved. Both rising and damping processes are variable exponentially. The rising and damping coefficients and maximum amplitude as well as wavelength of the sloshing wave were also measured experimentally. The detection is nondestructive and real time.