HTAS1: a two-dimensional heat transfer analysis of fuel casks

The Heat Transfer Analysis Sequence Number One (HTAS1) control module was developed for the United States Nuclear Regulatory Commission to perform standardized thermal analyses on a class of nuclear fuel shipping containers. HTAS1, a control module in the SCALE system where SCALE is an acronym for Standardized Computer Analyses for Licensing Evaluation, uses the HEATING6 functional module to perform the prescribed thermal analysis. The nuclear fuel shipping container must be composed of acceptable combinations of zones consisting of a cavity, an inner shell shielding, an outer shell, a neutron shield, a water jacket, and impact limiters. Thermal properties for the material in each zone may be extracted from a material property library or may be supplied by the user. The desired thermal analysis of the nuclear fuel shipping container is defined by an analytical sequence composed of one or more of the following calculations chosen in an acceptable order: an initial steady state; a prefire steady state; a fire transient; a postfire transient; and a final steady state. Each calculation in an analytical sequence specifies the type (steady state or transient), the ambient temperature, the duration of any transient, and the heat transfer mechanisms at the surface of the model. Selected portions of the model may be deleted at certain points in an analytical sequence to simulate changes in the nuclear fuel shipping container during an analysis. The model and analytical sequence are described to HTAS1 using free-form, keyword-oriented data making extensive use of defaults