Kenneth W. Childs kch@ornl.gov Heat Transfer and Fluid Flow Group, Oak Ridge National Laboratory
HEATING is a general-purpose, conduction, heat transfer program written
and maintained
by the Heat Transfer and Fluid Flow Group (HTFFG). The HTFFG staff are
experienced in the use of the code and can rapidly set up and obtain
solutions to problems for which HEATING is applicable. As developers of
HEATING, the HTFFG staff are also familiar with the internal structure of
the code and can readily modify it for special applications. In fact
HEATING has served as the basis for numerous special-purpose heat transfer
codes. The four HEATING solutions in the accompanying figure illustrates
HEATING's applicability to a wide range of heat transfer problems.HEATING is written in FORTRAN 77 and can solve steady-state and/or transiet heat condcution problems in one-, two-, or three-dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. the thermal conductivity may also be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heat-generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- and position-dependent. The boundary conditions, which may be surface-to-environment or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General graybody radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a run-time memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input.
Three steady-state solution techniques are available: point-successive-overrelaxtion iterative method with extrapolation, direct-solution (for one- or two-dimensional problems), and conjugate gradient. Transient problems may be solved using any one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure (CEP), or Levy explicit method (which for some circumstances allows a time step greater than the CEP stability criterion). The solution of the system of equations arising from the implicit techniques is accomplished by a point-successive overrelaxation iteration and includes procedures to estimate the optimum acceleration parameter.
HEATING is available through the Radiation Shielding Information Center (RSIC) at Oak Ridge National Laboratory.