Russian scientists found a way to reduce aircraft noise 02:00

Scientists from the Perm National Research Polytechnic University (PNRPU) have developed a method to reduce the noise of aircraft turbines. socialbites.ca was informed about this by the press service of the scientific institution.

The loud noise of airplane engines is caused by the movement of the jet stream, which turbulizes the air. According to available data, approximately 3% of the Russian population is exposed to noise near airports.

In modern aircraft manufacturing, harmful noise is limited by increasing the diameter of the engine, which reduces the exhaust velocity. Sound-reducing nozzles are also used – cone-shaped or cylindrical channels that direct gas flows.

In a new study, Perm Polytechnic scientists determined the most efficient nozzle design.

“We looked at tapered, striped and corrugated nozzles of the same size with 12 striped leaves. The experiments were carried out in a chamber with a special installation, in which it was possible to study the noise from a single-wire jet with a flow speed of up to Mach 0.65.

The nozzles were made using a 3D printer. “For them, the flow was generated by two series-connected fans with a power of 45 kW, and six microphones measured the outgoing noise,” said Oleg Kustov, a leading researcher in the laboratory of noise production mechanisms and modal analysis of the Acoustics Research Center. In PNIPU.

Experiments showed that a dozen winged slotted mouthpieces reduce noise across the entire frequency range.

Adding a closely spaced plate simulating an airplane wing produced similar results. Compared to a conical nozzle, the chevron nozzle increased low-frequency noise, while the corrugated one, on the contrary, reduced it.

Polytechnicians noted that practical use of such a nozzle for real aircraft engines is possible if jet noise predominates over other sources of aircraft noise at certification points.

Russian scientists before was created New non-toxic polyethylene adhesive for plywood.