Definition of a benchmark for low Reynolds number propeller aeroacoustics
نویسندگان
چکیده
Abstract Experimental and numerical results of a propeller 0.3 m diameter operated at 5000 RPM axial velocity ranging from 0 to 20 m/s advance ratio 0.8 are presented as preliminary step towards the definition benchmark configuration for low Reynolds number aeroacoustics. The corresponding rotational tip Mach is 0.23 based on blade sectional chord flow varies about 46000 106000 in operational domain 30% 100% radial range. Force noise measurements carried out low-speed semi-anechoic wind-tunnel compared scale-resolved CFD low-fidelity predictions. Results identify experimental challenges relevance fundamental research questions related transition other effects.
منابع مشابه
Stochastic low Reynolds number swimmers.
As technological advances allow us to fabricate smaller autonomous self-propelled devices, it is clear that at some point directed propulsion could not come from pre-specified deterministic periodic deformation of the swimmer's body and we need to develop strategies for extracting a net directed motion from a series of random transitions in the conformation space of the swimmer. We present a th...
متن کاملA circle swimmer at low Reynolds number.
Swimming in circles occurs in a variety of situations at low Reynolds number. Here we propose a simple model for a swimmer that undergoes circular motion, generalising the model of a linear swimmer proposed by Najafi and Golestanian (Phys. Rev. E 69, 062901 (2004)). Our model consists of three solid spheres arranged in a triangular configuration, joined by two links of time-dependent length. Fo...
متن کاملAsymptotics beyond All Orders for a Low Reynolds Number Flow
The solution for slow incompressible ow past a circular cylinder involves terms in powers of 1= log , times powers of 1= log , etc., where is the Reynolds number. Previously we showed how to determine the sum of all terms in powers of 1= log. Now we show how to go beyond all those terms to nd the sum of all terms containing times a power of 1= log. The rst sum gives the drag coeecient and repre...
متن کاملLow-Reynolds-number swimming at pycnoclines.
Microorganisms play pivotal functions in the trophic dynamics and biogeochemistry of aquatic ecosystems. Their concentrations and activities often peak at localized hotspots, an important example of which are pycnoclines, where water density increases sharply with depth due to gradients in temperature or salinity. At pycnoclines organisms are exposed to different environmental conditions compar...
متن کاملQuiet swimming at low Reynolds number.
The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturba...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Aerospace Science and Technology
سال: 2021
ISSN: ['1626-3219', '1270-9638']
DOI: https://doi.org/10.1016/j.ast.2021.106707