While it only seems like yesterday, it is actually three years ago that I wrote a blog about the important role the Aircraft Environment Control System (ECS) plays in passenger comfort and safety as well as our (ANSYS) participation in Cabin Air Reformative Environment (CARE) consortium.
Those of you who subscribe to the ANSYS Advantage magazine may have read the article on this topic that was published in the most recent edition, but I thought it was about time I provided an update.
I coordinated ANSYS’ participation in the consortium and we were able to learn many important insights into industry requirements for modeling and simulation of the complete environmental control system and feed these into our development cycle to deliver tangible progress and outcomes.
In addition to several high fidelity computational fluid dynamics (CFD) simulations of the inside of the aircraft cabin, the CARE research team performed an extensive simulation study of the whole system — from cabin pressure control software to supply duct work and various components such as pressurization systems. This required a range of simulation approaches from 0D to 3D and control software that were integrated together to form a simulation of the whole system. They were able to perform these coupled multidisciplinary, multifidelity simulations using ANSYS Simplorer, ANSYS Fluent and ANSYS SCADE.
But the CARE team did more than develop a comprehensive simulation of the system. The simulation results were validated with experimental data from the experiments done in a full scale replica of a section of an MD82 aircraft at Tianjin. This work is the subject of the ANSYS Advantage article.
Some of the insights we learned through this research were that coupling simulations of 3D physics in the cabin with the components and control software so that the behavior of the whole system is captured gives tremendous insight about the behavior of the system in real world – more than can be obtained just by looking at aspects of the ECS in isolation or through physical tests and on aircraft experiments alone.
We also identified a number of areas for improvement in simulation capabilities. Two of these were speed — how to improve the speed of the 3D part of the cabin simulation to enable a full flight profile to be simulated in a practical time frame — and how to better make available libraries of system level components that can be coupled to the 3D high fidelity models. In both of these areas our colleagues in product development have made substantive progress.
In terms of reduced order models, there are a number of approaches that are being developed and some of these were applied to the ECS system. You can learn more about two different approaches to reduced order modeling, SVD and LTI by following the links.
For system level simulation, ANSYS 17.0 introduced native support for Modelica that makes available an additional 1500 components from the Standard and Hydraulics and Pneumatics libraries.
As you can see from these developments we highly value the role of key industry consortia like CARE, not only to help current research into key business initiatives such as passenger comfort and safety, but also to make sure that we continue to develop our technology so we can meet the future needs of the industry.
Hopefully it won’t be three years before my next blog on ECS!