The water tank for testing models of marine engineering structures
(57) Abstract:The invention relates to Maritime transport and for the design model basins. Essence: the pool, having a refrigerating chamber, the channel with water and ice field, the refrigerating machine, a tow truck, and gauge its speed with installation with adjustable stiffness under water and with a height-adjustable fallstrom, and the unit has a stationary base and a removable metal farm in the form of a rod system, limited by two platforms, one of which is still connected with the stationary base and the other movable and fixed on an elastic rods of rectangular cross-section with alternate accession to the mobile platform, thus the opposite ends of the rods are rigidly connected to the stationary platform with the possibility of reversal on the 90oaround the longitudinal axis of the rods. On the mobile platform is installed with a torque device for installation of the tested models, tow truck has a device for moving ice fields on the test model, and the installation is located symmetrically relative to the longitudinal axis of the channel at least half of the DL is in. 7 Il. The invention relates to experimental hydrodynamics of ship and marine engineering structures, and relates to equipment for carrying out their hydrodynamic and ice studies.Known for the water tank for testing models of marine engineering structures, performed by the author. St. USSR N 1000817, CL G 01 M 10/00 containing a water-filled channel and a tow Dolly with electric drive and running wheels in contact with the rails laid along the channel, the test model, the sensors kinematic parameters of the motion model, torque and recording equipment.A disadvantage of the known devices is the inability to test models of ships and offshore ice-resistant engineering structures in ice conditions.Known for the water tank for testing models of marine engineering structures, mainly in the ice containing ice chamber, a water-filled channel, the surface of which is formed ice chillers with cooling system of the ice chamber and a tow Dolly with electric drive and running wheels in contact with the rails laid along the canal, asterousia equipment (for example, Y. N. Alekseev, O. N. Bezzubik, C. A. Belyashov, C. S. Shpakov. The experimental capabilities of the new ice model basin CRI them. Acad. A. N. Krylov. - Shipbuilding industry. Series: ship Design, vol. 13, 1989) is adopted for the prototype. Ice the water tank is widely used for studying the processes of interaction with ice icebreakers and vessels active ice navigation, and predict the resulting loads in different ice conditions typical of those areas where they operated. It also tests the drilling platforms in the reversed motion, when the model of the drilling platform is towed towing carriage in a stationary ice field. These tests have several limitations.A disadvantage of the known devices is the inability to test models of the offshore ice-resistant engineering structures, for example, drilling platforms, in direct motion, i.e. when nadhani them ice fields, and the inability to study the influence of pack formations on the value perceived resistant ground forces and influence them give ground.The claimed invention solves the problem of increasing the efficiency of ispolzovanie towing tank using a tow truck, and models of offshore ice-resistant engineering structures fixedly mounted on an elastic base of the channel of the water tank, which is coming ice formation towing carriage.To do this, the water tank is further provided with an installation submerged in water, with the possibility to adjust the stiffness in the direction of the force on the model of the longitudinal and transverse forces, bending and twisting moments, fallstrom attached to the installation with the possibility of height adjustment, and the unit has a stationary base, such as concrete, rigidly United with the concrete base of the channel, and a removable metal farm made in the form of a rod system, limited by two platforms, one of which is still connected with the stationary base and the other movable, mounted on the rods of rectangular cross-section with alternate accession to the mobile platform, while the opposite ends of the rods are rigidly connected to the stationary platform with the possibility of reversal on the 90oaround the longitudinal axis of the rods, and tested the model through a torque device installed on a movable platform farm and h the I on the test model, and the installation is located symmetrically relative to the longitudinal axis of the channel at a distance of not less than half its length from the beginning of the channel.In Fig. 1 shows a cross-section of the water tank; Fig. 2 is a fragment of a longitudinal section of the water tank; Fig. 3 is a photograph removable metal truss of Fig. 4 is a photograph of part of the farm with the elastic element of Fig. 5 is a photograph of the rods; Fig. 6 is a photograph of the ice model basin; Fig. 7 - ways to connect rods.The device (Fig. 1 and 2) contains concrete channel 1, filled with water 2, on the surface of which is formed ice field 3, is laid along the channel rails 4, which moves through the electric towing truck 5 with the traction wheels 6 mounted on the towing carriage dynamometer 7, located in the cab 8 tow truck registration apparatus, the sensor speeds of 9, the device for moving ice fields - the bulldozer 10, the refrigerating machine 11, prohibitative installation 12, false 13, dynamometer 14 mounted on provopoulos installation, model drilling platform 15.Installation 12 has a stationary base 16, izgotovlenie welded rod system of stainless steel pipes (Fig. 3, 4), limited two platforms 17 and 18 interconnected by a set of elastic elements - rods 19. Elastic elements 19 in the form of rods of rectangular cross section (Fig. 5).Both platforms 17 and 18 is designed as an octagonal structure, consisting of a system of intersecting beams and ties, limited reference path.The lower supporting platform 17 is intended for fixation of the metal farm on the stationary base 16 at the bottom of the ice pool. Concrete base 16 is made square in plan (with dimensions 3x3x0,4 m) and located symmetrically relative to the longitudinal axis of the channel at the optimal distance along the length of the ice basin, 21 - 24 m from the beginning of the channel (0,5 - 0,6 Lk, where Lk is the length of the channel). The optimal distance along the length of the channel selected from the conditions ensure numerazione pack formations of a given size model before drilling platform.For fixing the supporting platform 17 on the stationary base 16 is provided with four ballast box 20, is welded on all four sides of the platform in the plane of the base.Upper carrier platform 18 is intended for fastening on her model of the drilling platform neposredstvanenno located the pipe segment 21 with uniformly diverging from it in the horizontal plane in the radial directions of the steel pipe 22 (8 PCs). This system is connected by welding of pipes 21 and 22 advanced "tied up" in the Central part 8-mew pieces of steel pipes 23. In the joints of steel pipes 22 and 23 are welded to the ends 24 of the sheet of stainless steel with holes for fasteners steel plate (pictured in Fig. 3 not shown) on which is fixed false 13 and the dynamometer 14.Design metal frame that is made in the form of an octagonal rod system, has considerable rigidity with low weight and wide range of capabilities in terms of mounting a variety of models-resistant engineering structures.The installation includes eight elastic elements 19, which are located on the perimeter of the octagonal corners of the farm (Fig. 3, 4, 5). They are all made from the same sheet of stainless steel (sizes of rods 30x10x660 mm). Lower, fixed end of the rod is rigidly fixed in the flange 25 (Fig. 4, 5), which made two pairs of mounting holes located on mutually perpendicular axes. The rods 19 through the flanges 25 are rigidly fixed on the end 26 of the lower platform 17 with the possibility of permutation and spread the symmetry axis of the rods 90oand change the elastic compliance of ustanovki in the corners farm welded knize 27. In knizak 27 holes, through which gap are the upper ends of the rods 19.On the upper movable end of the rods (Fig. 3, 4, 5) is fixed to the cylindrical cups 28, on the outer surface of the thread. If necessary, certain rods may be rigidly connected with the upper platform 18 with nuts 29 on the outer surface of which is cylindrical flange included in the spin nuts into the holes of knits 27 and clamping the upper ends of the rods 19 in the platform 18. When connecting additional terminals 19 to the platform 18 changes the rigidity of the setup. Connection of additional rods may be made in the course of the experiment with a tow truck and does not require dismantling of the installation.The direction of the elastic flexibility of the rods 19 and the corresponding attaching them to the bottom of the bases of the flanges 25 is performed before mounting the farm to the stationary base 16 (in the raised position, air).The design of the elastic suspension of the upper platform, which is set to test the model, gives ample opportunity for selection and adjustment of the elastic flexibility of installation in different directions.Some of the connecting rods implement a certain range of change of compliance for the water tank. When the action on the installation (model PBU) longitudinal force of 2 kN and twisting torque of 400 Nm these four options allow you to specify the longitudinal yielding of the bottom of the water tank (installation) in the range 1 - 10 mm (stages: 1; 1,65; 5; 10 mm) and angle of 0.03' - 0,086' with approximately double adjustable pliability in one experiment by connecting additional terminals. When the mass of the model 1000 kg installation allows you to simulate vibrations with frequency in the range of 2 to 7 Hz.Setting part of the cores with the lowest transverse rigidity in the direction of the longitudinal axis of the basin, and another portion of the rods in the transverse direction, you can set different pliability installation in the longitudinal and transverse directions, as well as against the action of overturning and torsional moments.If necessary, the rods 19 may be excluded from the operation of the plant, in this case, the upper supporting platform 18 "sits" on the lower platform 17 and rigidly fixed therein by a set of stoppers.The device operates as follows. Gather on the shores of the metal farm with two platforms 17 and 18. Establish and fix the rods 19, the dynamometer 14, model 15, false 13. Victore is lowered into the channel of the water tank on a concrete base 16 and is fixed on it with metal chains, which is placed in the ballast boxes 20. Using the refrigerating machine 11 must be ice field 3 or prepare hummocky the formation of fragments of ice. Lower the bulldozer 10. Apply power to the drive electric propulsion system of a towing truck 5. The device is ready for testing.Set the speed of movement of the tow truck 5 in the range 0.001 - 0,030 m/s While the bulldozer 10 is approaching the ice on the test model. The dynamometer 14 measures arising on the model of power. Steps measure the speed of movement of the tow truck in the above range, registering at the same time operating on the model of power. On this first cycle test model with known parameters give the bottom of the pool and frequencies of the device ends. For the second cycle of tests with tow truck 5 plug in the extra cores. For this special key in the form of a pipe with an internal hexagon (under water) wrapped nut 29 to the stop, thereby bonding the upper free ends of the rods 19 with the platform 18. Thereafter, a second cycle of testing the model in other settings pliability of the bottom and the oscillation frequency of the installation. Model BA chamber with a water-lled channel, on the surface of which is formed ice chillers with cooling system of the ice chamber and a tow Dolly with electric drive and running wheels in contact with the rails laid along the channel, the speed sensor truck, torque and registration apparatus, characterized in that the pool is equipped with submerged installation with adjustable stiffness in the direction acting on the test model the longitudinal and transverse forces, bending and twisting moments, fallstrom attached to the installation with the possibility of height adjustment, and the unit has a stationary base, such as concrete, rigidly United with the concrete base of the channel, and a removable metal farm made in the form of a rod system, limited by two platforms, one of which is still connected with the stationary base and the other movable and fixed on an elastic rods of rectangular cross-section with the possibility of reversal on the 90oaround the longitudinal axis of the rod, and the movable platform, the farm installed a torque device for installation of the tested models, and towing Celestino relative to the longitudinal axis of the channel at least half of the length from its beginning.
FIELD: experimental hydromechanics; designing of equipment for conducting hydrodynamic and ice searches of marine engineering facility models in model testing basins.
SUBSTANCE: proposed device includes towing trolley with frame rigidly secured on it; this frame is provided with bar which is connected with model through dynamometers and bearing plate. Dynamometers form three-support force-measuring system; they are provided in each support in form of two interconnected elastic members; one elastic member is made in form of five-rod member provided with longitudinal and lateral force sensors; it is located between two flanges. Second elastic member of dynamometer is made in form of membrane-type elastic member whose membrane is located between rigid rim and rigid central part of this member provided with threaded rod with elastic hinge mounted over vertical axis perpendicularly relative to membrane. Membrane, rim and rigid central part with threaded rod and elastic hinge are made integral. Rim of membrane elastic members is rigidly connected with one of flanges of five-rod elastic member in such way that threaded rod is located along vertical axis of support and is rigidly connected via elastic hinge with bearing plate secured on model. Membrane is provided with resistance strain gages forming vertical force measuring bridge. Second flange of each five-rod member is connected with additional bearing plate secured on bar.
EFFECT: enhanced accuracy of measuring forces and moments.