Verification and validation of underwater models

Abstract

As computational power increases and the price of software and hardware decrease, the ability to simulate the effects of oceanic currents on the performance of electronic and electroacoustic systems becomes more achievable. While the modeling of underwater effects will always be orders of magnitude more complex than atmospheric modeling, the increase in technology is causing more underwater models and simulations (M&S) to appear in the literature and on the shelf. As a result, the issue of the "credibility" of these models is taking on new meaning. As these models gain more use, they must undergo the verification and validation (V&V) process(es) specified by DoD. This paper presents a standard methodology for V&Ving undersea models that will document their credibility and provide the data needed for accreditation. The methodology is divided into different phases: each with a prescribed input and output, and each with documented results. ISTI has developed a methodology that has been adopted and successfully implemented by a number of different V&V programs. This methodology employs a unique use of Computer Assisted Software Engineering (CASE) tools to reverse engineer source code and produce analytical outputs (flow charts and tables) that aid the engineer/analyst in the V&V process. We have found that the use of CASE tools saves time, which equates to improvements in schedule, cost, and provides the subject matter expert far superior information to evaluate the model and/or simulation. This paper will describe the ISTI-developed methodology and how CASE tools are used in its support. Case studies will be discussed.