A variety of critical performance metrics can be predicted via simulation, including boresight error, transmission loss, bird-strike damage, and deflection under aerodynamic load.
When it comes to aircraft design, engineers must meet standard requirements and consider every scenario. Would the airplane be safe to fly in extreme weather? What if the plane collides with a bird? From takeoff to landing, every potential threat needs to be tested and resolved before design is approved.”
Thanks to technological advancements and cost reduction efforts, aerospace parts are sometimes designed to perform multiple functions. One of these parts is called the nosecone radome, which is a large, thin walled structure that surrounds a radar antenna. The nosecone radome is designed to protect the aircraft’s weather antenna as well as serve as an integral part of the aircraft’s aerodynamic shape. In addition to that, it must also not affect the underlying radar’s signal.
A radome designer must ensure that key performance criteria are met for each of the device’s designated functions no matter what happens during flight. Through high winds, hail, or a high velocity impact from a bird during flight, the designers must plan and test accordingly. Validation is normally accomplished through physical testing. While physical testing can be useful for final design validation, it has several drawbacks. Physical measurements are expensive and time consuming, all of which are multiplied for multi-functional components like radomes. Another drawback to physical testing is it requires complete fabrication of a component before a design can be evaluated.
To cut back on cost and time, computational simulation is often used to verify performance early in the design cycle. This allows the designer to quickly weigh several “what-if” scenarios before the part is built and tested further. A variety of critical performance metrics can be predicted via simulation including boresight error, transmission loss, bird-strike damage, and deflection under aerodynamic load. While a single model cannot fully predict a radome’s behavior, designers can use a technique known as multiphysics simulation.
Multiphysics simulation is an ensemble of physics-based models that can be combined to fully describe a radome’s structural, electromagnetic, and aerodynamic performance. Starting with AcuSolve, a Computational Fluid Dynamics (CFD) solver, designers can predict the air pressure field that surrounds an aircraft during flight. The resulting pressures can then be mapped onto an OptiStruct model to accurately predict the structural response of the radome under aerodynamic load.
FEKO, a high-frequency electromagnetic solver, can also be used to predict the radiation pattern of the radar antenna. A designer can repeat this analysis with and without the radome present to measure the effect that the radar has on the antenna’s signal. Lastly, RADIOSS can be used to predict the damage from a high-speed bird strike.
Together, these models characterize a radome’s performance and can be used to drive informed design decisions while saving engineering time and costs. A multiphysics simulation approach is an invaluable tool for designers of complex, multi-function components.
To read the technical paper associated with this blog post, check out: http://web2.altairhyperworks.com/aircraft-radome-characterization-via-multiphysics-simulation