Conditional Simulation of Laboratory Waves

Abstract

A conditional simulation may be defined as a numerical method for embedding a deterministic sequence of waves or wave groups into a random wave simulation having a specified target variance spectrum. The conditional simulation may be performed in either the time or frequency domains. In the time domain, the procedure is direct and easy to understand, but it is time-consuming to compute. In the frequency domain, the procedure is more efficient when finite Fourier transform algorithms are used. The numerical stability of conditional simulation depends on the condition of a covariance matrix that depends on (1) the ratio of the length of the embedded wave sequence to the length of the unconditional sequence; (2) the compatibility of the variance of the embedded wave sequence with the variance of the target spectrum; and (3) the size of the discrete simulation time step Δ