An Experimental Method to Satisfy Dynamic Similarity Requirements for Model Submarine Maneuvers

摘要

Dimensional analysis and dynamic similarity requirements show that Reynolds, Froude, and Strouhal scales are important parameters to be satisfied for free-running submarine model (FRM) maneuvering experiments so that they correctly represent full-scale behavior. The requirement that all three scales be satisfied simultaneously presents conflicting demands on the relationship between the velocity U and the characteristic length L of the model. The inability to meet these demands presents technical challenges to properly satisfy dynamic similarity for the FRM. Instead, we take a first-principles approach by considering the forces and moments acting on the vehicle and seek solutions that dynamically produce the same scaled forces and moments on the model as exist on the full-scale vehicle. Thus, this paper presents an extended dynamic similarity theory, introducing scaling formulas that have been derived from similarity solutions. These are applied to an unsteady turning maneuver of the FRM to suggest an improved experimental program. The improved approach will then dynamically satisfy the aforementioned three scaling parameters.