Editorial for special issue on acoustic liners

Abstract

I am honored to present to the readers this special issue of the International Journal of Aeroacoustics on Acoustic Liners. Acoustic Liners have been studied since the introduction of turbojet engines and implemented shortly thereafter. Currently, almost all commercial turbofan engines nacelles have acoustic liners installed in somemanner. This Special Issue onAcoustic Liners provides 16 papers across a breadth of material – from analytical and numerical modelling to unique test rigs to evaluation of liner concepts. Contributors from academia, government agencies, and industry throughout the international community provide a range of insight. The focus is on the tried-and-true passive liner paradigmwhich continues to be the principal method of achieving noise reduction. The passive liner concept is straightforward – however, higher bypass ratios and shorter engine nacelles in advanced turbofans, as well as continuing demand for increased noise reduction while mitigating any performance impact, necessitates a continual improvement in liner acoustic performance and installation in novel locations. Therefore, continued study by the aeroacoustics community in this area is necessary to maintain our critical contribution to the improvement of the quality of life in communities near airports. I thank the authors for their contributions whose creativity and expertise are the basis of this issue. I sincerely appreciate the reviewers for their time spent in reviews and providing feedback which greatly improved the quality of the papers. I am grateful to the Editor-in-chief, Dr Ganesh Raman, and the International Journal of Aeroacoustics for providing an opportunity for publishing this special issue. In addition, my thanks are extended to Dr Ed Envia, Assistant Editor, who handled the papers for which I was an author.