TMAP7 User Manual

The TMAP Code was written at the Idaho National Engineering and Environmental Laboratory by Brad Merrill and James Jones in the late 1980s as a tool for safety analysis of systems involving tritium. Since then it was upgraded to TMAP4 and has been used in numerous applications including experiments supporting fusion safety, predictions for advanced systems such as the International Thermonuclear Experimental Reactor (ITER), and estimates involving tritium production technologies. Its further upgrade to TMAP2000 and now to TMAP7 was accomplished in response to several needs. TMAP and TMAP4 had the capacity to deal with only a single trap for diffusing gaseous species in solid structures. TMAP7 includes up to three separate traps and up to 10 diffusing species. The original code had difficulty dealing with heteronuclear molecule formation such as HD and DT under solution-law dependent diffusion boundary conditions. That difficulty has been overcome. TMAP7 automatically generates heteronuclear molecular partial pressures when solubilities and partial pressures of the homonuclear molecular species are provided for law-dependent diffusion boundary conditions. A further sophistication is the addition of non-diffusing surface species. Atoms such as oxygen or nitrogen or formation and decay or combination of hydroxyl radicals on metal surfaces are sometimes important in reactions with diffusing hydrogen isotopes but do not themselves diffuse appreciably in the material. TMAP7 will accommodate up to 30 such surface species, allowing the user to specify relationships between those surface concentrations and partial pressures of gaseous species above the surfaces or to form them dynamically by combining diffusion species or other surface species. Additionally, TMAP7 allows the user to include a surface binding energy and an adsorption barrier energy. The code includes asymmetrical diffusion between the surface sites and regular diffusion sites in the bulk. All of the previously existing features for heat transfer, flows between enclosures, and chemical reactions within the enclosures have been retained, but the allowed problem size and complexity have been increased to take advantage of the greater memory and speed available on modern computers. One additional feature unique to TMAP7 is the addition of radioactive decay for both trapped and mobile species. Whereas earlier versions required a separate FORTRAN compiler to operate, TMAP7 is based on a publiclicense compiler, distributed with the code.