Experimental investigation of nonlinear internal waves in deep water with miscible fluids

TL;DR

This paper presents laboratory experiments on nonlinear internal solitary waves in deep water with miscible fluids, validated by simulations and exact solutions, capturing large amplitude wave behavior relevant to oceanography.

Contribution

It provides new experimental data on large amplitude ISWs with diffused interfaces, including first-time measurements in a moving frame, bridging gaps in existing weakly nonlinear theories.

Findings

Experimental validation of nonlinear ISWs with diffused interfaces

First measurements in a frame moving with the waves

Relevance to deep ocean geophysical phenomena

Abstract

Laboratory experimental results are presented for nonlinear Internal Solitary Waves (ISW) propagation in deep water configuration with miscible fluids. The results are validated against direct numerical simulations and traveling wave exact solutions where the effect of the diffused interface is taken into account. The waves are generated by means of a dam break and their evolution is recorded with Laser Induced Fluorescence (LIF) and Particle Image Velocimetry (PIV). In particular, data collected in a frame moving with the waves are presented here for the first time. Our results are representative of geophysical applications in the deep ocean where weakly nonlinear theories fail to capture the characteristics of large amplitude ISWs from field observations.