Multiscale SimulationsThe optimal CST Studio Suite solver choice for an installed antenna placement simulation depends on a number of factors, including the electrical size of the model. The electrical size is a physical length expressed in terms of wavelengths. The table below defines the electrical size of various antenna frequencies for an aircraft 30 meters in length.
Antennas typically contain geometries that are electrically small, whereas many platform geometries are electrically large. Therefore, antenna placement simulations, which include both a platform and antennas, are multiscale problems. The CST Studio Suite hybrid solver technology allows the efficient simulation of multiscale problems. This technology couples high frequency solvers to efficiently solve problems with both electrically small and large geometries, which you cannot simulate otherwise. To couple the solvers, CST Studio Suite uses an automated workflow to decompose an assembled system into individual domains. Each subdomain can then be solved with the best suited method (for example, the transient, frequency domain, integral equation, asymptotic, or TLM solvers). Choosing a SolverThe Antenna Placement app automatically generates the master simulation project with the appropriate solvers. However, you can customize the solver choice when you configure the master simulation project. The preferred solver choice depends on the electrical size of the model. The transient solver is ideal for electrically small-to-medium size models, such as a free-standing Very High Frequency (VHF) antenna. As the electrical size of the model increases, hybrid solutions handle the simulation more efficiently. In the hybrid solution, CST Studio Suite uses the transient solver to simulate the antenna by default, while another solver simulates the electrically large aircraft. By coupling these simulations, the hybrid solution efficiently handles problems with small and large electrical sizes, reducing your simulation runtime. There are additional methods you can use when choosing a solver to reduce the simulation runtime. For example, CST Studio Suite hybrid solver technology runs the simulation using the integral equation solver and a tetrahedral surface mesh by default. If you use a complex platform geometry of medium electrical size, which cannot be easily simplified, you can consider switching from the integral equation solver to the transient equation solver in the platform project when configuring the master simulation project in CST Studio Suite. Hybrid Solver ExecutionDuring the CST Studio Suite hybrid solver execution, CST Studio Suite simulates the platform and antenna subdomains as individual simulation projects. The platform simulation project contains a field interface as a behavioral model of the antenna. The antenna project automatically includes a sufficiently dimensioned portion of the platform geometry near the antenna. The hybrid solver procedure couples these two projects to provide a consistent evaluation of the installed antenna performance. | |||||||||||||||||||||