Macroalgae use flexibility and reconfiguration, i.e. the alteration of shape, size and orientation as water velocity increases, to reduce the hydrodynamic forces imposed in the wave-swept rocky intertidal zone. Quantifying the effects of flexibility on hydrodynamic performance is difficult, however, because the mechanisms of reconfiguration vary with water velocity and the relationship between ...

A numerical procedure to determine the equivalent hydrodynamic dispersion coefficients and Péclet number (Pe) of a fractured rock is presented using random walk particle tracking method. The geometrical effects of fracture system on hydrodynamic dispersion are studied. The results obtained from the proposed method agree well with those of empirical models, which are the scale-dependent hydrodyn...

A hydrodynamic permeability of membranes built up by porous cylindrical or spherical particles with impermeable core is investigated. Different versions of a cell method are used to calculate the hydrodynamic permeability of the membranes. Four known boundary conditions, namely, Happel's, Kuwabara's, Kvashnin's and Cunningham/Mehta-Morse's, are considered on the outer surface of the cell. Compa...

The average scattered intensity is determined by the optical characteristics of particles in dispersion. The normalized time auto-correlation function of the scattered light intensity g (τ ) includes both the optical and hydrodynamic information of particles. From the different characteristics of particles, the particle sizes can be obtained. In this paper, three sizes: the static radius Rs, th...

rayleigh-taylor (rt) instability has a growing importance in many fields including aircraft industry and astrophysics. the development and the growth of rt instability were investigated using sinusoidal disturbances with different wavelength at the interface of two fluids. numerical simulations were performed by solving navier-stokes unsteady equations with the vof formulation. results of the 2...

A hydrodynamic permeability of membranes built up by porous cylindrical or spherical particles with impermeable core is investigated. Different versions of a cell method are used to calculate the hydrodynamic permeability of the membranes. Four known boundary conditions, namely, Happel’s, Kuwabara’s, Kvashnin’s and Cunningham/Mehta-Morse’s, are considered on the outer surface of the cell. Compa...

in this paper, size distribution of nano-bubbles was measured by the reliable and fast method of laserdiffraction technique. nano-bubbles were produced using a nano-bubble generator designed and madebased on hydrodynamic cavitation phenomenon in venturi tubes. a central composite design withresponse surface methodology was used to conduct a five factor, five level factorial experimental designo...

in this research, the total torque input and output shafts were subjected to are used to formulate twodifferential equations using applied dynamics and fluid mechanics. the equations show that the input andoutput torques are a function of the constant geometrical parameters of a torque converter, includinginternal and external diameters of vanes, angle and length of vanes, cross section area be...

Coefficients or hydrodynamic derivatives of autonomous underwater vehicles play a key role in their development. The most popular way for the estimation of coefficient is to implement captive model tests such as straight line tests and planar motion mechanism tests in towing tanks. In this paper, investigation of hydrodynamic derivatives was performed based on the water tunnel maneuvers. Forces...