Transition section structure for turbine first-stage moving blade cooling effect test

Abstract

The invention relates to the technical field of gas turbines, and particularly discloses a transition section structure for a turbine first-stage moving blade cooling effect test, which comprises a straight section, a deflection section, a deflection section air inlet end support assembly, a support frame assembly, a hoisting assembly and an elastic sealing piece, the straight section is divided into an inner wall and an outer wall which are welded on a cascade test section cover plate, and the inner wall and the outer wall are connected at the air inlet end through a plurality of supporting frames; the deflection section is divided into an inner wall and an outer wall, two ends of the inner wall and two ends of the outer wall are connected through a plurality of supporting frames, and positioning pins for connecting the inner wall and the outer wall are arranged on the multiple supporting frames at the air inlet end; according to the invention, the transition section guides airflow to smoothly transit from the outlet of the combustion chamber to the inlet of the blade grid test section through turning in the limited space of the test cabin, so that a specific inlet airflow angle is provided for a test blade; the transition section is divided into two sections, and the straight section is welded on the cascade test section to support two ends of the deflection section of the transition section, so that torsional deformation of the deflection section of the transition section is effectively reduced, thermal stress is reduced, and the service life of the transition section is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbines, in particular to a transition section structure for a first-stage turbine moving blade cooling effect test. Background Art

[0002] In order to understand the cooling efficiency characteristics of the first-stage moving blades of gas turbines, blade cooling efficiency test benches are widely used at home and abroad to carry out comprehensive cooling efficiency characteristics tests of moving blades under static conditions. In order to promote the rapid development of gas turbines in my country, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences is responsible for the construction of a high-efficiency and low-carbon gas turbine test device, among which the TB01A station is mainly used to carry out blade cooling efficiency tests under high temperature and high pressure conditions (such as H / J, F class). A test system for the combustion chamber-turbine coupled working characteristics has been established to verify the effectiveness and reliability of the internal cooling structure, coating, and materials of the blades.

[0003] The main structures of the cascade cooling effect test include: upstream section (heater, transition section, front measurement section), cascade test section, downstream section (rear measurement section and exhaust section), etc. The upstream section of the existing moving blade cooling effect test bench generally adopts a straight section structure. In order to make the test chamber applicable to more types of cascade tests with higher parameters, the TB01A test chamber is divided into two sections, front and rear. The exhaust section and cooling spray structure are arranged in the rear cabin, and the heater is arranged outside the front cabin. In order to meet the real incoming flue gas conditions of the turbine blades, the combustion chamber is used to heat the cascade intake air, the main air is passed through the front cabin, and the cascade test section is arranged between the two cabins. In the existing similar designs, the installation angle of the blade casing of the test cabin is adjusted to maintain the straight upstream section structure to achieve the simulation of the inlet airflow angle. However, the TB01A test cabin needs to be modified greatly, and the modification time and cost are high. In order to meet the requirements of the arrangement of the combustion chamber, the cascade test section, and the exhaust section in the test cabin, a compact curved transition section structure is designed, which can convert the axial exhaust of the combustion chamber into a tangential exhaust with a circumferential velocity in the limited space of the front cabin, and provide a suitable inlet airflow angle for the cascade test piece. The working fluid in the transition section has been fully burned and has not expanded to do work. In addition, due to the different relative positions of the combustion chamber outlet and the inlet of the cascade test section and the requirements of the moving blade cooling effect test piece for the inlet airflow angle, the transition section will simultaneously withstand high temperature deformation and high-speed airflow deflection to cause torsional deformation, resulting in deformation and stress of the transition section, and reduced service life. How to effectively reduce the torsional deformation of the transition section is the key to further improving the service life of the transition section for the first-stage turbine moving blade cooling effect test; for this purpose, a transition section structure for the first-stage turbine moving blade cooling effect test is provided. Summary of the invention

[0004] The purpose of the present invention is to provide a transition section structure for the cooling efficiency test of the first stage moving blades of a turbine in view of the defects of the prior art, so as to solve the problems raised by the above-mentioned background technology.

[0005] To achieve the above-mentioned object, the present invention provides the following technical solutions: a transition section structure for a turbine first-stage moving blade cooling efficiency test, comprising a transition section, the transition section comprising a deflection section, a support frame assembly, a hoisting assembly and an elastic sealing sheet connecting the inner walls of the two sections, a straight section and a deflection section inlet end support assembly;

[0006] The support frame assembly is composed of a first deflection section air inlet end support frame, a positioning pin locking gasket I, positioning pins on the inner and outer walls of the air inlet end, a second deflection section air inlet end support frame, a deflection section exhaust end support frame, and a straight section support frame;

[0007] The deflection section air inlet end support assembly is composed of a hoop, a bracket, a hoop nut, a hoop locking washer, an outer wall positioning pin, and a positioning pin locking washer II;

[0008] The straight section comprises a straight section outer wall and a straight section inner wall, the straight section outer wall and the straight section inner wall are connected at the straight section air inlet end by a straight section support frame, and the straight section outer wall and the straight section inner wall are both welded to the cascade test section cover plate at the straight section air outlet end;

[0009] The deflection section comprises an outer wall of the deflection section and an inner wall of the deflection section, a plurality of first deflection section air inlet end support frames and second deflection section air inlet end support frames are uniformly distributed between the outer wall of the deflection section and the inner wall of the deflection section at the air inlet end of the deflection section, the outer wall of the deflection section and the inner wall of the deflection section are connected at the air inlet end of the deflection section through the first deflection section air inlet end support frame and the second deflection section air inlet end support frame, the inner and outer wall positioning pins of the air inlet end are welded inside the second deflection section air inlet end support frame, the outer wall of the air inlet end of the deflection section falls on the bracket, the outer wall positioning pin connected to the outer wall of the deflection section is arranged on the bracket, a hoop surrounding the outer wall of the deflection section is arranged on the bracket, and the inner and outer walls of the deflection section are connected at the exhaust end of the deflection section through the exhaust end support frame of the deflection section;

[0010] An elastic sealing sheet is welded to the inner wall of the deflection section, and the elastic sealing sheet is plugged into the inner wall of the straight section. An axial gap δ5 is reserved between the outer wall of the deflection section and the outer wall of the straight section. Two L-shaped plug-in plates are welded to the outer wall of the transition section and plugged into each other. An axial gap δ6 and a radial gap δ7 are reserved between the two L-shaped plug-in parts, forming a multi-stage seal.

[0011] The lifting assembly includes a rotating pin, a hanger, a lifting lug, a lifting lug locking washer, and a lifting lug nut;

[0012] The lifting lug and the hanger are assembled together through a rotating pin, a lifting lug locking washer and a lifting lug nut to form a lifting assembly, and the lifting assembly is spot welded on the exhaust end of the deflection section of the outer wall of the deflection section;

[0013] A number of air film holes are provided at a, b and f on the risk stress zone of the inner wall of the deflection section and the inner wall of the straight section, which are used to reduce the temperature and stress in the risk zone; a circle of air film holes is provided at e on one side of the weld where the inner wall of the straight section connects the blade test section cover plate, which is used to reduce the temperature gradient of the connecting weld and reduce thermal stress; circular crack-stop holes are provided at g at the four corners of the probe mounting hole on the inner wall of the straight section, which are used to prevent cracks at the four corners of the probe mounting hole.

[0014] As a preferred technical solution of the present invention, the outer wall of the deflection section is welded to the elastic sealing sheet at the air inlet end of the transition section, the elastic sealing sheet at the air inlet end of the transition section is inserted into the guide bushing of the combustion chamber, the flame tube is welded to the elastic sealing sheet at the rear end of the flame tube, and the elastic sealing sheet at the rear end of the flame tube is inserted into the inner wall of the deflection section; the support assembly at the air inlet end of the deflection section is installed on the test cabin by bolts, and a moving blade test piece is provided at one end of the straight section.

[0015] As a preferred technical solution of the present invention, the straight section support frame is welded inside the outer wall of the straight section and is in sliding friction contact with the inner wall of the straight section. The deflection section exhaust end support frame is welded inside the outer wall of the deflection section and is in sliding friction contact with the inner wall of the deflection section.

[0016] As a preferred technical solution of the present invention, the first deflection section air inlet end support frame is welded on the inner wall of the deflection section and is in sliding friction contact with the outer wall of the deflection section; a pad with a threaded hole is welded inside the trapezoidal upper bottom edge of the second deflection section air inlet end support frame, and a positioning pin locking gasket I is provided between the positioning pins on the inner and outer walls of the air inlet end and the pad, the positioning pins on the inner and outer walls of the air inlet end of the deflection section are connected to the pad by threads, and the positioning pins on the inner and outer walls of the air inlet end of the deflection section are deeply inserted into the positioning holes on the outer wall of the deflection section, and deformation gaps are reserved in the axial and radial directions. It is used to prevent the inner wall of the deflection section from torsionally transitioning, and also allows the inner wall of the deflection section to deform axially and radially, thereby reducing the thermal stress of the inner wall of the deflection section; the axial clearance between the inner and outer wall locating pins of the inlet end and the inlet end side wall of the locating hole of the outer wall of the deflection section is δ1, and satisfies 2.8mm≤δ1≤3.2mm, the axial clearance between the inner and outer wall locating pins of the inlet end and the exhaust end side wall of the locating hole of the outer wall of the deflection section is δ2, and satisfies 0.3mm≤δ2≤1mm, and the radial clearance between the inner and outer wall locating pins of the inlet end and the locating hole of the outer wall of the deflection section is δ r , and satisfy 0.3mm≤δ r ≤1mm, δ1 meets the requirement of contact between the inner and outer wall positioning pins of the air inlet end and the positioning holes of the outer wall of the deflection section after maximum thermal deformation, δ2, δ r The size meets the limiting requirements of the positioning hole on the outer wall of the deflection section after thermal deformation on the positioning pins on the inner and outer walls of the air inlet end, and is used to prevent excessive torsional deformation of the inner wall of the deflection section.

[0017] As a preferred technical solution of the present invention, the hanger is fixed to the cover plate of the blade grid test section by bolts, and the axial direction of the hanging assembly is the same as the air intake direction of the transition section inlet.

[0018] As a preferred technical solution of the present invention, a positioning pin locking gasket II is arranged between the outer wall positioning pin and the outer wall of the deflection section, and an axial and radial clearance is reserved between the outer wall positioning pin and the positioning hole of the outer wall of the deflection section. The axial clearance between the outer wall positioning pin and the intake end side wall of the deflection section outer wall positioning hole is δ3, and satisfies 5mm≤δ5≤10mm, the axial clearance between the outer wall positioning pin and the exhaust end side wall of the deflection section outer wall positioning hole is δ4, and satisfies 0.3mm≤δ4≤1mm, and the radial clearance between the outer wall positioning pin and the side wall of the deflection section outer wall positioning hole is δ rr , and satisfy 0.3mm≤δ rr ≤1mm,δ4,δ rr The size meets the limiting requirements of the positioning hole on the outer wall of the deflection section after thermal deformation to the positioning pin on the outer wall, which is used to prevent the outer wall of the deflection section from being excessively deformed; the bracket realizes sliding friction contact with the outer wall of the deflection section through the arc groove, and the hoop is connected to the bracket through the hoop nut and the hoop locking gasket.

[0019] As a preferred technical solution of the present invention, the straight section support frame and the deflection section exhaust end support frame are both trapezoidal structures lacking a bottom edge, and the intersection of the two waists with the bottom edge extends in an arc shape to both sides of the upper bottom edge of the trapezoid. The first deflection section intake end support frame is also a trapezoidal structure lacking a bottom edge, but the intersection of the two waists with the bottom edge extends to both sides along the contour line of the inner wall of the deflection section.

[0020] As a preferred technical solution of the present invention, the axial clearance at the middle section between the outer wall of the straight section and the outer wall of the deflection section is δ5, and satisfies 1.7mm≤δ5≤2.8mm. The axial clearance is sealed by connecting two L-shaped connectors respectively welded on the outer wall of the straight section and the outer wall of the deflection section. The axial clearance δ6 of the two L-shaped connectors is equal to δ5, and the radial clearance is δ7, and satisfies 3.5mm≤δ7≤4.5mm. The sizes of δ5, δ6, and δ7 are sufficient to ensure the sealing performance, and the outer wall of the straight section and the outer wall of the deflection section do not contact each other after thermal deformation.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The transition section structure for the cooling efficiency test of the first-stage turbine blade provided by the present invention guides the airflow to smoothly transition from the combustion chamber outlet to the blade cascade test section inlet in the limited space of the test chamber by turning, thereby providing a specific inlet airflow angle for the first-stage turbine blade inlet, saving modification time and cost;

[0023] (2) The transition section structure for the first-stage turbine blade cooling efficiency test provided by the present invention is divided into a deflection section and a straight section. The straight section provides a specific inlet airflow angle for the blade cascade. The segmentation can avoid excessive cumulative deformation of the transition section blade cascade test section end caused by airflow deflection when the transition section is not segmented;

[0024] (3) The transition section structure for the cooling efficiency test of the first-stage moving blades of the turbine provided by the present invention can effectively transfer the torsional deformation of the inner wall of the deflection section to the support frame and the outer wall of the deflection section by setting a support frame in sliding friction contact with the inner wall between the inner and outer walls of the exhaust end of the deflection section, and setting a support frame in sliding friction contact with the outer wall between the inner and outer walls of the intake end of the deflection section, and setting a positioning pin, and then release the deformation of the outer wall of the deflection section through the rotation of the suspended rotating pair and the sliding deformation along the semicircular groove of the bracket, which can effectively reduce the torsional deformation of the transition section, reduce thermal stress, and extend the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the transition section structure;

[0026] Figure 2 Schematic diagram of the support frame (Figure a is the support frame at the air intake end of the deflection section (with pin holes), Figure b is the support frame at the air intake end of the deflection section, and Figure c is the support frame at the exhaust end of the deflection section and the support frame at the straight section);

[0027] Figure 3 Schematic diagram of the gap between the positioning pin and the outer wall of the deflection section and the outer wall gap (Figure a is the gap between the positioning pin on the inner and outer walls of the air inlet end and the outer wall positioning hole, Figure b is the gap between the positioning pin on the outer wall and the outer wall positioning hole, and Figure c is the gap between the outer wall of the deflection section and the outer wall of the straight section);

[0028] Figure 4 Schematic diagram of support frame distribution (Figure a shows the support frame distribution in the straight section, Figure b shows the support frame distribution at the exhaust end of the deflection section, and the viewing direction is the intake-exhaust direction);

[0029] Figure 5 It is a schematic diagram of the inner wall connection and air film hole distribution of the transition section;

[0030] Figure 6 Schematic diagram of the layout of the transition section, combustion chamber, and cascade test section.

[0031] In the figure: 100, transition section; 2, elastic sealing sheet at the inlet end of transition section; 3, guide bushing; 4, combustion chamber casing; 5, elastic sealing sheet at the tail end of flame tube; 6, flame tube; 7, blade test section cover; 8, moving blade test piece; 110, deflection section; 111, outer wall of deflection section; 112, inner wall of deflection section; 113, inlet end of deflection section; 114, exhaust end of deflection section; 120, support frame assembly; 121, support frame at the inlet end of the first deflection section; 122, positioning pin locking gasket I; 123, positioning pins on the inner and outer walls of the inlet end; 124, support frame at the inlet end of the second deflection section; 125, deflection 1. Exhaust end support frame of the section; 126. Straight section support frame; 130. Lifting assembly; 131. Rotating pin; 132. Hanger; 133. Lifting ear; 134. Lifting ear locking gasket; 135. Lifting ear nut; 140. Elastic sealing sheet; 150. Straight section; 151. Straight section outer wall; 152. Straight section inner wall; 153. Straight section air inlet end; 154. Straight section air outlet end; 160. Deflection section air inlet end support assembly; 161. Hoop; 162. Bracket; 163. Hoop nut; 164. Hoop locking gasket; 165. Outer wall positioning pin; 166. Positioning pin locking gasket II;

[0032] δ1: Axial clearance between the positioning pins on the inner and outer walls of the air inlet end and the positioning hole on the outer wall of the deflection section;

[0033] δ2: Axial clearance between the positioning pins on the inner and outer walls of the air inlet end and the positioning hole on the outer wall of the deflection section on the exhaust end side wall;

[0034] δ r : Radial clearance between the positioning pins on the inner and outer walls of the air inlet end and the positioning holes on the outer wall of the deflection section;

[0035] δ3: Axial clearance between the outer wall positioning pin and the air inlet end side wall of the positioning hole on the outer wall of the deflection section;

[0036] δ4: Axial clearance between the outer wall positioning pin and the exhaust end side wall of the positioning hole on the outer wall of the deflection section;

[0037] δ rr : Radial clearance between the outer wall positioning pin and the outer wall positioning hole of the deflection section;

[0038] δ5: Axial clearance between the outer wall of the deflection section and the straight section;

[0039] δ6: Axial clearance of the outer wall L-shaped connector;

[0040] δ7: radial clearance of the outer wall L-shaped connector;

[0041] a: air film hole Ⅰ on the inner wall of the deflection section; b: air film hole Ⅱ on the inner wall of the deflection section;

[0042] c: air film hole under the lifting ear on the inner wall of the deflection section; d: air film hole under the support frame on the inner wall of the deflection section;

[0043] e: air film hole for weld protection on the inner wall of the straight section; f: air film hole on the inner wall of the straight section;

[0044] g: Crack-stopping hole on the inner wall of the straight section; h: Air film hole under the support frame on the inner wall of the straight section. DETAILED DESCRIPTION

[0045] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0046] Example: See Figure 1 The present invention provides a technical solution: a transition section structure for a turbine first-stage moving blade cooling efficiency test, comprising a transition section 100, the transition section 100 comprising a deflection section 110, a support frame assembly 120, a hoisting assembly 130 and an elastic sealing sheet 140 connecting two sections of the inner wall, a straight section 150 and a deflection section inlet end support assembly 160;

[0047] like Figure 1 As shown, the support frame assembly 120 is composed of a first deflection section air intake end support frame 121, a positioning pin locking gasket I 122, an air intake end inner and outer wall positioning pins 123, a second deflection section air intake end support frame 124, a deflection section exhaust end support frame 125, and a straight section support frame 126;

[0048] like Figure 1 As shown, the deflection section air inlet end support assembly 160 is composed of a hoop 161, a bracket 162, a hoop nut 163, a hoop locking washer 164, an outer wall positioning pin 165, and a positioning pin locking washer II 166;

[0049] like Figure 1 As shown, the straight section 150 includes a straight section outer wall 151 and a straight section inner wall 152, the straight section outer wall 151 and the straight section inner wall 152 are connected at the straight section air inlet end 153 through a straight section support frame 126, and the straight section outer wall 151 and the straight section inner wall 152 are both welded to the cascade test section cover plate 7 at the straight section air outlet end 154;

[0050] like Figure 1As shown, the deflection section 110 includes a deflection section outer wall 111 and a deflection section inner wall 112, and a plurality of first deflection section air inlet end support frames 121 and second deflection section air inlet end support frames 124 are uniformly distributed circumferentially between the deflection section outer wall 111 and the deflection section inner wall 112 at the deflection section air inlet end 113. The deflection section outer wall 111 and the deflection section inner wall 112 are connected at the deflection section air inlet end 113 through the first deflection section air inlet end support frame 121 and the second deflection section air inlet end support frame 124. The support frame 124 is connected, the inner and outer wall positioning pins 123 of the air inlet end of the second deflection section are welded inside the support frame 124 of the air inlet end, the outer wall of the air inlet end 113 of the deflection section falls on the bracket 162, the bracket 162 is provided with an outer wall positioning pin 165 connected with the outer wall 111 of the deflection section, the bracket 162 is provided with a hoop 161 surrounding the outer wall 111 of the deflection section, and the inner and outer walls of the deflection section are connected at the deflection section exhaust end 114 through the deflection section exhaust end support frame 125;

[0051] like Figure 1 As shown, the inner wall 112 of the deflection section is welded with an elastic sealing sheet 140, which is plugged into the inner wall 152 of the straight section. The outer wall 111 of the deflection section and the outer wall 151 of the straight section are provided with a gap δ5 in the axial direction. Two L-shaped plug-in plates are welded to the outer wall of the transition section 100 and plugged into each other. An axial gap δ6 and a radial gap δ7 are reserved between the two L-shaped plug-in parts, forming a multi-stage seal.

[0052] like Figure 1 As shown, the hanging assembly 130 includes a rotating pin 131, a hanger 132, a hanging ear 133, a hanging ear locking washer 134, and a hanging ear nut 135;

[0053] The lifting lug 133 and the hanger 132 are assembled together through a rotating pin 131, a lifting lug locking washer 134 and a lifting lug nut 135 to form a lifting assembly 130, and the lifting assembly 130 is spot welded on the deflection section exhaust end 114 of the deflection section outer wall 111;

[0054] like Figure 5As shown, a plurality of air film holes are arranged at a, b, and f on the risk stress area of ​​the deflection section inner wall 112 and the straight section inner wall 152, which are used to reduce the temperature and stress in the risk area. Air film holes are arranged at the corresponding position c of the lifting ear, and at the positions d and h of the support frame on the deflection section inner wall 112, which are used to reduce the adverse effect of the impact holes reduced on the outer wall of the lifting ear 133, the exhaust end support frame 125 of the deflection section, and the straight section support frame 126 on the inner wall cooling. A circle of air film holes is arranged at e on one side of the weld where the straight section inner wall 152 is connected to the blade test section cover plate 7, which is used to reduce the temperature of the connecting weld. Gradient, reduce thermal stress, and set circular crack-stop holes at g at the four corners of the probe installation hole 152 on the inner wall of the straight section to prevent cracking at the four corners of the probe installation hole; among them, the air film hole at a is the air film hole I on the inner wall of the deflection section; the air film hole at b is the air film hole II on the inner wall of the deflection section; the air film hole at c is the air film hole under the lifting ear on the inner wall of the deflection section; the air film hole at d is the air film hole under the support frame on the inner wall of the deflection section; the air film hole at e is the air film hole for protection of the weld on the inner wall of the straight section; the air film hole at f is the air film hole on the inner wall of the straight section; the hole at g is the crack-stop hole on the inner wall of the straight section; the air film hole at h is the air film hole under the support frame on the inner wall of the straight section.

[0055] like Figure 6 As shown, the outer wall 111 of the deflection section is welded to the elastic sealing sheet 2 at the air inlet end of the transition section, the elastic sealing sheet 2 at the air inlet end of the transition section is inserted into the guide bushing 3 of the combustion chamber, the flame tube 6 is welded to the elastic sealing sheet 5 at the rear end of the flame tube, and the elastic sealing sheet 5 at the rear end of the flame tube is inserted into the inner wall 112 of the deflection section; the deflection section air inlet end support assembly 160 is installed on the test cabin by bolts, and a moving blade test piece 8 is provided at one end of the straight section 150.

[0056] like Figure 1 As shown, the straight section support frame 126 is welded inside the straight section outer wall 151, and is in sliding friction contact with the straight section inner wall 152, which supports the inner and outer walls of the straight section while not hindering the expansion of the straight section inner wall after being heated, thereby reducing the thermal stress of the straight section inner wall. The deflection section exhaust end support frame 125 is welded inside the deflection section outer wall 111, and is in sliding friction contact with the deflection section inner wall 112, so that the deflection section inner wall can achieve a larger axial deformation, reducing thermal stress; more deflection section exhaust end support frames are set on the impact surface of the airflow deflection than other surfaces, so as to absorb and transmit the force of the airflow on the deflection section inner wall.

[0057] like Figure 1 , Figure 2 (a) and Figure 3As shown in (a), the first deflection section air inlet end support frame 121 is welded on the inner wall 112 of the deflection section, and is in sliding friction contact with the outer wall 111 of the deflection section, so that the inner wall of the deflection section can achieve a large axial deformation, reducing thermal stress; a pad with a threaded hole is welded inside the trapezoidal upper bottom edge of the second deflection section air inlet end support frame 124, and a positioning pin locking gasket I 122 is provided between the air inlet end inner and outer wall positioning pins 123 and the pad, and the air inlet end inner and outer wall positioning pins 123 of the deflection section 110 are connected to the pad by threads, and the air inlet end inner and outer wall positioning pins 123 of the deflection section 110 penetrate into the outer wall 111 of the deflection section. In the positioning hole of 1, axial and radial deformation gaps are reserved to prevent the inner wall of the deflection section from torsion, while allowing the inner wall of the deflection section to deform axially and radially, thereby reducing the thermal stress of the inner wall of the deflection section; the axial gap between the inner and outer wall positioning pins 123 of the inlet end and the side wall of the positioning hole of the outer wall of the deflection section is δ1, and satisfies 2.8mm≤δ1≤3.2mm, the axial gap between the inner and outer wall positioning pins 123 of the inlet end and the side wall of the positioning hole of the outer wall of the deflection section is δ2, and satisfies 0.3mm≤δ2≤1mm, and the radial gap between the inner and outer wall positioning pins 123 of the inlet end and the positioning hole of the outer wall of the deflection section is δ r , and satisfy 0.3mm≤δ r ≤1mm, δ1 meets the requirement of contact between the positioning pins 123 on the inner and outer walls of the air inlet end and the positioning holes on the outer wall of the deflection section after maximum thermal deformation, δ2, δ r The size satisfies the limitation requirement of the positioning hole on the outer wall of the deflection section to the positioning pins 123 on the inner and outer walls of the air inlet end after thermal deformation, and is used to prevent excessive torsional deformation of the inner wall of the deflection section.

[0058] like Figure 1 As shown, the hanger 132 is fixed to the blade test section cover 7 by bolts, and the axial direction of the hanging assembly is the same as the air intake direction of the transition section 100. In addition to playing a suspension support role, it can also reduce the force of the inner wall of the deflection section on the outer wall of the deflection section through rotational deformation.

[0059] like Figure 1 and Figure 3 As shown in (b), a positioning pin locking gasket II 166 is provided between the outer wall positioning pin 165 and the deflection section outer wall 111, and axial and radial clearances are reserved between the outer wall positioning pin 165 and the positioning hole of the deflection section outer wall 111. The axial clearance between the outer wall positioning pin 165 and the intake end side wall of the positioning hole of the deflection section outer wall 111 is δ3, and satisfies 5mm≤δ5≤10mm. The axial clearance between the outer wall positioning pin 165 and the exhaust end side wall of the positioning hole of the deflection section outer wall 111 is δ4, and satisfies 0.3mm≤δ4≤1mm. The radial clearance between the outer wall positioning pin 165 and the side wall of the positioning hole of the deflection section outer wall 111 is δ rr , and satisfy 0.3mm≤δ rr ≤1mm,δ4,δ rrThe size meets the limiting requirements of the positioning hole on the outer wall of the deflection section after thermal deformation and the positioning pin on the outer wall, which is used to prevent the outer wall of the deflection section from being excessively deformed; the bracket 162 realizes sliding friction contact with the outer wall 111 of the deflection section through the arc groove, and the hoop 161 is connected to the bracket 162 through the hoop nut 163 and the hoop locking gasket 164.

[0060] like Figure 2 (b) and Figure 2 As shown in (c), the straight section support frame 126 and the deflection section exhaust end support frame 125 are both trapezoidal structures lacking a bottom edge, and the intersection of the two waists with the bottom edge extends in an arc shape to both sides of the upper bottom edge of the trapezoid. The first deflection section intake end support frame 121 is also a trapezoidal structure lacking a bottom edge, but the intersection of the two waists with the bottom edge extends to both sides along the contour line of the inner wall of the deflection section.

[0061] Figure 3 As shown in (c), the axial clearance at the middle section between the straight section outer wall 151 and the deflection section outer wall 111 is δ5, and satisfies 1.7mm≤δ5≤2.8mm. The axial clearance is sealed by connecting two L-shaped connectors respectively welded on the straight section outer wall 151 and the deflection section outer wall 111. The axial clearance δ6 of the two L-shaped connectors is equal to δ5. The radial clearance is δ7, and satisfies 3.5mm≤δ7≤4.5mm. The sizes of δ5, δ6, and δ7 are sufficient to ensure the sealing performance. Under the premise of ensuring the sealing performance, the straight section outer wall and the deflection section outer wall are not in contact after thermal deformation.

[0062] Assembly process: A transition section structure for the first stage turbine blade cooling test, reference Figure 4 As shown in FIG. 1 , first, the straight section support frame 126 is welded inside the straight section outer wall 151, and the straight section outer wall 151 and the straight section inner wall 152 are welded to the cascade test section cover plate 7 to complete the installation of the transition section straight section; Figure 2 As shown in a, the pad with screw holes is welded into the second deflection section intake end support frame 124; Figure 1 After trial-fitting and positioning the inner and outer walls of the deflection section, the second deflection section air inlet end support frame 124, and the air inlet end inner and outer wall positioning pins 123, ensure the positioning pin clearance, first weld one side of the trapezoidal lower bottom side of the first deflection section air inlet end support frame 121 and the second deflection section air inlet end support frame 124 to the deflection section inner wall 112, and then push the other side of the trapezoidal lower bottom side of the support frame to make the trapezoidal upper bottom side of the support frame completely contact with the inner contour of the deflection section outer wall 111, and then weld the remaining side of the trapezoidal lower bottom side of the support frame. After complete contact, the deformation of the air inlet end of the deflection section inner wall 112 can be fully unloaded to the first deflection section air inlet end support frame 121, the second deflection section air inlet end support frame 124 and the deflection section outer wall 111; then install the locking positioning pin locking gasket Ⅰ122 and the air inlet end inner and outer wall positioning pins 123;

[0063] refer to Figure 1 , after trial assembling the bracket 162, the deflection section 110 and the outer wall locating pin 165, ensure the locating pin clearance, lock the locating pin locking gasket II 166 and the outer wall locating pin 165, and install the hoop 161 on the bracket 162 through the hoop nut 163 and the hoop locking gasket 164; the lifting assembly 130 is provided with two groups, first assemble the lifting ear 133, the hanger 132, the rotating pin shaft 131, the lifting ear locking gasket 134, and the lifting ear nut 135 together, and then spot weld the lifting assembly 130 on the exhaust end of the deflection section outer wall 111, assemble the deflection section inner wall 112 into the straight section inner wall 152, and after the combustion chamber and the cascade test section are properly trial assembled, formally weld the connecting weld between the lifting ear 133 and the deflection section outer wall 111, and then lock the lifting ear nut 135 and the lifting ear locking gasket 134.

[0064] refer to Figure 6 As shown, the outer wall 111 of the deflection section is welded with the elastic sealing sheet 2 at the inlet end of the transition section, and then plugged into the combustion chamber guide bushing 3. The flame tube 6 is welded with the elastic sealing sheet 5 at the tail end of the flame tube, and then plugged into the inner wall 112 of the deflection section; the inner and outer walls of the straight section 150 are welded to the cascade test section cover plate 7. The cascade test section cover plate 7 is partially made of high-temperature alloy, which belongs to the same category as the material of the inner wall of the transition section, so as to avoid arranging dissimilar material connection welds in the area with large temperature gradient; the deflection section inlet end support assembly 160 is installed on the test cabin by bolts;

[0065] The straight section support frame is welded inside the outer wall of the straight section and is in sliding friction contact with the inner wall of the straight section. It supports the inner and outer walls of the straight section while not hindering the expansion of the inner wall of the straight section after being heated, thereby reducing the thermal stress of the inner wall of the straight section; the exhaust end support frame of the deflection section is welded inside the outer wall of the deflection section and is in sliding friction contact with the inner wall of the deflection section, so that the inner wall of the deflection section can achieve a larger axial deformation; the air intake end support frame of the deflection section is welded on the inner wall of the deflection section and is in sliding friction contact with the outer wall of the deflection section, so that the inner and outer walls of the deflection section form staggered constraints, thereby improving the stability of the inner and outer walls of the deflection section; more exhaust end support frames of the deflection section are set on the impact surface of the airflow deflection than other surfaces to absorb and transmit the force of the airflow on the inner wall of the deflection section; the axial direction of the hoisting assembly is the same as the air intake direction of the transition section inlet, so in addition to playing a suspension support role, it can also reduce the force of the inner wall of the deflection section on the outer wall of the deflection section through rotational deformation.

[0066] Extract the fluid domain of the deflection section 110 and the straight section 150, couple the solid structure to perform thermal fluid-solid coupling calculation, transfer the temperature and pressure data of the fluid calculation to the solid, set the boundary conditions such as contact and constraint for the solid structure, and calculate the thermal deformation and thermal stress of the transition section. According to the thermal deformation results, adjust the gap of each positioning pin and the gap of the outer wall at the segment, and adjust the number and position of the exhaust end support frame 125 of the deflection section and the support frame 126 of the straight section, such as Figure 4As shown, more support frames are arranged on the right wall and upper and lower walls of the deflection section 110 where the airflow impacts the exhaust end. According to the thermal stress and strain results, the risk zone structure is adjusted, especially according to the calculation results of the thermal stress, the arrangement of the air film holes on the inner wall of the front and rear sections is adjusted, such as Figure 5 As shown, air film holes are set in the risk stress zone of the inner wall at positions a, b, and f to reduce the temperature and stress in the risk zone; air film holes are set at the inner wall corresponding to the ear position c and the support frame positions d and h to reduce the adverse effect of the impact holes reduced on the outer wall of the ear 133 and the support frame on the cooling of the inner wall; a circle of air film holes is set at position e in front of the weld connecting the inner wall 152 of the straight section and the cover plate 7 of the blade test section to reduce the temperature gradient of the connecting weld here and reduce thermal stress; circular crack-stop holes are set at positions g at the four corners of the probe mounting hole to prevent cracks at the four corners of the probe mounting hole.

[0067] The above embodiments only express the implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A transition section structure for a turbine first stage moving blade cooling efficiency test, comprising a transition section (100), characterized in that: The transition section (100) comprises a deflection section (110), a support frame assembly (120), a hanging assembly (130), an elastic sealing sheet (140) connecting the inner walls of the two sections, a straight section (150) and a deflection section air inlet end support assembly (160); The support frame assembly (120) is composed of a first deflection section air intake end support frame (121), a positioning pin locking gasket I (122), air intake end inner and outer wall positioning pins (123), a second deflection section air intake end support frame (124), a deflection section exhaust end support frame (125), and a straight section support frame (126); The deflection section air inlet end support assembly (160) is composed of a hoop (161), a bracket (162), a hoop nut (163), a hoop locking washer (164), an outer wall positioning pin (165), and a positioning pin locking washer II (166); The straight section (150) comprises a straight section outer wall (151) and a straight section inner wall (152); the straight section outer wall (151) and the straight section inner wall (152) are connected at the straight section air inlet end (153) via a straight section support frame (126); and the straight section outer wall (151) and the straight section inner wall (152) are both welded to a cascade test section cover plate (7) at the straight section air outlet end (154); The deflection section (110) comprises a deflection section outer wall (111) and a deflection section inner wall (112); a plurality of first deflection section air inlet end support frames (121) and second deflection section air inlet end support frames (124) are evenly distributed in the circumferential direction at the deflection section air inlet end (113) between the deflection section outer wall (111) and the deflection section inner wall (112); the deflection section outer wall (111) and the deflection section inner wall (112) are connected at the deflection section air inlet end (113) by the first deflection section air inlet end support frame (121) and the second deflection section air inlet end support frame (124); The second deflection section air inlet end support frame (124) is connected, the air inlet end inner and outer wall positioning pins (123) are welded inside the second deflection section air inlet end support frame (124), the outer wall of the deflection section air inlet end (113) falls on the bracket (162), the bracket (162) is provided with an outer wall positioning pin (165) connected to the deflection section outer wall (111), the bracket (162) is provided with a hoop (161) surrounding the deflection section outer wall (111), and the inner and outer walls of the deflection section are connected at the deflection section exhaust end (114) through the deflection section exhaust end support frame (125); An elastic sealing sheet (140) is welded to the inner wall (112) of the deflection section, and the elastic sealing sheet (140) is plugged into the inner wall (152) of the straight section. A gap δ5 is reserved in the axial direction between the outer wall (111) of the deflection section and the outer wall (151) of the straight section. Two L-shaped plug-in plates are welded to the outer wall of the transition section (100) and plugged into each other. An axial gap δ6 and a radial gap δ7 are reserved between the two L-shaped plug-in parts, thereby forming a multi-stage seal. The hanging assembly (130) comprises a rotating pin (131), a hanger (132), a hanging ear (133), a hanging ear locking washer (134), and a hanging ear nut (135); The lifting lug (133) and the hanger (132) are assembled together through a rotating pin (131), a lifting lug locking washer (134) and a lifting lug nut (135) to form a lifting assembly (130), and the lifting assembly (130) is spot welded on the deflection section exhaust end (114) of the deflection section outer wall (111); A plurality of air film holes are arranged at positions a, b and f on the risk stress zone of the deflection section inner wall (112) and the straight section inner wall (152) for reducing the temperature and stress in the risk zone; air film holes are arranged at the position c corresponding to the lifting ear on the deflection section inner wall (112), at the position d of the deflection section exhaust end support frame (125) and at the position h of the straight section support frame (126) for reducing the adverse effect of the impact holes reduced on the inner wall cooling at the lifting ear (133), the deflection section exhaust end support frame (125) and the straight section support frame (126); a circle of air film holes is arranged at position e on one side of the weld where the straight section inner wall (152) is connected to the blade grid test section cover (7) for reducing the temperature gradient of the connecting weld and reducing thermal stress; circular crack stop holes are arranged at positions g at the four corners of the probe installation hole on the straight section inner wall (152) for preventing the four corners of the probe installation hole from cracking.

2. The transition section structure for the turbine first stage moving blade cooling efficiency test according to claim 1 is characterized in that: The outer wall (111) of the deflection section is welded to the elastic sealing sheet (2) at the air inlet end of the transition section, and the elastic sealing sheet (2) at the air inlet end of the transition section is inserted into the guide bushing (3) of the combustion chamber. The flame tube (6) is welded to the elastic sealing sheet (5) at the rear end of the flame tube, and the elastic sealing sheet (5) at the rear end of the flame tube is inserted into the inner wall (112) of the deflection section. The deflection section air inlet end support assembly (160) is installed on the test cabin by bolts, and a moving blade test piece (8) is provided at one end of the straight section (150).

3. The transition section structure for the turbine first stage moving blade cooling efficiency test according to claim 1 is characterized in that: The straight section support frame (126) is welded inside the straight section outer wall (151) and is in sliding friction contact with the straight section inner wall (152); the deflection section exhaust end support frame (125) is welded inside the deflection section outer wall (111), and the deflection section exhaust end support frame (125) is in sliding friction contact with the deflection section inner wall (112).

4. The transition section structure for the turbine first stage moving blade cooling efficiency test according to claim 1 is characterized in that: The first deflection section air inlet end support frame (121) is welded to the deflection section inner wall (112), and the first deflection section air inlet end support frame (121) is in sliding friction contact with the deflection section outer wall (111); a pad with a threaded hole is welded inside the trapezoidal upper bottom edge of the second deflection section air inlet end support frame (124), and a positioning pin locking gasket I (122) is provided between the air inlet end inner and outer wall positioning pins (123) and the pad; the air inlet end inner and outer wall positioning pins (123) of the deflection section (110) are connected to the pad by threads, and the air inlet end inner and outer wall positioning pins (123) of the deflection section (110) penetrate into the deflection section outer wall (111). 11), axial and radial deformation gaps are reserved in the positioning hole to prevent the inner wall of the deflection section from excessive torsion, while also allowing the inner wall of the deflection section to deform axially and radially, thereby reducing the thermal stress of the inner wall of the deflection section; the axial gap between the inner and outer wall positioning pins (123) at the air inlet end and the side wall of the positioning hole at the outer wall of the deflection section is δ1, and satisfies 2.8mm≤δ1≤3.2mm; the axial gap between the inner and outer wall positioning pins (123) at the air inlet end and the side wall of the positioning hole at the exhaust end is δ2, and satisfies 0.3mm≤δ2≤1mm; the radial gap between the inner and outer wall positioning pins (123) at the air inlet end and the positioning hole at the outer wall of the deflection section is δ r , and satisfy 0.3mm≤δ r ≤1mm, δ1 satisfies the requirement that the positioning pins (123) on the inner and outer walls of the air inlet end and the positioning holes on the outer wall of the deflection section are in contact after maximum thermal deformation, δ2, δ r The size satisfies the limitation requirement of the positioning hole on the outer wall of the deflection section to the positioning pin (123) on the inner and outer walls of the air inlet end after thermal deformation, and is used to prevent the inner wall of the deflection section from generating excessive torsional deformation.

5. The transition section structure for the turbine first stage moving blade cooling efficiency test according to claim 1 is characterized in that: The hanger (132) is fixed to the blade cascade test section cover plate (7) by means of bolts, and the axial direction of the hanging assembly is the same as the air intake direction of the transition section (100).

6. The transition section structure for the turbine first stage moving blade cooling efficiency test according to claim 1 is characterized in that: A positioning pin locking gasket II (166) is provided between the outer wall positioning pin (165) and the deflection section outer wall (111); axial and radial clearances are reserved between the outer wall positioning pin (165) and the positioning hole of the deflection section outer wall (111); the axial clearance between the outer wall positioning pin (165) and the air inlet end side wall of the deflection section outer wall (111) positioning hole is δ3, and satisfies 5mm≤δ5≤10mm; the axial clearance between the outer wall positioning pin (165) and the exhaust end side wall of the deflection section outer wall (111) positioning hole is δ4, and satisfies 0.3mm≤δ4≤1mm; the radial clearance between the outer wall positioning pin (165) and the side wall of the deflection section outer wall (111) positioning hole is δ rr , and satisfy 0.3mm≤δ rr ≤1mm,δ4,δ rr The size meets the limiting requirement of the positioning hole on the outer wall of the deflection section after thermal deformation to the positioning pin on the outer wall, and is used to prevent the outer wall of the deflection section from being excessively deformed; the bracket (162) is in sliding friction contact with the outer wall (111) of the deflection section through the circular arc groove, and the hoop (161) is connected to the bracket (162) through the hoop nut (163) and the hoop locking gasket (164).

7. The transition section structure for the turbine first stage moving blade cooling efficiency test according to claim 1 is characterized in that: The straight section support frame (126) and the deflection section exhaust end support frame (125) are both trapezoidal structures lacking a bottom edge, and the intersection of the two waists with the bottom edge extends in an arc shape to both sides of the upper bottom edge of the trapezoid. The first deflection section intake end support frame (121) is also a trapezoidal structure lacking a bottom edge, but the intersection of the two waists with the bottom edge extends to both sides along the contour line of the inner wall of the deflection section.

8. The transition section structure for the turbine first stage moving blade cooling efficiency test according to claim 1 is characterized in that: The axial clearance at the middle section between the straight section outer wall (151) and the deflection section outer wall (111) is δ5 and satisfies 1.7mm≤δ5≤2.8mm. The axial clearance is sealed by plugging two L-shaped connectors respectively welded to the straight section outer wall (151) and the deflection section outer wall (111). The axial clearance δ6 of the two L-shaped connectors is equal to δ5. The radial clearance is δ7 and satisfies 3.5mm≤δ7≤4.5mm. The sizes of δ5, δ6 and δ7 are such that the straight section outer wall and the deflection section outer wall do not contact each other after thermal deformation, while ensuring the sealing performance.

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