[1] Gravity waves forced by circular bell-shaped mountains are simulated using the Advanced Regional Prediction System model for four directionally sheared wind profiles W1, W2, W2a, and W2b. W1 is eastward at the surface, while the latter three are southeastward. With the vertical shear directed northward, W1 shows an increasing speed with height, whereas W2, W2a, and W2b are first decelerated...

Abstract The drag coefficient under tropical cyclones and its dependence on sea states are investigated by combining upper-ocean current observations [using electromagnetic autonomous profiling explorer (EM-APEX) floats deployed five cyclones] a coupled ocean–wave (Modular Ocean Model 6–WAVEWATCH III) model. estimated averaged over all storms is around 2–3 × 10 −3 for wind speeds of 25–55 m s −...

Computing the forces acting from a surrounding air phase onto an SPH free-surface fluid is challenging. For full multiphase simulations the computational overhead is significant and stability issues due to the high density ratio may arise. In contrast, the air-fluid interactions can be approximated efficiently by employing a drag equation. Here, for plausible effects, the parameterization is im...

This paper describes the various frequency domain methods which may be used to analyze experiments data on the force experienced by a circular cylinder in wave and current to estimate drag and inertia coefficients for use in Morison’s equation. An additional approach, system identification techniques (SIT) is also introduced. A set of data obtained from experiments on heavily roughened circular...

A new nonlinear analytical model for canopy flow over gentle hills is presented. This model is established based on the assumption that three major forces (pressure gradient, Reynolds stress gradient, and nonlinear canopy drag) within canopy are in balance for gentle hills under neutral conditions. The momentum governing equation is closed by the velocity-squared law. This new model has many ad...

in this study, changes in speed and turbulence intensity in the wake of a peugeot model and the drag coefficient changes with increases vehicle speed in unsteady flow measured and evaluated. the blow open circuit wind tunnel to simulate fluid flow is used. disturbances and nominal maximum speed of the device, respectively is, 30 m / s and 0.01%. has been continuously increasing speed by an inve...

Because of limited wind fetch and shallow water depth, air-sea interaction in coastal oceans is very different from that in the open ocean. Surface waves in coastal oceans often have a sea state far from the fully-developed sea. As shown in recent observations (Donelan et al., 1993; Garrett, 1997), drag coefficient is a strong function of wave age. At the same wind speed, the air-sea momentum f...

Aiming at the undulating member bar, three kinds of wavelength models are established. The flow characteristics bar with space angle attack analyzed by large eddy simulation method under high Reynolds number, its velocity and pressure distribution different wavelengths studied, time frequency domain circumferential coefficient, resistance lift discussed. results suggest that greater fluctuation...

Numerical investigation of flow around a square cylinder are presented using the multi-relaxation-time lattice Boltzmann methods at different Reynolds numbers. A detail analysis are given in terms of time-trace analysis of drag and lift coefficients, power spectra analysis of lift coefficient, vorticity contours visualizations, streamlines and phase diagrams. A number of physical quantities mea...