NISA/HEAT

NISA/HEAT is used extensively in estimating temperature distribution, heat flux, heat flow, etc. in steady and transient conditions under the influence of heat transfer by conduction/convection/radiation. HEAT integrates with NISA II with the following features:

• Linear and nonlinear
• Nonlinearity due to material properties and/or boundary conditions, such as temperature-dependent thermal conductivity and phase change (melting and freezing)
• Steady state and transient
• Time integration techniques (forward difference, trapezoidal, backward difference)
• Constant or variable time step conditions
• Loading and boundary conditions may be time- and/or temperature-dependent
• Radiation effects with view factor calculation
• Restarts
• Automatic submodeling in user-defined regions for more accurate stress calculations

• Temperature-dependent material properties
• Time- and temperature-dependent boundary conditions
• Convection
• Radiation
• Phase changes (melting and freezing)
• Surface radiation with view factor calculation
• Isotropic and orthotropic materials

• Concentrated heat flows
• Distributed heat flux
• Internal heat generation, node or element
• Specified nodal temperature
• Coupled temperatures
• Convection and Radiation

• Nodal temperature time history
• Temperature gradients in shells
• Temperature distribution at specified time step
• Nodal heat values