We have performed a fully three-dimensional general relativistic magnetohydrodynamic (GRMHD) simulation of jet formation from a thin accretion disk around a Schwarzschild black hole with a free-falling corona. The initial simulation results show that a bipolar jet (velocity ≈ 0.3c) is created as shown by previous two-dimensional axisymmetric simulations with mirror symmetry at the equator. The ...

Local scouring in the downstream of hydraulic structures is one of the important issues in river and hydraulic engineering, which involves a lot of costs every year, so the prediction of the rate of scour is important in hydraulic design. Side weirs are the most important of hydraulic structures that are used in passing flow. This study investigate the scouring due to falling jet from side weir...

P. Novak, Consultant In his paper the author has made a very useful contribution to the subject of prediction of oxygen content downstream of spillways, particularly in the case of surface aeration. However, some of the analysis referring to previously published results of oxygen uptake at hydraulic structures is not always rigorous enough. 40. The equations quoted for Avery and Novak apply to ...

A steel ball impacting on a bed of very loose, fine sand results in a surprisingly vigorous jet which shoots up from the surface of the sand [D. Lohse, Phys. Rev. Lett. 93, 198003 (2004)10.1103/PhysRevLett.93.198003]. When the ambient pressure p is reduced, the jet is found to be less vigorous [R. Royer, Nature Phys. 1, 164 (2005)10.1038/nphys175]. In this Letter we show that p also affects the...

Goldman, Joichi, and White proved a beautiful theorem showing that the falling factorial generating function for the rook numbers of a Ferrers board factors over the integers. Briggs and Remmel studied an analogue of rook placements where rows are replaced by sets of m rows called levels. They proved a version of the factorization theorem in that setting, but only for certain Ferrers boards. We...

The device for applying meliorants is designed the distribution of nutrients, presented in liquid form, sublap space a plane-cutting tillage tool. Distribution carried out by spraying meliorants, which allows you to saturate fertile soil layer with nutrients and substances obtain high yield. Spraying occurs due directional effect compressed air on jet, as result jet breaks up into finely disper...