This series of books focuses on the internal wave hydrodynamic effects on submersibles. As the first book in the series, it specifically studies the patterns and mechanisms of interaction between internal waves and submersibles. Internal waves are widely-present in the stratified ocean and are a type of nonlinear, large-amplitude wave phenomenon. Submersibles are highly likely to encounter internal waves during underwater operations, which can severely affect the stability and hydrodynamic load characteristics of the submersibles, and may even lead to instability and loss of control. This book deeply investigates the effects of depth, wave amplitude, and speed on the motion response and load of submersibles under the action of internal waves, analyzes the impact of internal waves on the efficiency of appendages such as propellers and rudders, and carries out self-propulsion experiments for verification. This book fully reveals the patterns and mechanisms of interaction between internal waves and submersibles, and can be used by researchers and students in the field of marine engineering. The methods used and the conclusions drawn are of great value to the design of underwater vehicles and the industry dealing with the effects of marine environments.