|
|
|
|
|
Stephen Schade, Robert Jaron, Lukas Klähn and Antoine Moreau
The rotor?stator interaction noise is a major source of fan noise. Especially for low-speed fan stages, the tonal component is typically a dominant noise source. A challenge is to reduce this tonal noise, as it is typically perceived as unpleasant. There...
ver más
|
|
|
|
|
|
|
|
|
|
|
Edward Canepa, Andrea Cattanei and Fabio Mazzocut Zecchin
The effect of rotational speed and pressure rise on the leakage flow noise radiated by a low-speed axial fan, provided with rotating shroud, has been systematically investigated. The flow in the gap region has been studied by means of particle image velo...
ver más
|
|
|
|
|
|
|
|
|
|
|
Alessandro Zarri, Julien Christophe, Stéphane Moreau and Christophe Schram
The low-speed fans used for automotive engine cooling contribute to a significant part of the global noise emitted by the vehicle. A low-order sound-prediction methodology is developed considering the blade sweep-angle effect on the acoustic predictions ...
ver más
|
|
|
|
|
|
|
|
|
|
|
Gábor Daku and János Vad
This paper presents a critical overview on worst-case design scenarios for which low-speed axial flow fans may exhibit an increased risk of blade resonance due to profile vortex shedding. To set up a design example, a circular-arc-cambered plate of 8% re...
ver más
|
|
|
|
|
|
|
|
|
|
|
Dipali Ghodake, Marlène Sanjosé, Stéphane Moreau and Manuel Henner
The effect of blade sweep has been studied numerically with the Lattice Boltzmann Method on a family of low-speed free-vortex axial fans with sweeps of ±45°. Good overall aerodynamic agreement is first demonstrated on all fans at the design condition, pa...
ver más
|
|
|
|
|
|
|
|
|
|
|
Vincent Domogalla, Lothar Bertsch, Martin Plohr, Eike Stumpf and Zoltán S. Spakovszky
Promising low-noise aircraft architectures have been identified over the last few years at DLR. A set of DLR aircraft concepts was selected for further assessment in the context of sustainable and energy-efficient aviation and was established at the TU B...
ver más
|
|
|
|
|
|
|
|
|
|
|
Esztella Balla, János Vad
Pág. 122 - 129
The paper presents wind tunnel experiments, supplemented with phased array microphone measurements, on 2D basic models of low-speed axial fan blade sections: a flat plate, a cambered plate, and a RAF6-E airfoil. It aims at documenting the establishment o...
ver más
|
|
|
|
|
|
|
|
|
|
|
Stefano Bianchi, Alessandro Corsini, Anthony Geoffrey Sheard
Pág. 45 - 62
This paper describes an experimental investigation of the interaction noise in a jet impacting isolated aerofoils. The authors conducted the study in a low-speed wind tunnel ending in an anechoic chamber, and focussed on the tip region of two types of is...
ver más
|
|
|
|
|
|
|
|
|
|
|
Stan Proskurov, Markus Lummer, Jan Werner Delfs, Roland Ewert, Jochen Kirz, Martin Plohr and Robert Jaron
Overcoming the problem of excessive engine noise at low altitudes is a formidable task on the way to developing a supersonic passenger aircraft. The focus of this paper is on the fan noise shielding during take-off, investigated as part of the DLR projec...
ver más
|
|
|
|
|
|