The CALAS project addressed, by means of computational aero-acoustic (CAA) analysis, low-noise airframe concepts (CfP topic No: JTI-CS-2011-3-GRA-02-018), including a wing-section with and without a side-edge fence (in WP 1) and a landing-gear system with and without low-noise treatments (in WP 2). The main purpose of the project was to evaluate the baseline and other provided low-noise configurations and, additionally, to explore the stochastic method used in modelling noise generation for effective industry use.

The Stochastic Noise Generation and Radiation (SNGR) method and improved variant were used for flow-generated noise source modelling based on RANS solution and, consequently, to provide inputs in CAA analysis using BEM (Boundary Element Method) solver. The analysis further used acoustic analogies in analysis of far-field noise levels. In order to make relevant assessment on the use of the SNGR method for noise-source modelling, not required in the CfP though, additional turbulence-resolving simulation was also planned for a selected configuration in hybridisation with acoustic analogies. This was taken as reference in evaluation of low-noise concepts and of the stochastic method used. In simulations using BEM or turbulence-resolving methods, the effect of liner was incorporated into physically relevant boundary conditions. The project work progress was reflected by a number of step-by-step milestones. The analysis and results were reported in Deliverables and in other GRA-approved reports.

The CALAS project consisted of FOI (SE) and Chalmers (SE) in the consortium and was coordinated by FOI.