Modeling in the Physical Sciences

Mathematical modeling is an interdisciplinary effort requiring close collaboration between scientists inside and outside ACMD. ACMD researchers cooperate with the outside scientists to develop specific mathematical models that capture the essence of the phenomena under study. Then they analyze the model; propose and develop numerical algorithms; and produce computer programs. The resulting program is run to provide simulations that are then compared with experimental results to validate the entire process and to provide the basis for further refinements and enhancements. The end benefits are to provide cheaper, quicker, and better information than experimentation alone. This information allows the outside scientists to gain understanding or to predict behavior of a complex system, and/or to improve the performance of the system under study.

The customers for our work include our collaborating NIST scientists and engineers, and, through these collaborators, industrial scientists and engineers; other cusomers are the larger community of researchers in computational science and engineering. Our aim is to work on a spectrum of tasks, including engineering and advanced development, and both long-term and short-term research.

Highlights of this year's activities include the following.

• Computational materials science continues to be a major thrust of our efforts. Materials science is one of NIST's major areas of expertise, covering a broad range of theoretical, experimental, and computational activites. Long-term mathematical modeling tasks with applications to problems in materials science have been under way by several division staff members for a number of years; other tasks are relatively new. Notable are long-term efforts in diffuse-interface methods for modeling crystal growth, and newer efforts in modeling composite materials and liquid crystals.

• We continue to strive to broaden our efforts, and to couple more closely with industry. Notable are several efforts in modeling the manufacturing process, new work in modeling lasers for use in collision avoidance, and work in using acoustic emissions to diagnose defects in materials.