Adaptive Liners for Broadband Noise Reduction

Period of Performance: 07/31/2015 - 07/30/2017


Phase 2 SBIR

Recipient Firm

Cornerstone Research Group, Inc.
2750 Indian Ripple Road Array
Dayton, OH 45440
Firm POC
Principal Investigator


This project will combine the advantages of adaptive materials with the simplistic passive design of state-of-the-art acoustic liners to provide the ability to tune them for specific operational frequencies (ex. take-off/cutback, cruise, and approach). Many proposed solutions are not practical from a manufacturing/cost perspective: too complex or add weight to the aircraft that is not justifiable. The requirements for aircraft noise are becoming more stringent with greater emphasis on improvements in performance efficiency and lower fuel consumption. CRG has demonstrated feasibility in implementing adaptive technologies into acoustic liners. The next step is to develop increased understanding at more relevant size scales to demonstrate repeatable liner control performance supported by more extensive acoustic testing runs to understand the initial shifting and increased suppression behaviors that have been observed. Automated cyclic testing of a given adaptive liner parameter will be executed on the order of hundreds of thousands of times to demonstrate the durability of the adaptive material for this application. CRG has focused adaptive liner design on demonstration of tuning reactance to TRL 3-4 in Phase I. CRG will develop multiple integrated prototype demonstrators with flow duct testing to achieve a TRL 5-6 at the end of Phase II.