surface roughness is a significant parameter which determines the efficiency of optical components. surface damages induced by grinding strongly influence the mechanical strength and optical quality of optical glasses. it is meaningful to rapid evaluate the surface roughness through the measurement of different grinding parameters. in this study, a cup diamond wheel (d64) is used in grinding pr...

AR = cavity aspect ratio a = speed of sound b = cavity half-width ~ C = dynamic compressibility c = phase speed cp = specific heat at constant pressure f = frequency H = cavity depth k = wave number m = propagation constant P = pressure Pr = Prandtl number R = reflection coefficient p = acoustic pressure pi = initial pulse amplitude Re = acoustic Reynolds number s = cavity spacing T = temperatu...

In this study, an unsteady aerodynamic simulation is performed to realize the influences of platform surge motion on the aerodynamic performance of a high capacity offshore floating wind turbine. A dynamic model with pitch angle control system is utilized to propose a more realistic model of wind turbine and also achieve the rated condition of the rotor. The transient effect of platform surge m...

In this work we solve the set of hydrodynamical equations for accretion disks in the spherical coordinates (r,θ,ϕ) to obtain the explicit structure along θ direction. We study a two-dimensional advective accretion disc in the presence of thermal conduction. We find self-similar solutions for an axisymmetric, rotating, steady, viscous-resistive disk. We show that the global structure of an advec...

Acoustics is new on Mars: it allows the characterization of turbulence at smaller scales than previously possible within lowest part Planetary Boundary Layer. Sound speed measurements, by SuperCam instrument and its microphone onboard NASA Perseverance rover, allow retrieval atmospheric temperatures 0.77 m above ground, 3 Hz, with a ?10 ms response time that 20 to 100 times shorter for typical ...