We show that under equilibrium conditions, an anisotropic phase-eld model of a diiuse interface leads to the notion of a divergence-free tensor, whose components are negligible away from the interface. Near the interface, it plays the r^ ole of a stress tensor, and involves the phase-eld generalisation of the Cahn-Hooman-vector. We show that this tensor may be used to derive the equilibrium con...

Abstract. Atmospheric turbulence can be characterized by the Reynolds stress tensor, which consists of second-order moments wind field components. Most commercial nacelle lidars cannot estimate all components tensor due to their limited number beams; most along-wind velocity variance relatively well. Other are however also important understand behavior of, e.g., vertical profile and meandering ...

In this paper we report on (two-component) LDV experiments in a fully developed turbulent pipe flow with a drag-reducing polymer (partially hydrolyzed polyacrylamide) dissolved in water. The Reynolds number based on the mean velocity, the pipe diameter and the local viscosity at the wall is approximately 10000. We have used polymer solutions with three different concentrations which have been c...

We argue that gravity theories in AdS4 are holographically dual to either of two threedimensional CFT’s: the usual Dirichlet CFT1 where the fixed graviton acts as a source for the stress-energy tensor, and a dual CFT2 with a fixed dual graviton which acts as a source for a dual stress-energy tensor. The dual stress-energy tensor is shown to be the Cotton tensor of the Dirichlet CFT. The two CFT...

We use the transfer equation in relativistic form to develop an expansion of the onephoton distribution for a medium with constant photon mean free path, ǫ. On carrying out appropriate integrations and manipulations, we convert this expansion into one for the frequency-integrated intensity. We regroup the terms of the intensity expansion according to both the power of ǫ and the angular structur...

Computational fluid dynamics using the Reynolds-averaged Navier–Stokes (RANS) remains most cost-effective approach to study wake flows and power losses in wind farms. The underlying assumptions associated with turbulence closures are biggest sources of errors uncertainties model predictions. This work aims quantify model-form RANS simulations farms at high Reynolds numbers under neutrally strat...

We investigate the growth and structure of magnetic fields amplified by kinematic dynamo action in turbulence with non-zero kinetic helicity. We assume a simple Gaussian velocity correlation tensor, which allows us to consider very large magnetic Reynolds numbers, up to 10. We use the kinematic Kazantsev-Kraichnan model of dynamo and find a complete numerical solution for the correlation functi...