SU861643A1 - Ventilation eqipment - Google Patents

Description

(54) VENTILATION INSTALLATION

one

The invention relates to the means of ventilation used for. airing with free jets and, in particular, to installations for airing open pit mining (quarry).

Known means of ventilation of quarries, based on the use of mine and special jet fans, as well as aircraft. One of the main requirements for an installation for airing quarries is that it must be mobile (1). Therefore, most of the installations are made mobile and equipped with devices for changing the direction of the jet in the horizontal and vertical planes.

However, the design features of the existing technology do not allow the rotation of the jet in the vertical plane within wide limits. As a rule, the jet deviation from the horizontal plane does not exceed 30. Therefore, the installations are divided into two characteristic groups. Some create vertical jets, others slightly inclined and horizontal. This is the first significant drawback of the known installations.

The second significant disadvantage of the known installations results from the inconsistency of the following requirements. Career fans must provide a supply of air flow at the required distance with the highest possible flow rate of air in the jet. In practice, this means that you need to create more powerful installations than the existing ones. On the other hand, they should provide convenience, ease of operation and control. But the more the fan drive is, the harder it is to operate it. Therefore, a further increase in the power of the factory is extremely inexpedient.

The closest technical solution is a fan installation, where two fan units operating in parallel are combined with a swivel tee, which provides opportunities to create a single jet and change the angle of inclination of the jet 25 within wide limits. The installation is capable of creating jets vertical, horizontal and with any practically necessary angle of inclination Gz.

However, the area of the output section 30 of the tee should be no more than the total area of the flow part of the two fans. More precisely, they should be equal (6. On the other hand, it is known that jets with the largest possible initial diameter are the most economical. This result for axisymmetric jets was obtained experimentally (7), and also directly follows from the joint consideration of expressions defining impulse 3 and the energy of the EV output section.

,,

where F and Vp are the nozzle exit area and flow velocity in this section; p is the density of air. The result is a dependency

from which it follows that to obtain a given value of 3 that provides the required range, it is more economical to increase the value (i.e., the area of the nozzle or the initial area of the free flow section.

The aim of the technical solution is to increase the ventilation efficiency by providing the possibility of changing the angle of inclination of the free air stream over a wide range.

This is achieved by the fact that the pipeline is designed as a closed loop with a discontinuous gap, the total length of which is 70-80% of the perimeter of the loop.

FIG. 1 shows a fan installation, on the flow exit side} in FIG. 2 - the contour is turned. by 90.

The ventilation unit consists of two fan units 1, connected by a circuit 2 of the pipeline with a slot 3, a turning mechanism 4 of the circuit of the pipeline 2 with a drive 5. The fan units can be located inside or outside the circuit.

When the fan units are working on a pipeline with a slit forming a contour, a contour turbulent jet is created. As a result, air is drawn into the inner region to obtain a total free flow, the cross-sectional area of which is equal to the area of the contoured gap, including the width of the gap. A change in the angle of inclination of the total air flow is carried out by turning the contour of the pipelines using a turning mechanism. The practical limits of the variation of the angle of inclination of the jet are determined by the specific design. When taken out of the contour of the veins. Tyler gears turn can be made on.

Thus, the solution of the technical problem of connecting two fan units into one unit with

 using the rotary contour provides the ability to change the angle

tilt jet to unlimited limits. The use of a slotted pipe contour as a device for changing the inclination of the jet allows 5 to increase the area of the initial

jet sections, thereby increasing its efficiency. Choosing the appropriate size of the contour, you can increase the initial performance

0 and range at constant

aerodynamic modes of fan units.

The use of the contour allows the aerodynamic parameters of the free jet to be varied within wide limits.

The proposed ventilation installation is recommended to be used for ventilation of mining quarries. Production of 0 units can be carried out by the ore-repair plants, using shaft-mounted fans, manufactured serially.

The use of a slotted conduit contour for changing the angle of inclination of the jet in a single fan installation results in similar technical and positive effects.

Claims (2)

Invention Formula A ventilation unit, including fan units, interconnected by a pipeline, and a turning mechanism, is different from the fact that, in order to increase the ventilation efficiency by providing the possibility of changing the angle of inclination of the free air stream in 0 wide limits, the pipeline is in the form of a closed loop with a discontinuous gap, the total length of which is 70-80% of the perimeter of the loop. 5 Sources of information taken into account during the examination 1. Ushakov K. 3., Mikhailov V. A. Aerologs for quarries. M., Nedra, 1975, p. 248. 2. USSR author's certificate 470639, cl. E 21 F 1/08, 1971. 3 j 4 5