Flow Resistance in Very Rough Channels

Very-large-scale motions in rough-bed open-channel flow

Long-duration particle image velocimetry measurements in rough-bed open-channel flows (OCFs) reveal that the pre-multiplied spectra of the streamwise velocity have a bimodal distribution due to the presence of largeand very-large-scale motions (LSMs and VLSMs, respectively). The existence of VLSMs in boundary layers, pipes and closed channels has been acknowledged for some time, but strong supp...

Frequency-dependent viscous flow in channels with fractal rough surfaces

Flow Resistance in Sinuous or Irregular Channels

Part 1. The problem and the experiments. General statement-_________________________________ Flow in irregular open channels__________________. Design of experiment_____________._...______ Experimental conditions. ______________________ Experimental results._________________________ Character of the flow; deformation of the free surface. _ _ Conditions below threshold____________________ Condit...

Modelling of Transonic Flow in Very Narrow Channels

The study is focused on the mathematical modelling of leakage flow in very narrow channels. The problem is solved as a two-dimensional non-stationary turbulent compressible Newtonian fluid flow with ideal gas properties. The turbulent flow is assumed to be statistically steady and the mathematical model is described by the non-linear conservative system of the compressible Favre-averaged Navier...

Very Rough Notes : Uncertainty

Lotteries. A lottery L = (p, x) (or gamble) is a vector of payoffs (x1, x2, . . . , xn) with probabilities (p1, p2, . . . , pn). The payoffs might be consumption bundles or monetary payoffs. St Petersburg Paradox. The payoff is 2, where n is the first time the coin comes up heads. The expected value is infinite. If the game lasts just two rounds, it is worth 1 + 1. If it lasts 3 rounds, it is w...