RU34643U1 - Multi-radial turbine - Google Patents

Description

Multinational Radal Turbine

The invention relates to turbine drives with multi-stage speed steps for driving small-sized power units.

Known pneumatic machine with an axial two-stage speed step (see ed. Certificate of the USSR No. 1484630, V24V 23/00, 1989).

The disadvantages of the stage include the complex structure and large aerodynamic energy losses from leakage of the flow into the gaps caused by the three-dimensional gas flow along the axis of the turbine

Multiyear radial turbines are known (see Levenberg VD Ship Turbo Drives, Leningrad, Sudostroenie, 1983, p. 66, Fig. 44), in which the use of several successively placed blade crowns sharply increases the radial size of the stage compared to a multi-shaft axial turbine .

A multi-lifetime radial turbine is known (see German patent X 171297, NYUI 14C, 1906), selected as a prototype, which includes a centrifugal nozzle apparatus and an impeller, which is a disk on which two radial working blade crowns are placed as well as a housing having a portion covering the impeller on the periphery. The gas flow is turned from centrifugal to centripetal direction when it interacts with the inner surface of the indicated section of the housing.

The turbine does not provide a mechanism that directs the flow at the required twist angle to centripetal working crowns, which because of this do not participate in the process of converting the flow energy, but only to a large extent interfere with the exit of the exhaust gas from the stage.

The aerodynamic efficiency of the turbine is also small, because the flow during its rotation is not separated from the cylindrical surface of the impeller disk, which causes large friction losses in the stage.

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MKHFOIDI / IO

These shortcomings are eliminated by the proposed solution. The problem to be solved is the improvement of the design of the multi-walled radial tzfbin.

The technical result is an increase in the aerodynamic efficiency of turbine wheels.

This technical result is achieved by the fact that in a multi-shaft radial turbine containing a centrifugal nozzle apparatus, the impeller is a disk, on the two side surfaces of which there are radial impeller blades, as well as a housing having a section covering the impeller around the periphery, on the inside the surface of the indicated section of the housing opposite the cylindrical surface of the impeller disk is fixed intermediate guide apparatus, made in the form of a crown of axial blades. An annular barrier is fixed on the inner edges of the axial blades of the intermediate guide vane with a gap with respect to the cylindrical surface of the impeller disk.

The proposed solution is shown in the drawings.

FIG. 1 is a longitudinal section of a turbine.

FIG. 2 - an expanded section "aa in figure 1.

The multi-walled radiopaque turbine includes a centrifugal nozzle apparatus 1 (Fig. 1) mounted in the housing and an impeller 2.

On the two sides of the impeller disk 2 there are radial working blade crowns: on the surface facing the nozzle apparatus, centrifugal blade crowns 3 are placed; on the second surface of the indicated disk there are centripetal working vanes 4. The body has a section covering the impeller on the periphery, consisting of conventionally installed elements 5, 6, 7, namely: element 5 is placed opposite the centrifugal working vanes 3, element 7 is placed opposite centripetal scapular working crowns 4;

an element 6 is placed between the NNMs opposite the cylindrical surface of the disk of the impeller 2. An intermediate guide device is fixed on the inner surface of the housing element 6, made in the form of a crown of axial blades 8 (Fig. 2). An annular barrier 9 is fixed on the inner edges of these blades with a gap relative to the cylindrical surface of the impeller disk

The turbine works as follows. The gas flow, acquiring a centrifugal direction of motion at the entrance to the stage, accelerates in the nozzle apparatus 1. Moving further through the centrifugal working vanes 3, the stream transfers part of its kinetic energy to the impeller 2. Passing along the inner surface of the housing element 5, the flow changes direction to axial. Interacting with the crown of axial blades 8 (Fig. 2) of the intermediate guide vane, the flow acquires a twist angle necessary for gasdynamically efficient entry into the centripetal working blade crowns 4. Passing along the inner surface of the housing element 7, the flow changes direction to centripetal. Moving further through the blade crowns 4, the stream transfers the remainder of its kinetic energy to the impeller and exits the stage.

A distinctive feature of a multi-radial turbine is the presence of an intermediate guide vane made in the form of a crown of axial blades 8, which provide an efficient process of converting flow energy into centripetal blade crowns 4. An annular barrier 9 prevents gas leakage outside the crown of the guide vanes 8 and limits the friction of the flow about the cylindrical surface of the impeller 2. The described turbine is gasdynamically significantly more effective than the prototype. The use of an intermediate guide vane does not lead to an increase in the size of the step, since the crown of axial blades 8 is located inside the existing gas channel in the prototype.

Claims (2)

1. A multi-walled radial turbine comprising a centrifugal nozzle apparatus, an impeller representing a disk on which two radial impeller crowns are located on two lateral surfaces, and also a housing having a portion covering the impeller around the periphery, characterized in that on the inner surface of said a section of the housing opposite the cylindrical surface of the impeller disk is fixed intermediate guide apparatus made in the form of a crown of axial blades. 2. The turbine according to claim 1, characterized in that an annular barrier is fixed on the inner edges of the axial blades of the intermediate guide vane with a gap with respect to the cylindrical surface of the impeller disk.