Noise reducing of aircraft engines

Nowadays, aircraft transportation influences everyday life in our society, but not only by its advantages of efective traveling, but also by its negative impact on environment, therefore us, people. Due to this reason, I decided to concern myself about noise reducing of aircraft engines in this thesis. Research in this field helps to develop comfort of traveling, but also very important fact is noise impact on people living in surroundings near airports. To understand problem to the roots, first we need to know how is noise actually defined. First part of my bachelor’s thesis contains describtion of sound and noise. I’m also focusing on methods for noise measurement and actions, which are used for noise reduction. Greatest success have been made with Variable Geometry Chevrons, which can adjust to different flying conditions and not just reduce noise, but also can keep thrust of the engine at the same level and is also reducing fuel consumtion during level flight. In fourth chapter, you’ll come to know about regulations, which were made to adopt standards and recommended practices concerning aircraft polution. Also very important factor for setting up new standards is process of aircraft testing, so I summed up principles and procedures, which are usedby aviation organizations