LV13977B - The generator of vertical airstream for a free-flying of human - Google Patents

Abstract

Generator of vertical airstream is the main unit of stationary, demountable or mobile installations of open type for creating the conditions of free-flying of human in the vertical airstream. All elements of proposed generator, including aerodynamical screw, are compactly located inside of the one short vertical axisymmetric gas-dynamic channel (height of the channel is approximately equal to radii of the screw), which consists of the curvilinear inlet device and coaxially connected to it rectilinear cylindrical channel. In the initial section of cylindrical channel there is coaxially mounted the aerodynamic screw, which creates the air flow, and behind it at the short distance coaxially located the device made from sheet material, which is simultaneously directing and smoothing flow, and consists from the coaxial rings of equal height, truncated cones and radial curvilinear blades with the constant or variable along radii geometric twist. Blades are mounted between the rings and the cones along radii and are displaced on a certain angle relative to each other in such a way that they would be located inside the directing and smoothing device in checkerboard order and in the central region of the directing and smoothing device number of blades was less than on the periphery. In the center of directing and smoothing device opposite to the propeller hub for eliminating the velocity "drop" zone near the axis of airstream are coaxially mounted two thin-walled cones which are tapered and truncated along stream, between the walls of which are fixed several short flat blades, twisting a stream between cones. The motor of screw or its reducer, are coaxially mounted on the inlet or before the inlet device in a zone of the low velocities of flow.

Description

DESCRIPTION OF THE INVENTION

The invention relates to equipment for the free floating of a human being or the creation of flight conditions in a vertical air stream producing a vertical aerodynamic force equal to or greater than human gravity. Such devices are known and are used as surface trainers for simulating long-range parachute jumping as well as for demonstrating sporting entertainment to the public.

Analysis of prior art

Stationary Vertical Wind Tunnels closed-circuit closed [1] or non-closed [2] aerodynamic tube installations with vertical flow in the working area bounded by the side walls are known. In a closed aerodynamic tube, the flow circulates through a closed loop, which allows for partial use of the mechanical energy already present in the flow. In an open tube, the flow is discharged into the atmosphere and is not reused, so that the mechanical energy inherent in the flow is completely lost. Such equipment has the following disadvantages:

- space restricted for flights with rigid side walls of the working area of the tube and air-tight lower and upper safety nets;

- it is not possible to perform sporting performances with group flights for a large number of spectators, such as stadiums, fairs, etc .;

- the high cost of creating such equipment and the lack of facilities for its rapid assembly and dismantling in the event of relocation.

Stationary [3] and mobile [4, 5] open-air units with free vertical air jet ("Aerodium" units) are known, in which the jet working area is not restricted to the side walls and the upper air-permeable screen. Such equipment shall have an open circuit aerodynamic circuit. Aerodium type equipment is mainly intended for amateur flights and sports performances, as it allows to fly in the free vertical jet working area about 1 to 20 meters above the lower air-permeable safety net. They can be quickly dismantled, transported and assembled at the new location. The main structural elements of vertical air jet generation systems in open-type Aerodium equipment are:

- an aerodynamic screw or fan connected to the engine;

- an inlet duct through which air is supplied to the screw or fan (not provided in some analogs);

- an outlet duct where, in general, guide vanes and a leveling device are fitted inside to prevent the flow from being twisted behind the screw (fan) and to form a smooth flow of air at the outlet of the lower air-permeable network.

The disadvantages of known air jet systems in open Aerodium units are the irrational design of the aforementioned elements and the increased operating costs due to high flow energy losses both in the individual elements and in the system as a whole, combining the elements into one complex without considering their aerodynamic interactions.

The main drawbacks of known analogue [3-5] elements of vertical air jet systems are:

- the absence of a specially profiled inlet section of the inlet duct, which causes the flow to drop off near its inlet edges and significantly increases energy loss in the system;

- the horizontal position of the fan or aerodynamic screw axis requires a rotation of the flow behind the fan by 90 ° in order to obtain a vertical jet, by means of a special guide channel or blades which causes asymmetry of the jet speed profile and additional energy loss;

- in analogue designs, the aerodynamic screw is mounted with an unjustifiably large gap between its blade ends and the inside walls of the coaxial limiting ring or other channel, which significantly increases the energy loss in the machine and reduces the jet velocity behind the screw;

- flat radial blades used in leveling device designs are ineffective, since their entrance edges, which have no corresponding curvature in the initial stages, create tear zones and result in high flow energy losses at the entrance of the leveling device and aerodynamic or blade slit blades. the absence of a geometric rotating blade radius makes it impossible to eliminate the twist of the flow behind the screw and the "drop" in velocity near its axis, which makes it difficult for amateur and professional flights;

- relatively low airflow quality, which makes it virtually impossible to use known closed-loop stationary equipment improvement techniques, by creating screw-profiled nozzles with high flow narrowing to smooth out the hornbomb type ripple and velocity profiles in the jet.

The object of the invention is to simplify the design, to improve the operation and aerodynamic properties of the generated jet, and to reduce the costs of operating open systems designed to create conditions for human flight in vertical airflow.

The stated objective is achieved by using an air-jet generator which, unlike the known design of a vertical air-jet generating system (generally comprising a feed duct, a motorized air screw, a duct and a leveling device), flow is compactly arranged in a single, specially shaped short, symmetrical, gas-dynamic channel with an aerodynamic screw coaxially cylindrical, but a device fixed at a short distance from the screw that simultaneously straightens and smoothes the flow, forming the free jet generated by the generator stage, inside.

List of drawings:

Fig. 1 Diagram of the vertical air jet generator (component view);

Fig. 2 Overview of the vertical air jet generator;

Fig. 3 Variation of layout of cylindrical rings and truncated cones of the leveling apparatus;

Fig. 4 Variation of a single row of blades in a device for straightening and leveling the flow behind the aerodynamic screw;

Fig. 5 'Aerodium' type fixed installation with vertical air jet generator;

Fig. 6 "Aerodium" type mobile unit with vertical air jet generator;

The construction of the gas channel with generator jet forming and forming elements consists of the following elements:

(a) special curvilinear input devices (eg, an axisymmetrical thin-walled channel with a smooth curvilinear shape in the form of a Bemulli lemniscate);

(b) a cylindrical straight channel coaxially connected to the input device, the inlet being coaxially mounted with an aerodynamic screw, the inner diameter of the cylindrical channel being greater than 2 to 2.5% of the screw diameter;

(c) a straightening and leveling apparatus: fixed and coaxially fixed in said cylindrical passage; is placed behind the screw at a short distance from it (approximately 30 to 50 mm from the screw construction); not projecting beyond the outlet of the cylindrical channel; it has a height of 0.1 to 0.4 of the screw diameter; consisting of coaxial rings, truncated cones and radially curved blades (generally, the blades have a variable geometric twist in the radial direction and a curvature of the profile sections that adhere to the front edges of the profiles), with: the blades mounted between the rings and the cones relative to each other at a given angle such that they are generally in a chess pattern; the number of blades installed in the central area of the leveling device is less than in the periphery; in the center of the leveling device, two flow-tapered truncated thin-wall cones are coaxially mounted opposite the screw hub, between which several flat blades with geometric torsion are fixed.

The vertical air jet generator operates as follows. The rotating screw 1 creates a pre-pressure zone and creates an air flow 2 which moves from the bottom upwards in the inlet device 3 of the gas channel 4 and reaches the screw.

Input device 3 with smooth curvilinear shape Bemulli in the form of a lemniscate with respect to axially symmetrical flow without the formation of local flow-off zones and a low energy loss coefficient before the screw. The short special shape gas channel 4 (average channel height approximately half of the screw diameter) is designed to reduce energy loss in the generator and increase its efficiency by forming a non-sharp bend, flow break and stagnant zone with parasitic macro-vortex.

The aerodynamic screw is located in the cylindrical portion 5 of the gas dynamic conduit 4 which adjoins the inlet device 3. Depending on the height restrictions of the gas conduit 4, the aerodynamic screw is mounted just behind the inlet device in the cylindrical channel inlet or at less than half the screw diameter. To increase the flow rate of the screw, the gap between the screw blade ends and the inner surface of the cylindrical part 5 must not exceed 2.0 to 2.5% of the screw diameter.

As a result of the action of the screw, a flow 6 is formed which moves upwardly in the cylindrical channel 5 with a high vertical speed and a known angular velocity 7 (flow twist) with respect to the vertical "y" axis of the gas channel. The vertical velocity profile of the flow 6 in the cross-section is relatively uneven due to the twisting of the flow behind the screw as well as the emergence of the thrust zone behind the screw hub 8 and the velocity "drop" near the channel axis. In order to create a non-twisted air jet 9 at the exit from the gas channel with a sufficiently uniform vertical velocity profile, a device 10 is located coaxially behind the rotating screw (approximately 30 to 50 mm from the screw member) to straighten and smoothen the flow 6.

The device 10 is made of sheet material and as shown in FIG. consists of a plurality of rings 11 of equal height, slotted cones 12, 13 and 14 and radially curved blades 15 having a continuous or radially variable geometric twist. In order to reduce the energy loss caused by the flow of the flow to the blades, the blade profiles in the sections adjacent to their front edges are curved, leaving the other sections of the profiles linear. The blades 15 prevent the twist 7 of the air flow 6 behind the screw 1 and partially equalize the "drop" area of the vertical velocity near the jet axis. They are mounted between the rings 11 and the cones in the direction of the sections 12 and 13, which are offset by a certain angle relative to each other, so that they are generally arranged in a chess arrangement in the leveling device. In the central part of the leveling device, the number of blades is lower than in the periphery, in order to reduce the excessive obstruction of the free space. This arrangement of the blades facilitates the assembly of the leveling device and facilitates the smoothing of the generator's jet 9 velocity profile, which does not enter the screw macro-vortex, as it is divided into smaller vortex channels formed by the blades and rings or cones.

The outer cylindrical ring 11 of the leveling device 10 is rigid and coaxially fixed inside the cylindrical channel 5 so that it does not extend beyond the limits of the gas dynamic channel. The height of the straightening and leveling devices is chosen within the range of 0.1 to 0.4 of the screw diameter depending on the screw hub diameter and the height restrictions of the gas channel 4.

Two coaxially tapered thin-wall tapered cones 13 and 14 are provided coaxially opposite the screw hub 8 to lock the generator-generated flow thrust zones behind the screw hub 8 and to reduce velocity "drop" near the jet axis to the center of the straightening and leveling device 10. 16 with a geometric twist to spin the flow between the cones in the opposite direction of the screw rotation.

The diameters of the base circles of the cones 13 and 14 must be slightly larger than the diameters of the inactive zone of the screw 1 hub 8 and the hub blade. The maximum cone expansion angle of the device 10 is selected from the non-flow failure conditions inside the annular conical channels.

Rotation of the aerodynamic screw of the air jet generator is provided by an electric motor 17 or an internal combustion engine 18 connected to the screw shaft directly or through a gearbox 19. In both cases, the engine or gearbox is coaxially installed before entering the gas channel or its inlet stream.

The proposed air-jet generator is of universal design and is intended to be used as a separate module in stationary (Fig. 5), demountable and mobile (Fig. 6) open Aerodium type devices for human vertical flight.

Sources of information:

1. Patents US 7,156,744 B2; 2/2007;

2. Patents US 6,083,110'4 / 2000;

3. Patents US 5,318,481; 7/1994;

4. United Kingdom Patent Application 2,288,772 A; 11/1995;

5. Patent Application UK 2,290,484 A; 1/1996.

Claims (4)

Claims 1. A vertical air jet generator for human free flight comprising an air inlet, an air-powered propeller, an air inlet, and a leveling device, characterized in that, with a view to simplifying design, improving the aerodynamic performance of the jet and reducing operating costs, all the air-jet generator elements are compactly housed inside a single short vertical vertical axis symmetrical gas channel approximately average screw height and consisting of a curvilinear inlet device (eg thin wall, symmetrical axis with a smooth axis) curvilinear shape (Bernoulli in the form of a lemn plate) and a coaxially connected rectilinear cylindrical channel with an aerodynamic screw (the diameter of the channel being greater than 2.0 l up to z 2.5%), but a short distance (not less than 30 to 50 mm and not more than half of the screw diameter) behind the screw is fixed and coaxially made of a sheet material device (height 0.1 to 0, 4 screws), which at the same time straighten and smoothen the air flow and consist of coaxial rings of equal height, truncated cones and radial curved blades, whereby the blades generally have a radially variable geometric twist and a section of profiles adjacent to the profiles. facets, curvature; said blades being arranged between the rings and the cones at a right angle to each other such that they are generally disposed in a leveling device in a chess-like manner; the number of blades installed in the center area of the equalizer is lower than in the periphery. 2. An air-jet generator according to claim 1, characterized in that two flow-tapered thin-wall tapered cones are arranged coaxially in the center of the flow-leveling and leveling device opposite the screw hub to prevent a drop in velocity. Geometric spatula blades for spinning flow between cones. 3. An air jet generator as claimed in claim 1 or 2, characterized in that it is a universal single module intended for use in the construction of fixed, demountable and mobile open-ended equipment for the transport of persons in a vertical air stream. 4. An air-jet generator as claimed in any one of claims 1 to 3, wherein the geometric features of the generator design and the compact mutual arrangement of its elements, including the screw motor or its gear units, are mounted coaxially before the device inlet or flow. low velocity zones are determined and optimized by necessarily taking into account all elements of the aerodynamic interaction system operating mode, such as computer modeling techniques or experimental databases.