A New Approach to Satisfy Dynamic Similarity for Model Submarine Maneuvers

Dimensional analysis and dynamic similarity requirements show that Reynolds, Froude, and Strouhal scales are important parameters to be satisfied for free-running submarine model maneuvering tests in order 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 Radio- Controlled Model RCM maneuvering tests. 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 exit on the full scale vehicle. In this manner we dynamically satisfy the above three scaling parameters. The completion of the theory will lead to the development of a modified test procedure for and subsequent validation by free-running submarine model maneuvering experiments. Summarizing, we will develop an extended dynamic similarity theory that can be applied to the unsteady maneuvers of the RCM. We will apply the theory practically to improve the RCM test program and increase correlation with full scale data. This will provide a physical basis for deciding which improvements are better made in simulation and also enhance the model the model simulation paradigm.