SU1682605A1 - Turbine guide apparatus - Google Patents

Abstract

The invention relates to turbine engineering and can be used in the design or modernization of turbine guides. The purpose of the invention is to increase efficiency. The output edges of the blades of the guide vane, which are inclined in the tangential direction and in the meridional plane, are made in accordance with the mathematical dependence obtained from the condition of the maximum flow rate of the working medium, in which the flow particles flowing out of the guide vane move in normal planes. to form the blades 3 sludge

Description

The invention relates to turbine engineering and can be used in the design or modernization of turbine guides.

The purpose of the invention is to increase efficiency.

FIG. 1 shows a meridional section of a turbine guide; figure 2 - section aa in figure 1, fig.Z - view along arrow B in figure 1

The guide vane contains curvilinear vanes 1, the output edges 2 of which have a slope in the meridional plane and in the tangential direction. The angle of inclination of the output edges 2 in the meridional plane to the radial direction is equal to E. The meridional angle of inclination of the peripheral bounding surface 3 to the axis 4 of the turbine at the point 5 of its intersection with the output edge 2 is equal to sc. The root radius of the output edge 2 is equal to rk. Peripheral geometric angle of exit profile of the scapula 1 in section

A-A, the normal output edge 2, is equal to the Fire - Angle coordinate of the current point 6 of the output edge 2, located on the radius r, and is equal to and is determined by the given "GlЈD, Hc, a, b, c from the equation

w

J

ABOUT)

tg / arcsin

tg gr.HJt (tg e - tg bp)

1 + tg etg bp

(tg 9n -tgf) cose

fe (r2-r |) + b (r-rk) + (c-tgOln j)

where w is the angular coordinate of the current point of the output edge, for the positive direction of which is taken the direction of rotation of the impeller;

.- peripheral geometric angle of exit of the blade profile in cross section, normal exit edge;

Ј is the angle of inclination of the output edge in the meridional plane to the radial direction, taken as negative

ON 09 Yu O O SP

at an inclination of an edge towards the driving wheel;

The meridional angle of inclination of the peripheral bounding surface to the axis of the turbine at the point of its intersection with the output edge, taken positive when this surface is removed from the axis of the turbine in the direction of the impeller;

g is the current radius of the point of the output edge;

rk is the root radius of the output edge;

a, b, c are constant coefficients determined depending on the distribution law of meridional flow angles along the output edge.

The equation is obtained from the condition of the maximum flow rate of the working medium at the outlet of the turbine guide, the blades of which have a slope in the tangential direction and in the meridional plane. The essence of the maximum condition is that the particles of the flow flowing out of the guiding apparatus move in planes normal to the vane blades.

The guide vane operates as follows.

The flow of working medium passes blades 1 and enters the impeller located behind them (not shown). When the blades are curved in accordance with the equation for the given values of ag.n.p., Ј, & p, rv, a, b, c, the optimal distribution of flow parameters over the height of the flow section behind the guiding device is ensured; a given shape of the meridional section of the flow part, matching the inclination angles of current lines and the inclination angles of the end confining surfaces, which leads to a decrease in end losses and an increase in the efficiency of the turbine stage.

Claims (1)

DETAILED DESCRIPTION OF THE INVENTION A turbine guide apparatus installed in front of the impeller and containing curvilinear blades having a slope in the tangential direction, such that, in order to improve efficiency, the blades have an additional slope in the meridional plane, and - patki is made by the form described by the equation R | (rS-r + bCr-rO + Cc-tgOln., where a) is the angular coordinate of the current point of the output edge, for the positive direction of which the direction of rotation of the impeller is assumed; “Forces - peripheral geometrical angle of the exit profile of the blade in cross section, normal output edge; € is the angle of inclination of the output edge in the meridional plane to the radial direction, taken negative when the edge is inclined towards the impeller; 9P is the meridional angle of inclination of the peripheral bounding surface to the axis of the turbine at its point of intersection with the output edge, taken positive when this surface is removed from the axis of the turbine in the direction of the impeller; g is the current radius of the point of the output edge; Gk - the root radius of the output edge; a, b, c are constant coefficients determined depending on the distribution law of meridional flow corners along the exit edge Aa FIG.