in dynamic analysis of floating structures, the designer needs to know the wave forces due to incident and scattered waves on the structure. in this work, the flow field around the body is solved based on the potential theory with considering the free surface and sea bed effects. using this theory, the wave forces exerted on two typical sea buoys with spherical and disc-type bodies are determin...

The present paper contains the test results of a planing catamaran model. The aim of the tests was to study the effect of hydrofoil in these types of crafts. First, experiments were carried out on the bare body (i.e. without hydrofoils) to obtain non-dimensional hydrodynamic resistance coefficient versus speed. Then, the model with hydrofoils, by various locations and attack angles were subject...

The hydrodynamic studies of fluidized bed reactor has been reported in terms of pressure drop, minimum fluidization velocity and bed volume expansion to contribute to the optimization of the CNTs production parameters in fluidized bed reactors. Minimum fluidization velocity and pressure drop, as the most important parameters, were taken into account for the investigation of the hydrodynamic beh...

The problem of expansion of a dilute granular gas consisting of smooth, inelastic hard spheres into vacuum was investigated by three different methods: both (1) analytical and (2) computational (CFD) treatments of a hydrodynamic model, and (3) by Discrete Element Method (DEM) simulation. Furthermore, the systems were followed for long times, over which the granular kinetic energy decreases by s...

Self-propelled colloids (swimmers) in confining geometries follow trajectories determined by hydrodynamic interactions with the bounding surfaces. However, typically these interactions are ignored or truncated to the lowest order. We demonstrate that higher-order hydrodynamic moments cause rod-like swimmers to follow oscillatory trajectories in quiescent fluid between two parallel plates, using...

Most Codes such as API and BSI recommend Morison’s equation to estimate hydrodynamic forces on offshore structures. Significant differences exist among these Codes due to using different methods of analysis and estimation of force coefficients. In this paper, data from full scale tests have been used to evaluate random waves and uniform current actions on the smooth piles.&#10 Four time an...

In this paper a computational method is presented for predicting the unsteady hydrodynamic forces acting on partial immersed propeller (SPP). In order to simulate the unsteady viscous flow around a SPP, a Reynolds-Averaged Navier–Stokes (RANS) solver is used. The time-accurate calculations are made by applying the sliding mesh method. Structured and unstructured mesh techniques are used. ...

The evolution to the steady state of a granular gas subject to simple shear flow is analyzed by means of computer simulations. It is found that, regardless of its initial preparation, the system reaches (after a transient period lasting a few collisions per particle) a non-Newtonian (unsteady) hydrodynamic regime, even at strong dissipation and for states where the time scale associated with in...

In this paper, by using a quantum hydrodynamic plasma model which incorporates the important quantum statistical pressure and electron diffraction force, we present the corrected plasmon dispersion relation for graphene which includes a k quantum term arising from the collective electron density wave interference effects (which  is integer and constant and k is wave vector). The longitudinal ...