Motivated by recent experimental and numerical results, a simple unifying picture of intermittency in turbulent shear flows is suggested. Integral structure functions (ISF), taking into account explicitly the shear intensity, are introduced on phenomenological grounds. ISF can exhibit a universal scaling behavior, independent of the shear intensity. This picture is in satisfactory agreement wit...

The simulation of nonlinear ultrasound propagation through tissue realistic media has a wide range of practical applications. However, this is a computationally difficult problem due to the large size of the computational domain compared to the acoustic wavelength. Here, the k-space pseudospectral method is used to reduce the number of grid points required per wavelength for accurate simulation...

Fundamental barriers to advancing weather and climate diagnosis and prediction on time-scales from days to years are partly attributable to gaps in knowledge and the limited capability of contemporary operational and research numerical prediction systems to represent precipitating convection and its multiscale organization, particularly in the tropics. In this regard improvements in convective ...

Convective precipitation-localized, short-lived, intense, and sometimes violent-is at the root of challenges associated with observation, simulation, and prediction of precipitation. The understanding of long-term changes in convective precipitation characteristics and their role in precipitation extremes and intensity over extratropical regions are imperative to future water resource managemen...

[1] A new convective parameterization is introduced that can make use of a large variety of assumptions previously introduced in earlier formulations. The assumptions are chosen so that they will generate a large spread in the solution. We then show two methods in which ensemble and data assimilation techniques may be used to find the best value to feed back to the larger scale model. First, we...

This paper provides a brief summary of some of the recent research completed using radar observations of convective cloud systems associated with the North-Australian monsoon. The key focus is to describe the variability of convective cloud system properties as a function of the large scale regimes characterizing the region. This latter work is linked with the evaluation of the ACCESS model and...

Tropical Storm Edouard (2002) experienced episodic outbreaks of convection downshear within the storm core in the presence of 11–15 m s of ambient vertical wind shear. These outbreaks lasted 2–6 h and were followed by long periods with no deep convection. Flights fromU.S. Air Force reconnaissance aircraft within the boundary layer were used to investigate the cause of one such oscillation. Low ...

Direct and large eddy simulations are performed to study the internal waves generated by the oscillation of a barotropic tide over a model ridge of triangular shape. The objective is to go beyond linear theory and assess the role of nonlinear interactions including turbulence in situations with low tidal excursion number. The criticality parameter, defined as the ratio of the topographic slope ...

In this paper, Turbulent mixed convective heat transfer of water and Al2O3 nanofluid has been numerically studied in a horizontal tube under non-uniform heat flux on the upper wall and insulation in the lower wall using mixture model. For the discretization of governing equations, the second-order upstream difference scheme and finite volume method were used. The coupling of pressure and veloci...

Temporal and spatial variations of convection in South Asia are analyzed using eight years of Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) data and NCEP reanalysis fields. To identify the most extreme convective features, three types of radar echo structures are defined: deep convective cores (contiguous 3D convective echo $40 dBZ extending $10 km in height) represent the...