Interactions of two identical wave trains with a relative separation angle of 24°

Abstract

Interactions between two identical monochromatic wave trains with a relative separation angle of 24° were experimentally investigated in a well-designed ‘X’ configuration. Wave trains with different amplitudes and frequencies were generated. The results demonstrated that the interaction was strongly dependent on both wave amplitude and frequency. For nonbreaking and lower-frequency cases, the wave trains can approximately reestablish their initial state following the interaction. However, for larger waves, the interaction was enhanced, distorting the surfaces significantly – the wave trains were no longer two-dimensional after the encounter. During the interaction process, there was an obvious increase in wave height, reaching a maximum amplification in the middle of the interaction region that was approximately 1.55 times the initial height. Furthermore, the images captured by high-speed cameras illustrated that two wave trains entered the interaction region at the same time and then merged during the interaction process, resulting in an increase in wave amplitude. The combined wave crest was initially composed of two straight segments with a relative angle of 24° and gradually morphed into a single segment as is evident in the plan view. The wave then broke in the downstream, still within the interaction region, exhibiting a crescent pattern along the crest.