We use cookies to make sure our website better meets your expectations.
You can adjust your web browser's settings to stop accepting cookies. For further information, read our cookie policy.
IN Warsaw
Exchange Rates
Warsaw Stock Exchange - Indices
You have to be logged in to use the ReadSpeaker utility and listen to a text. It's free-of-charge. Just log in to the site or register if you are not registered user yet.
Perforation Helps Aviation
August 29, 2012   
Article's tools:

A Polish doctoral student is conducting research that may help the aerospace industry deal with problems such as noise, turbulence and breakdowns.

The researcher, Jan Artur Szumski, is the winner of the Innodoktorant scholarship program for innovative doctoral students.

Engineers who design and build aircraft are on a never-ending quest to improve aircraft performance, prevent failures, save fuel and eliminate vibrations that make air travel uncomfortable. Szumski is conducting research that aims to address these and other challenges. His research concerns laws that govern the flow of air through aircraft components.

Szumski is searching for a rule to describe how the air flows through airplane wings and turbine blades. The young scientist is conducting his experimental research under the guidance of Prof. Piotr Doerffer at the Polish Academy Sciences’ Szewalski Institute of Fluid-Flow Machinery in Gdańsk.

The air penetrates Szumski’s models through holes drilled in the models’ walls. The diameter of these holes, their distribution and the angle at which they drilled are all crucial factors because they determine how the air which penetrates a model’s wall interacts with the airflow around the model.

Laws so far derived by researchers studying this field are based on geometrical factors such as the holes’ diameter and the diameter-to-depth ratio. However, the actual geometrical parameters of the holes are difficult to determine. In his approach to the problem, Szumski minimizes the importance of geometrical parameters and instead he made his method rely on differences in the air pressure on either side of the perforated plates he examines. He is also studying the force of the air which penetrates through the plate. In other words, his take on the problem focuses on the airflow rather than the mechanics. Szumski is particularly interested in models involving supersonic airflow speeds.

Szumski cites electricity-generating turbines as an illustration of the practical aspect of his research. “When they produce electricity, the turbines work in increasingly disadvantageous conditions when it comes to the materials they are made of,” Szumski says. “Temperature is the main problem. A perforated surface can significantly reduce the temperature of rotating turbine blades, as a result of which the entire machinery can work failure-free for a longer period of time.”

One of the biggest problems faced by the aviation industry is noise. Perforation helps break a strong perpendicular shock wave into a succession of smaller, diagonal waves. As a result, air pressure peaks are split in time and space so that, for example, helicopter rotors produce less noise.

Major aviation problems also include flow separation, that is situations where, in certain conditions, the flow of the air breaks away from the surface of a wing. The spots where flow separation occurs tend to vibrate and flutter, which can put an extreme strain on the aircraft structure. “Flying in a plane that behaves like a car on a bumpy road is hardly enjoyable,” says Szumski. “A perforated surface placed in front of a flow separation area stabilizes such spots and reduces their size.”

According to Szumski, the commercial application of the results of his research should be of interest to the energy sector and the aerospace industry, including aircraft design companies, aviation consortiums, design studios and producers of computational codes employing Computational Fluid Dynamics methods.

The InnoDoktorant program of scholarships for doctoral students is supported by the European Union as part of its Human Capital Operational Program for the 2007-2013 period.

Karolina Olszewska
Latest articles in The Polish Science Voice
Latest news in The Polish Science Voice
Mercure - The 6 Friends Theory - Casting call
© The Warsaw Voice 2010-2018
E-mail Marketing Powered by SARE