Safe landing

Aeronautics research institute simulates aircraft brake system with Simcenter

Sao José dos Campos, Brazil. The Brazilian Aeronautics Institute of Technology (ITA) is involved in training, research and technological development in the field of aeronautics. ITA attaches particular importance to fostering links between research and industry and works in close cooperation with the Brazilian Government to ensure that research aligns as closely as possible to the needs of industry. Issues currently in the spotlight are brake system performance and anti-skid technology in normal and failure modes. To play through possible scenarios, the ITA relies on the use of simulation software from the Siemens PLM Software Simcenter portfolio.

This allows students at the ITA to gather experience with the latest features ofthe advanced simulation setup during their course training. Quite apart from this benefit, ITA has also been able to speed up the evaluation of brake system performance under failure conditions, helping to strengthen Brazil’s position in the highly competitive aeronautical industry.Aircraft brake systems are not only highly complex but also crucial to aircraft safety. The blocking of brakes during braking maneuvers, for instance, must be avoided at all costs.

Traditionally, brake system performance has always been tested by executing multiple load rig tests and test flights. This is a time-consuming and also a costly process and explains why the research team at the ITA set about looking for a new method which would involve simulation of the aircraft’s hydraulic brake system.

A study carried out by the ITA demonstrated the usefulness of system simulation to design and validate the model of a hydraulic brake system in order to assess functionality in both normal operation and in the event of a failure. The experts at the ITA used the LMS Imagine.Lab Amesim from Siemens PLM Software to model the hydraulic system.

Computational parameterized model

The researchers at ITA decided to base their study on a braking system supplied with power by the aircraft’s own hydraulic power generation system. This system is later duplicated to independently provide hydraulic power to each brake. The model generated in LMS Amesim is composed of three elements: the valve assembly, the brake assemblies and the input blocks.

– LMS Amesim is a great tool for quickly creating system models, mainly due to its facility for dealing with the physical blocks found in its software libraries, says Mario Maia Neto, a PhD candidate at ITA. As he explained, this enabled the creation of complex models without the need to write entire mathematical formulas for each subsystem.

– Using LMS Amesim helped us develop a computational, parameterized model for the aircraft hydraulic brake system to assess the behavior of its relevant variables in normal operational conditions and when typical failures are simulated.

Potential far from exhausted

Subsequently the results were compared in order to find a way of compensating for the loss of performance in the “failure mode”. The last step of this computational method was to devise a strategy or actions such as the definition of specific maintenance tasks to maintain the required system level. Neto envisages enormous potential for the new methodology:

– In the current context, modeling and simulation has the potential to improve the execution of several design development activities, such as system architecture study, requirements validation, performance analysis and optimization, safety and assessment, fault detection and diagnosis.

Using LMS Imagine.Lab Amesim from Siemens PLM Software, the experts at the ITA are able to quickly and simply generate a virtual model of a hydraulic aircraft brake system.

The brake system model in LMS Amesim is composed of three elements: the valve assembly, brake assemblies and input blocks.