SU739175A1 - Device for lining the bottom of water beds - Google Patents

Description

(54) DEVICE FOR STRETCHING THE BOTTOM BOTTOM

one

The invention relates to the field of hydraulic engineering, in particular, devices for securing the bottom of watercourses.

A device for fastening the bottom of a watercourse is known, including slabs with hinged connections 1 stacked in staggered order.

The disadvantage of this device is that when there is a high-speed flow around the plates, frontal and lifting forces occur, leading to the destruction of the attachment.

The closest solution known is a device for fastening the bottom of watercourses, including stacked in a staggered pattern on a multilayer filter plates with drainage holes and bevels against the flow 2.

The disadvantage of this device lies in the fact that the hydrodynamic load on the plates from below can exceed the load from above, which leads to the destruction of the device, the disadvantage is also the low damping efficiency of the kinetic energy of the flow.

The purpose of the present invention is to increase the reliability of fastening and increase the efficiency of the quenching of the kinetic energy of the flow.

This is achieved by the fact that the ver. X verge

each plate is made multi-stage

with the ratio of the length of the step to its height,

5 equals 2-9, with drainage holes

located at the intersection of the steps.

FIG. 1 shows a device for securing the bottom of watercourses in longitudinal section; in fig. 2 - the same in terms of; in fig. 3 is a graph of the hydrodynamic pressure coefficient on the plate above C (from the ratio of the step length to its height - | -; Fig. 4 is the graph of the loss coefficient Hahopaf from the ratio of the step length to its height - |.

Claims (2)

The device for securing the bottom of the watercourses includes plates 1, laid on filter 2. The upper edge of the plate is made in the form of steps 3 and has drainage holes 4 at the intersection of the steps. Bottom jets of high-speed flow are in contact with the plates 1 along the upper slightly inclined faces of the steps 3. At the intersection of the steps, vortex zones with reduced pressure are formed, which is compensated by suction of water or air through the drainage holes 4, while the multilayer filter 2 prevents the substrate from attaching ground through the seams and drainage holes. Due to the absence of fastening plates protruding into the flow of the ends and the free flow of water or air through the drainage holes, the frontal pressure on the plate and the lifting force are reduced. In addition, due to the curvature of the bottom jets, a submersible hydrodynamic pressure is developed, ensuring the stability of the plate and allowing a reduction in the thickness of the mount. The loading hydrodynamic pressure on the plate varies depending on the relative sizes of the steps. The largest loading pressure (the coefficient of hydrodynamic pressure Sc) is observed when the ratio of the length of the steps to the height is equal to 3-4, with values less than 2 and greater than 9, the load tends to bullet. The presence of priming hydrodynamic pressure makes it possible to reduce the thickness of the fastening plates by 30 - 50 ° / o and, consequently, to increase the fastening efficiency. The movement of the flow over the multistage surface of the mount is accompanied by the formation of roller zones, curvature and expansion of the bottom jets, which increases the efficiency of quenching the flow by 30-750% compared with the known device. Head loss coefficient | varies according to a dependence similar to the change in the CK coefficient. The largest energy quenching effect is achieved with relative step sizes - 5-7, gradually decreasing with increasing or decreasing step sizes. Claims An apparatus for securing a bottom of watercourses, including stacked in a staggered pattern on a multilayer filter, plates with drainage holes and bevels against the flow, characterized in that, in order to increase reliability; fastening and increasing the efficiency of quenching the kinetic energy of the flow, the upper edge of each plate is made multi-stage with a ratio of the length of the step to its height equal to 2--9. moreover, the drainage holes are located at the intersection of the steps. Sources of information taken into account in the examination 1. The author's certificate of the USSR No 2581116, cl. E 02 B 3/12, 1968. 2. USSR author's certificate number 21827, cl. E 02 B 8/06, 1928. Q, 05 0, 0 0, 02 O g46 Yu Fig.Z 45 eight YU FIG.