CN202756162U - Mixed-flow water turbine adopting novel guide vane and runner blade molded lines - Google Patents

Abstract

The utility model belongs to the technical field of fluid machinery and engineering equipment, in particular to a mixed-flow water turbine, in particular to a mixed-flow water turbine adopting novel guide vanes and runner blade profiles. The water turbine includes a volute, a fixed guide vane, a movable guide vane, a runner and a draft tube. The baffle at the nose end of the volute is an arc-shaped baffle with a radius of 400~420mm; the movable guide vane is a negative curvature guide vane, and both the movable guide vane and the turbine blade adopt new profiles; the cone angle of the straight cone section of the draft tube is θ is 17.5~20o. The water turbine of the utility model improves efficiency, reduces vibration and pressure pulsation, increases the mechanical strength of the runner, reduces the dynamic stress of the runner blade, greatly reduces the probability of cracks in the runner blade, and improves the operation stability of the turbine .

Description

A Francis turbine with new guide vane and runner blade profiles

technical field

The utility model belongs to the technical field of fluid machinery and engineering equipment, and particularly relates to a Francis water turbine, in particular to a Francis water turbine adopting a new guide vane profile and runner blade thickness distribution rules. the

Background technique

For the Francis turbine unit with a water head section of 200m, there are various forms of flow passages. Due to the high operating water head, the current common defects of this type of water turbine unit are poor operational stability, large vibration and pressure fluctuations, and large dynamic stress on the runner blades, which can easily cause cracks in the runner blades. the

Contents of the invention

The purpose of the utility model is to propose a high-stability mixed-flow water turbine which adopts new guide vanes and runner blade profiles. the

The technical scheme of the utility model is:

The structure of the turbine includes volute, fixed guide vane, movable guide vane, runner and draft tube. The upper crown of the wheel is coaxial with the lower ring of the runner,

The baffle at the nose end of the volute is an arc-shaped baffle with a radius of 400-420mm;

The movable guide vane is a negative curvature guide vane, and the coordinates of 23 points on the guide vane profile line in the Cartesian coordinate system are shown in Table 1:

Table 1: Coordinate points of guide vane intermediate section line

serial number 301 302 303 304 305 306 307 308 309 310 311 312 x 0 6 12 18 twenty four 30 36 42 48 54 60 65.71 Y 5.25 4.58 3.9 3.43 3.03 2.81 2.69 2.59 2.4 2.19 1.98 1.86 serial number 313 314 315 316 317 318 319 320 321 322 323 the x 6 12 18 twenty four 30 36 42 48 54 60 65.71 the Y -0.71 -2.17 -3.17 -3.95 -4.5 -4.37 -3.67 -2.81 -1.72 -0.6 -0.9 the

It is 150～175mm that the distance h between the highest point of the upper crown of the runner contacting with the turbine blade to the corresponding highest point of the lower ring of the runner and the turbine blade is 150～175mm;

The coordinates of 23 points on the middle section profile line of the turbine blade in the Cartesian coordinate system are as shown in Table 2:

Table 2: Coordinate points of the profile line of the middle section of the turbine blade

serial number 701 702 703 704 705 706 707 708 709 710 x -81.61 -65.42 -48.8 -32.27 -14.9 0 14.9 32.27 48.84 65.42 Y 32.5 23.99 10.05 0.63 -6.57 -10.51 -12.25 -12.41 -10.31 -6.1 serial number 711 712 713 714 715 716 717 718 719 720 x 80.05 90.56 90.56 80.05 65.42 48.84 32.27 14.9 0 -14.9 Y 1.46 7.11 6.45 -0.63 -7.41 -12.81 -15.40 -15.2 -14.48 -11.42 serial number 721 722 723 the the the the the the the x -32.27 -48.8 -65.42 the the the the the the the Y -7.88 -0.81 10.9 the the the the the the the

The height H between the centerline of the movable guide vane and the bottom plate of the draft tube is 1750~1770mm;

The cone angle θ of the straight cone section of the draft tube is 17.5~20o. the

The beneficial effects of the utility model are: compared with other existing mixed-flow units in the 200m water head section, the efficiency of the water turbine is improved, the vibration and pressure pulsation are reduced, the mechanical strength of the runner is increased, and the dynamic stress of the runner blades is reduced. The probability of cracks in the runner blades is greatly reduced, and the operation stability of the water turbine is improved. the

Description of drawings

Fig. 1 is the schematic diagram of Francis turbine structure;

Fig. 2 is the structural diagram of the Francis turbine runner;

Fig. 3 is the arrangement drawing of fixed guide vane and movable guide vane of water turbine;

Fig. 4 is a schematic diagram of the structure of the volute tongue;

Fig. 5 is the shape schematic diagram of movable guide vane;

Figure 6 is a schematic diagram of the middle section of the runner blade;

Figure 7 is a schematic diagram of the structure of the tailwater cone;

Labels in the figure:

1-volute; 2-fixed guide vane; 3-movable guide vane; 4-turbine runner; 5-draft tube;

6-the lower ring of the runner; 7-the turbine blade; 8-the upper crown of the runner. the

Detailed ways

The utility model provides a mixed-flow water turbine adopting a novel guide vane and runner blade profiles. The utility model will be further described below in conjunction with the accompanying drawings and specific implementation methods. the

As shown in FIG. 1 , the water turbine includes a volute 1 , a fixed guide vane 2 , a movable guide vane 3 , a turbine runner 4 and a draft tube 5 . the

As shown in Figure 2, the structure of the water turbine runner 4 is: a number of water turbine blades 7 are installed on the side of the upper runner crown 8, and a runner lower ring coaxial with the runner crown 8 is installed at the lower end of the water turbine blades 7. 6. the

As shown in Figure 4, the nose end of the volute is changed to an arc-shaped baffle with a radius R of 400-420mm;

As shown in Figure 3 and Figure 5, the middle section of the movable guide vane 3 is designed as a brand-new profile line, which is a closed curve composed of two curves connected end to end, and 23 points are taken from the profile line , the position of each point in the Cartesian coordinate system is shown in Table 1:

Table 1: Coordinate points of guide vane intermediate section line

serial number 301 302 303 304 305 306 307 308 309 310 311 312 x 0 6 12 18 twenty four 30 36 42 48 54 60 65.71 Y 5.25 4.58 3.9 3.43 3.03 2.81 2.69 2.59 2.4 2.19 1.98 1.86 serial number 313 314 315 316 317 318 319 320 321 322 323 the x 6 12 18 twenty four 30 36 42 48 54 60 65.71 the Y -0.71 -2.17 -3.17 -3.95 -4.5 -4.37 -3.67 -2.81 -1.72 -0.6 -0.9 the

The equations of the two curves after fitting are:

y=-0.00002x ³ +0.0027x ² -0.1453x+5.2856;

y=-0.0001x ³ +0.0193x ² -0.7595x+4.5109.

As shown in Figure 2 and Figure 6, in order to ensure the hydraulic performance and structural strength of the runner, the middle section of the turbine blade 7 is designed as a closed curve composed of two end-to-end curves, and 23 points are taken from the profile line, The positions of each point in the Cartesian coordinate system are shown in Table 2:

Table 2: Coordinate points of the profile line of the middle section of the turbine blade

serial number 701 702 703 704 705 706 707 708 709 710 x -81.61 -65.42 -48.8 -32.27 -14.9 0 14.9 32.27 48.84 65.42 Y 32.5 23.99 10.05 0.63 -6.57 -10.51 -12.25 -12.41 -10.31 -6.1 serial number 711 712 713 714 715 716 717 718 719 720 x 80.05 90.56 90.56 80.05 65.42 48.84 32.27 14.9 0 -14.9 Y 1.46 7.11 6.45 -0.63 -7.41 -12.81 -15.40 -15.2 -14.48 -11.42 serial number 721 722 723 the the the the the the the x -32.27 -48.8 -65.42 the the the the the the the Y -7.88 -0.81 10.9 the the the the the the the

The equations of the two curves after fitting are:

y=0.000005x ³ +0.0042x ² -0.2256x-10.18,

y=0.000002x ³ +0.0039x ² -0.1346x-15.056.

As shown in Figure 1, the height of the draft tube is changed so that the height H from the centerline of the movable guide vane 3 to the bottom plate of the draft tube 5 is 1750-1770 mm. the

As shown in Figure 1 and Figure 7, the cone angle θ of the straight cone section of the draft tube 5 is changed to 17.5~20o. the

The utility model is tested on the HLY153-41.5 mixed flow turbine, the flow loss of each part of the flow channel is analyzed, the influence of the shape change of the flow channel on the energy performance, cavitation performance and stability is analyzed, and the different operating conditions are analyzed. condition of hydraulic performance. Through test data and actual effects, it can be found that compared with other existing units, the unit using the utility model has improved efficiency, reduced vibration and pressure pulsation, increased the mechanical strength of the runner, and reduced the dynamic stress of the runner blades. The probability of cracks in the blades of the runner is greatly reduced, and the operation stability of the water turbine is improved. the

Claims (1)

1. one kind is adopted novel guiding blade and runner bucket molded line Francis turbine, comprise spiral case (1), fixed guide vane (2), movable guide vane (3), runner (4) and draft tube (5), the structure of runner (4) is: several turbine blades (7) are installed in the side of the runner crown on top (8), the runner lower ring (6) coaxial with runner crown (8) installed in lower end at turbine blade (7), it is characterized in that

The nose cut water baffle plate of described spiral case (1) is the curved baffle of radius 400～420mm;

Described movable guide vane (3) is the negative cruvature stator, and the coordinate of 23 points in rectangular coordinate system is as shown in table 1 on its Guide vane profile:

Table 1: stator intermediate cross-section profile coordinate point

Sequence number 301 302 303 304 305 306 307 308 309 310 311 312 X 0 6 12 18 24 30 36 42 48 54 60 65.71 Y 5.25 4.58 3.9 3.43 3.03 2.81 2.69 2.59 2.4 2.19 1.98 1.86 Sequence number 313 314 315 316 317 318 319 320 321 322 323 X 6 12 18 24 30 36 42 48 54 60 65.71 Y -0.71 -2.17 -3.17 -3.95 -4.5 -4.37 -3.67 -2.81 -1.72 -0.6 -0.9

Described runner crown (8) and the contacted peak of turbine blade (7) are 150～175mm to the distance h between the corresponding peak of described runner lower ring (6) and turbine blade (7);

The coordinate of 23 points in rectangular coordinate system on the intermediate cross-section molded line of described turbine blade (7) is as shown in table 2:

Table 2: turbine blade intermediate cross-section profile coordinate point

Sequence number 701 702 703 704 705 706 707 708 709 710 X -81.61 -65.42 -48.8 -32.27 -14.9 0 14.9 32.27 48.84 65.42 Y 32.5 23.99 10.05 0.63 -6.57 -10.51 -12.25 -12.41 -10.31 -6.1 Sequence number 711 712 713 714 715 716 717 718 719 720 X 80.05 90.56 90.56 80.05 65.42 48.84 32.27 14.9 0 -14.9 Y 1.46 7.11 6.45 -0.63 -7.41 -12.81 -15.40 -15.2 -14.48 -11.42 Sequence number 721 722 723 X -32.27 -48.8 -65.42 Y -7.88 -0.81 10.9

Described movable guide vane (3) center line is 1750～1770mm to the height H between draft tube (5) base plate;

The taper angle theta of described draft tube (5) right cone section is 17.5～20 °.

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