In turboprop aircraft, the low-frequency noise field created by propellers is major contributor to interior vibro-acoustic field, which determines a passenger’s discomfort. This paper deals with experimental assessment of an active control (ANC) system for cabin seat headrests using two loudspeakers placed on both sides head create local zone quiet around ears. To deal time-varying disturbances...

In Drosophila, the Apaf-1-related killer (Dark) forms an apoptosome that activates procaspases. To investigate function, we have determined a near-atomic structure of Dark double rings using cryo-electron microscopy. We then built a nearly complete model of the apoptosome that includes 7- and 8-blade β-propellers. We find that the preference for dATP during Dark assembly may be governed by Ser3...

beta-propeller domains composed of WD repeats are highly ubiquitous and typically used as multi-site docking platforms to coordinate and integrate the activities of groups of proteins. Here, we have used extensive homology modelling of the WD40-repeat family of seven-bladed beta-propellers coupled with subsequent structural classification and clustering of these models to define subfamilies of ...

We study noise generation at the blade tips of propellers designed for future electric aircraft propulsion and, furthermore, analyze interrelationship between mitigation and aerodynamics improvement in terms propeller geometric designs. Classical with three or six blades a conceptual joined dual-blades are compared to understand effects tip vortices on aerodynamics. The dual is constructed by j...

surface-piercing propellers (spps) have been widely used in high speed craft due to some desirable features such as high efficiency, omission of resistance of equipment attached to the propeller and proper functioning of cavitation. unlike the submerged propellers, theoretical methods have no significant application on simulation of sppsbecause of problems related to modeling of these propeller...

The present work reports the static behaviour of functionally graded rotating beam based on Timoshenko theory, which includes effect shear deformation. principle virtual displacement is applied to derive a governing equation for (FG) beam, considering centrifugal stiffening effect. B-spline collocation technique employed solve differential and material properties are function power law distribu...

Proteins of the β-propeller fold are ubiquitous in nature and widely used as structural scaffolds for ligand binding and enzymatic activity. This fold comprises between four and twelve four-stranded β-meanders, the so called blades that are arranged circularly around a central funnel-shaped pore. Despite the large size range of β-propellers, their blades frequently show sequence similarity indi...

Inflow turbulence is relevant for many engineering applications relating to noise generation, including aircraft wings, landing gears, and non-cavitating marine propellers. While modelling of this phenomenon well-established higher Mach number aerospace problems, lower applications, which include propellers, still lack validated numerical tools. For purpose, simplified cases extensive measureme...