This Data Category defines the structural, hydrodynamic and hydrostatic modeling by superposition of ELEMENTS of different types, each of which has its own unique properties (a summary is given in Element Topology Data Record). An Element is defined by specifying 1, 2, 3 or 4 node numbers (defined in Data Category 1) as is appropriate to that element. Some elements also require a material and geometric group number (defined in Data Categories 3 and 4 respectively).
Data Categories 1, 3, 4 should be thought of as a table of values which are indexed by the node, material and geometric group numbers respectively, on the Element Topology Data Record.
Note also that all elements within a structure are considered to be part of a rigid framework and cannot move relative to one another. However, there is no requirement for the actual physical connections to be modeled within the Aqwa suite of programs.
Note: At this stage of the modeling (i.e. input of Data Category 2) the program does not know how many structures the user wishes to define. Therefore The Data Category Series Terminator - FINI must be used to indicate that no more structures will be input. However, if the maximum number of structures is input, the FINI data record must be omitted, as termination of the Data Category series is then mandatory.
The 32-bit version of Aqwa can accept up to 18000 elements explicitly defined in Data Category 2. Of these, 12000 may be diffracting elements. These limits are raised to 36000/24000 elements with one symmetry data record, or 72000/48000 elements with two symmetry data records. These limits are for all the elements in a complete model, not for each individual structure.
The 64-bit version of Aqwa can accept up to 40000 elements explicitly defined in Data Category 2. Of these, 30000 may be diffracting elements. These limits are raised to 80000/60000 elements with one symmetry data record, or 160000/120000 elements with two symmetry data records. These limits are for all the elements in a complete model, not for each individual structure.
Aqwa can accept up to 99 structures, each including diffracting or non-diffracting elements, but the total number of elements on all structures must not exceed the limits above. It is possible for all these structures to interact hydrodynamically.