We prove the existence of invariant curves for a T – periodic Hamiltonian system which models a fluid stirring in a cylindrical tank, when T is small and the assigned stirring protocol is piecewise constant. Furthermore, using the Numerical Analysis of the Fundamental Frequency of Laskar, we investigate numerically the break down of invariant curves as T increases and we give a quantitative est...

Let S be a set of n points in Rd in general position. A set H of k-flats is called an mk-stabber of S if the relative interior of any m-simplex with vertices in S is intersected by at least one element of H. In this paper we give lower and upper bounds on the size of minimum mk-stabbers of point sets in Rd and in general position. We study mainly mk-stabbers in the plane and in R3.

during recent years oil products has decreased because of growing population and increasing demand to oil products and decreasing of crude oil extraction at compare to export. however, to achieve suitable levels of production, the use of improved technologies should be considered. another way to prevent the evaporation and leakage from oil storage tanks and their products are using of storage t...

Research on increasing the buckling strength of tanks carrying fluid and also cylindrical shells of thin-walled steel in civil engineering and mechanics is important. This is due to the widespread use of these structures in the industry. Due to the low thickness of the body and also due to the pressure forces entering these tanks, these structures are exposed to lateral buckling. In this resear...

The article is devoted to improving the accuracy of system for measuring and controlling level liquid materials in horizontal cylindrical tanks. task ensuring continuous accurate control level, volume mass petroleum products, taking into account shape bottom tank, set. In order improve device, a laser rangefinder installed, which allows you determine distance from tank lid point surface product...

At a brewery, the base plate-to-shell weld seam of a 90-m(3) vertical cylindrical steel tank failed catastrophically. The 4 ton tank "took off" like a rocket leaving its contents behind, and landed on a van, crushing it. The top of the tank reached a height of 30 m. The internal overpressure responsible for the failure was an estimated 60 kPa. A rupture disc rated at < 50 kPa provided overpress...

The general context of this work concerns the latent heat storage (cold storage) by encapsulated spherical nodules of 7.7 cm in diameter containing a Phase Change Material (PCM) and filling a cylindrical tank (about 2500 nodules per m3). During the storage process, a cold heat transfer liquid flows through the tank to crystallize the PCM inside the nodules. The stored energy is released when a ...

In this paper, a numerical study of a chaotic mixing process that involves a highly viscous fluid is presented. The investigated mixer is composed of two circular rods maintained vertically inside a cylindrical tank. The tank and the rods are heated and can rotate around their revolution axis. Chaotic flows are obtained by imposing a temporal modulation of the rotational velocity. Unsteady equa...