by National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Division, For sale by the National Technical Information Service] in [Washington, D.C.], [Springfield, Va .
Written in English
|Other titles||Airfoil self noise and prediction.|
|Statement||Thomas F. Brooks, D. Stuart Pope, Michael A. Marcolini.|
|Series||NASA reference publication -- 1218.|
|Contributions||Pope, D. Stuart., Marcolini, Michael A., United States. National Aeronautics and Space Administration. Scientific and Technical Information Division.|
|The Physical Object|
A prediction method is developed for the self-generated noise of an airfoil blade encountering smooth flow. The prediction methods for the individual self-noise mechanisms are semiempirical and are based on previous theoretical studies and data obtained from tests of two- and three-dimensional airfoil blade sections. The self-noise mechanisms are due to specific boundary Cited by: Get this from a library! Airfoil self-noise and prediction. [Thomas F Brooks; D Stuart Pope; Michael A Marcolini; United States. National Aeronautics and Space Administration. Scientific and Technical Information Division.]. The difference in the self-noise prediction between the frozen and non-frozen gust assumptions is about 2 dB at high frequencies. Thus, the frozen-turbulence assumption appears to be reasonably valid for making airfoil self-noise predictions. Broadband self-noise directivity and the effect of Cited by: The former is a result of the interaction of the boundary layer of the airfoil with the trailing edge and the latter results from the interaction of the existing turbulence in the wind with the airfoil. In the model, the airfoil self-noise prediction is based on the functions given by .
The prediction methods for the individual self-noise mechanisms are semiempirical and are based on previous theoretical studies and data obtained from tests of two- and three-dimensional airfoil. Request PDF | A Pareto Front Based Evolutionary Model for Airfoil Self-Noise Prediction | According to NASA's report on the technologies that could reduce external aircraft noise by 10 dB, a. The application of open-porous materials is a possible method to effectively reduce the aerodynamic noise of an airfoil. However, the porous consistency may have a negative effect on the aerodynamic performance of the airfoil, since very often the lift is decreased while the drag increases. In a recent investigation, the generation of trailing edge noise of a set of airfoil models made from Cited by: 1. The development of physics-based noise prediction tools for analysis of aerodynamic noise sources is of paramount importance since noise regulations have become more stringent. Direct simulation of aerodynamic noise remains prohibitively expensive for engineering problems because of the resolution requirements. Therefore, hybrid approaches that consist of predicting nearfield flow quantities.
The full text of this article hosted at is unavailable due to technical difficulties. Arcondoulis E, Doolan C, Zander A () Airfoil noise measurements at various angles of attack and low Reynolds number. In: Proceedings on Acoustics Google Scholar Brooks T, Pope D, Marcolini M () Airfoil self-noise and by: 1. The blades of the wind turbine are divided into a number of airfoil sections or blade elements. The two-dimensional airfoil self-noise prediction theory is applied for each blade section and the total noise level is determined by summing up all the noise sources. For the i th Cited by: 1. RANS Based Prediction of Airfoil Trailing Edge Far-Field Noise: Impact of Isotropic and Anisotropic Turbulence Proceedings of the 14th AIAA/CEAS Aeroacoustics Conference, Vancouver, Canada, AIAA Paper No. Cited by: