A device system and method for testing the cooling effect of gas turbine blades

Abstract

The present invention relates to a device system and method for testing the cooling effect of gas turbine blades, the device system comprising a combustion power generation unit, an air cooling unit, a test unit and a water cooling unit; the outlet of the combustion chamber in the combustion power generation unit is connected to the test unit; the outlet of the compressor in the combustion power generation unit is connected to the air cooling unit; the outlet of the air cooling unit is connected to the test unit; the outlet of the water cooling unit is respectively connected to the test unit and the combustion power generation unit; the outlet of the test unit is connected to the combustion power generation unit. The method adopts the device system, uses the combustion chamber gas as the mainstream gas, and uses the compressor air as the cooling air to conduct a turbine blade cooling effect test. The device system provided by the present invention has a simple structure, reduces the equipment purchase cost and power consumption cost of the test device, and can be used to conduct full-temperature, full-pressure and full-scale tests of turbine static blades and moving blades, with high energy utilization efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbines, and in particular to a device system and method for testing the cooling effect of turbine blades of a gas turbine. Background Art

[0002] Turbine blade cooling design technology is a key technology for gas turbines. It is the core technology for increasing the turbine inlet temperature, improving the efficiency of gas turbines, extending the service life of hot end components, and ensuring the long-term stable and safe operation of gas turbines.

[0003] International heavy-duty advanced gas turbines are constantly developing in the direction of high parameters, high performance and low pollution, with the focus on further providing higher turbine inlet temperatures and actively developing more advanced high-temperature materials and cooling technologies. Conducting full-temperature, full-pressure and full-size cooling effect verification tests for newly designed and processed turbine blades is an important part of gas turbine development.

[0004] As the turbine inlet temperature continues to increase, the existing test benches can hardly meet the needs of full-temperature, full-pressure and full-scale testing of advanced gas turbines, and additional systems or equipment such as test fuel supply systems, test combustion chambers, air electric heaters, mainstream air compressors, cooling air compressors and air electric heaters are required. The equipment purchase costs and electricity consumption costs are greatly increased, and the energy utilization rate is low.

[0005] CN105588712A discloses a turbine blade cooling effect test device and method using gas turbine compressor extraction. The device extracts the exhaust gas of the compressor as mainstream air and burns it to form mainstream combustion gas. It is necessary to set up a fuel supply system and a test combustion chamber. The equipment purchase cost is relatively expensive, which is not conducive to the economic efficiency of production.

[0006] CN213985690U discloses a gas turbine combustion and turbine comprehensive cooling effect test system, which requires that the main air and fuel be mixed and burned in the combustion test section to produce high-temperature and high-pressure gas, and needs to simulate the actual working environment of the combustion chamber when the gas turbine is running, and obtain the blade cooling effect by measuring the gas, cold air parameters and the outer surface wall temperature of the blade. The test system has a complex structure, a relatively large investment cost, low energy utilization, and increased electricity consumption.

[0007] Therefore, it is of great economic and practical value to develop a device system and method for testing the cooling effect of turbine blades that meets the requirements of full-temperature, full-pressure and full-scale testing of gas turbines and has a simple structure and low cost. Summary of the invention

[0008] In view of the above problems, the purpose of the present invention is to provide a device system and method for testing the cooling effect of gas turbine turbine blades. Compared with the prior art, the device system provided by the present invention not only has test parameters that meet actual operating conditions, but also can reduce the investment in test equipment, reduce pollution emissions generated by the test, improve energy utilization efficiency, and reduce the impact of the test on the gas turbine power.

[0009] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a device system for testing the cooling effect of gas turbine turbine blades, the device system comprising a combustion power generation unit, an air cooling unit, a test unit and a water cooling unit; the outlet of the combustion chamber in the combustion power generation unit is connected to the test unit; the outlet of the compressor in the combustion power generation unit is connected to the air cooling unit; the outlet of the air cooling unit is connected to the test unit; the outlet of the water cooling unit is respectively connected to the test unit and the combustion power generation unit; and the outlet of the test unit is connected to the combustion power generation unit.

[0011] In the present invention, a high-parameter full-temperature, full-pressure, and full-size turbine blade cooling effect test can be realized through the cooperation of the combustion power generation unit, the air cooling unit, the test unit, and the water cooling unit. For example, the test is carried out under the conditions that the temperature reaches 1500°C, the pressure reaches 2.3MPa, and the turbine blades are full-size blades. The present invention connects the outlet of the combustion chamber in the combustion power generation unit with the test unit, and uses part of the high-temperature and high-pressure combustion gas generated in the combustion chamber as the mainstream combustion gas for the test. The present invention connects the outlet of the compressor in the combustion power generation unit with the air cooling unit, and uses part of the air generated in the compressor as the cooling air for the test. Finally, the turbine blade cooling effect test is completed in the test unit, which can not only make the parameters of the mainstream combustion gas and the cooling air consistent with the product process, but also can make the parameters of the mainstream combustion gas and the cooling air consistent with the product process. The working conditions are completely consistent, and the equipment investment and electricity consumption costs are greatly reduced. Compared with an independent full-pressure, full-temperature, full-size turbine blade cooling effect test bench, the present invention reduces the test fuel supply system, test combustion chamber, air electric heater, mainstream air compressor, cooling air compressor, and air electric heater, which can reduce the equipment purchase cost of the test device and the electricity consumption cost of high-pressure compression equipment and air electric heater; the present invention connects the outlet of the test unit with the combustion power generation unit, so that the mixed gas generated after the test is returned to the combustion power generation unit for reuse, and the mixed gas can enter the bottom cycle of the gas-steam combined cycle, which helps to improve the utilization efficiency of the waste heat of the mixed gas and also improves the output of the gas turbine combined cycle unit under the test conditions.

[0012] Preferably, the combustion power generation unit comprises a compressor, a combustion chamber, a power generation turbine, a gas turbine exhaust duct and a waste heat boiler which are sequentially connected along the gas flow direction.

[0013] The combustion power generation unit described in the present invention is established on the basis of a gas turbine power plant. It uses the high-temperature combustion gas generated by the original gas turbine of the power plant and the compressed air generated by the original compressor to test the cooling effect of the turbine blades. Therefore, compared with an independent full-pressure, full-temperature, full-size turbine blade cooling effect test bench, it can significantly reduce equipment investment.

[0014] Preferably, the air cooling unit comprises a cooling air intake valve, a cooling air regulating valve and a cooling air flow meter which are sequentially connected along a cooling air flow direction.

[0015] Preferably, the test unit comprises a mainstream gas inlet valve, a mainstream gas regulating valve, a compensator, a turbine blade test device, an exhaust gas desuperheater, an exhaust gas flow meter and an exhaust butterfly valve which are sequentially connected along the gas flow direction.

[0016] In the present invention, the compensator is installed before the turbine blade test device to absorb the expansion amount of the intake duct.

[0017] Preferably, the outlet of the combustion chamber of the combustion power generation unit is connected to the mainstream fuel gas inlet valve of the test unit.

[0018] Preferably, the outlet of the compressor of the combustion power generation unit is connected to the cooling air inlet valve of the air cooling unit.

[0019] Preferably, an outlet of the cooling air flow meter of the air cooling unit is connected to a turbine blade test device of the test unit.

[0020] Preferably, the outlet of the exhaust butterfly valve of the test unit is connected to the exhaust pipe of the gas turbine of the combustion power generation unit.

[0021] Preferably, the outlet pipe of the combustion chamber is connected to the inlet pipe of the turbine blade testing device, and both are double-layer pipes.

[0022] Preferably, the outlet pipe of the turbine blade testing device and the inlet pipe of the exhaust gas desuperheater are connected, and both are double-layer pipes.

[0023] In the present invention, the double-layer pipeline includes a tube side and a shell side, and adopts a high-temperature alloy double-layer cooling structure. Cooling water enters the shell side to cool the pipeline for protection. In the present invention, the pipeline after the exhaust gas cooler is made of 304 stainless steel.

[0024] Preferably, the shell of the turbine blade testing device comprises a double-layer structure.

[0025] In the present invention, the shell of the turbine blade test device is set as a double-layer structure, and a heat insulating material is installed between the double-layer shells. The heat insulating material is generally high-silica fiber felt.

[0026] Preferably, the water cooling unit comprises a water replenishment component and a cooling tower which are sequentially connected along the water flow direction.

[0027] Preferably, the water replenishment component includes a water replenishment pipeline and a water replenishment valve.

[0028] In the present invention, cooling water can be added to the cooling tower through the water supply pipeline.

[0029] In the present invention, the water cooling unit further comprises a water pump, a water outlet component and a water inlet component, the water outlet component comprises a water outlet pipe and a valve, and the water inlet component comprises a water inlet pipe and a valve.

[0030] Preferably, the outlet of the cooling tower is connected to the shell side of the outlet pipe of the combustion chamber.

[0031] Preferably, the outlet of the cooling tower is connected to the shell side of the inlet pipe of the exhaust gas desuperheater.

[0032] Preferably, the inlet of the cooling tower is connected to the shell side of the inlet pipe of the turbine blade testing device.

[0033] Preferably, the inlet of the cooling tower is connected to the shell side of the outlet pipe of the turbine blade testing device.

[0034] In the present invention, by connecting the outlet of the cooling tower with the shell side of the outlet pipe of the combustion chamber and connecting the inlet of the cooling tower with the shell side of the inlet pipe of the turbine blade test device, the cooling water can flow from the outlet of the combustion chamber to the inlet of the turbine blade test device in the shell side of the double-layer pipe, and then return to the cooling tower, thereby completing the temperature reduction protection of the pipeline.

[0035] In the present invention, by connecting the outlet of the cooling tower with the shell side of the inlet pipe of the exhaust gas cooler, and connecting the inlet of the cooling tower with the shell side of the outlet pipe of the turbine blade test device, the cooling water can flow from the inlet of the exhaust gas cooler to the outlet of the turbine blade test device in the shell side of the double-layer pipe, and then return to the cooling tower, thereby completing the temperature reduction protection of the pipeline.

[0036] Preferably, the outlet of the cooling tower is connected to the interior of the exhaust gas desuperheater.

[0037] In the present invention, the outlet of the cooling tower is connected to the inside of the exhaust gas desuperheater, so that cooling water can be directly sprayed into the exhaust gas desuperheater to cool the mixed gas.

[0038] Preferably, the turbine blade testing device includes at least one turbine blade group, for example, it can be one, two, three or four stages, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0039] Preferably, the turbine blade group includes a turbine static blade group and / or a turbine moving blade group.

[0040] In the present invention, at least one stage of turbine blade group is provided, and includes a turbine static blade group and a turbine moving blade group. The static cooling effect test of the full-size turbine static blades can be independently carried out, and the static cooling effect test of the full-size turbine moving blades can also be independently carried out. The turbine static blade group and the turbine moving blade group can also be connected in series for a joint test.

[0041] Preferably, the turbine static blade group includes at least 4 full-size turbine blades, for example, 4, 5 or 6, but not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0042] Preferably, the turbine static blade group includes at least 3 blade flow channels, for example, 3, 4 or 5, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0043] Preferably, the turbine moving blade group includes at least 7 full-size turbine blades, for example, 7, 8 or 9, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0044] Preferably, the turbine moving blade group includes at least 6 blade flow channels, for example, 6, 7 or 8, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0045] In the present invention, the two outermost blades are supporting blades, and the other blades in the middle are test blades.

[0046] Preferably, the turbine blade testing device is provided with a turbine blade internal cooling channel.

[0047] In the present invention, cooling air cools the turbine blades through the internal cooling channels of the turbine blades, and a turbine blade cooling test is performed. The obtained pressure data, temperature data, and flow data are collected and analyzed through instruments and equipment to obtain the cooling effect of the turbine blades.

[0048] In the present invention, temperature measuring points and pressure measuring points are arranged at the front end and the rear end of the turbine blade testing device.

[0049] In the present invention, the temperature of the mainstream fuel gas is measured by a temperature probe, and the metal surface temperature of the turbine blade is measured by a miniature armored thermocouple. A groove is opened on the surface of the turbine blade, and the thermocouple is embedded. The groove is then filled with plasma spraying and polished to restore the prototype surface accuracy.

[0050] In a second aspect, the present invention provides a method for testing the cooling effect of gas turbine turbine blades, wherein the method adopts the device system for testing the cooling effect of gas turbine turbine blades as described in the first aspect of the present invention.

[0051] The method comprises the following steps:

[0052] The gas produced by the combustion chamber is extracted as the mainstream gas, and the air produced by the compressor is extracted as the cooling air. The turbine blade cooling effect test is carried out to produce a mixed gas and obtain the test data of the cooling effect;

[0053] In the turbine blade cooling effect test, cooling water is used to cool the pipeline for protection;

[0054] In the turbine blade cooling effect test, cooling water is also used to cool the mixed gas, and the mixed gas after cooling is used as waste heat to generate steam.

[0055] In the present invention, by using the gas generated in the combustion chamber as the mainstream gas and the air generated by the compressor as the cooling air to test the cooling effect of the turbine blades, the parameters of the mainstream gas and the cooling air can be made completely consistent with the product working conditions, thereby reducing equipment investment and electricity consumption costs. The present invention utilizes the waste heat of the mixed gas to prepare steam, and the mixed gas can be allowed to enter the bottom cycle of the gas-steam combined cycle, which helps to improve the utilization efficiency of the waste heat of the mixed gas and improve the output of the gas turbine combined cycle unit under the test conditions.

[0056] Preferably, the mainstream gas is extracted from the combustion chamber, passes through the mainstream gas inlet valve, the mainstream gas regulating valve and the compensator in sequence, and enters the turbine blade test device to perform a turbine blade cooling effect test.

[0057] Preferably, the cooling air is extracted from the compressor, passes through a cooling air inlet valve, a cooling air regulating valve, and a cooling air flow meter in sequence, and enters a turbine blade test device to perform a turbine blade cooling effect test.

[0058] Preferably, the cooling air enters the internal cooling passage of the turbine blade from the top of the stationary blade and / or the root of the moving blade in the turbine blade testing device to perform a turbine blade cooling effect test.

[0059] Preferably, the mixed gas enters the waste heat boiler through the exhaust gas desuperheater, the exhaust gas flowmeter, the exhaust butterfly valve and the gas turbine exhaust pipe to utilize the waste heat to generate steam.

[0060] Preferably, the flow rate of the mainstream gas is controlled by a mainstream gas inlet valve and a mainstream gas regulating valve.

[0061] Preferably, the pressure of the mainstream gas is controlled by an exhaust butterfly valve.

[0062] Preferably, the flow rate of the cooling air is controlled by a cooling air intake valve and a cooling air regulating valve.

[0063] Preferably, in each stage of turbine blade group, the flow rate of the mainstream fuel gas accounts for 5.71-5.83% of the total flow rate of the fuel gas at the combustion chamber outlet, for example, it can be 5.71%, 5.72%, 5.73%, 5.74%, 5.75%, 5.76%, 5.77%, 5.78%, 5.79%, 5.80%, 5.81%, 5.82% or 5.83%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0064] Preferably, in each stage of turbine blade group, the flow rate of the cooling air accounts for 0.43-0.58% of the total flow rate of the compressor outlet air, for example, it can be 0.43%, 0.44%, 0.46%, 0.48%, 0.50%, 0.52%, 0.54%, 0.56% or 0.58%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0065] Preferably, the test data include the metal surface temperature of the turbine blades, the temperature of the mainstream combustion gas before the turbine blade test device, the pressure of the mainstream combustion gas before the turbine blade test device, the outlet static pressure of the turbine blade test device, the flow rate of the mixed gas after the turbine blade test device, the temperature of the cooling air before the turbine blade test device, the pressure of the cooling air before the turbine blade test device and the flow rate of the cooling air before the turbine blade test device.

[0066] Preferably, the metal surface temperature of the turbine blades includes the metal wall temperature of the turbine blade body, the metal surface temperature of the upper end wall of the turbine stator blade, the metal surface temperature of the lower end wall of the turbine stator blade and the metal surface temperature of the platform of the turbine moving blade.

[0067] As a preferred technical solution of the second aspect of the present invention, the method comprises the following steps:

[0068] The mainstream gas is extracted from the combustion chamber and enters the turbine blade test device through the mainstream gas intake valve, the mainstream gas regulating valve and the compensator in sequence; the cooling air is extracted from the compressor and enters the turbine blade test device through the cooling air intake valve, the cooling air regulating valve and the cooling air flow meter in sequence; the cooling air enters the internal cooling channel of the turbine blade from the top of the stationary blade and / or the root of the moving blade to perform a turbine blade cooling effect test, generate a mixed gas and obtain test data of the cooling effect;

[0069] In the turbine blade cooling effect test, cooling water enters from the outlet pipe of the combustion chamber, flows along the shell side of the double-layer pipe, flows out from the inlet pipe of the turbine blade test device, and returns to the cooling tower; cooling water also enters from the inlet pipe of the exhaust gas desuperheater, flows along the shell side of the double-layer pipe, flows out from the outlet pipe of the turbine blade test device, and returns to the cooling tower, completing the temperature reduction protection of the pipeline;

[0070] In the turbine blade cooling effect test, cooling water is also used to enter the exhaust gas desuperheater to cool the mixed gas to a temperature of less than 700°C. The cooled mixed gas enters the waste heat boiler through the exhaust flow meter, the exhaust butterfly valve and the gas turbine exhaust pipe to utilize the waste heat and generate steam.

[0071] The flow rate of the mainstream gas is controlled by the mainstream gas inlet valve and the mainstream gas regulating valve; the pressure of the mainstream gas is controlled by the exhaust butterfly valve; the flow rate of the cooling air is controlled by the cooling air inlet valve and the cooling air regulating valve; in each stage of the turbine blade group, the flow rate of the mainstream gas accounts for 5.71-5.83% of the total flow rate of the gas at the combustion chamber outlet; in each stage of the turbine blade group, the flow rate of the cooling air accounts for 0.43-0.58% of the total flow rate of the compressor outlet air;

[0072] The test data include the metal surface temperature of the turbine blades, the temperature of the mainstream combustion gas before the turbine blade test device, the pressure of the mainstream combustion gas before the turbine blade test device, the outlet static pressure of the turbine blade test device, the flow rate of the mixed gas after the turbine blade test device, the temperature of the cooling air before the turbine blade test device, the pressure of the cooling air before the turbine blade test device and the flow rate of the cooling air before the turbine blade test device; the metal surface temperature of the turbine blade includes the metal wall temperature of the blade body of the turbine blade, the metal surface temperature of the upper end wall of the turbine static vane, the metal surface temperature of the lower end wall of the turbine static vane and the metal surface temperature of the platform of the turbine moving blade.

[0073] Compared with the prior art, the present invention has the following beneficial effects:

[0074] (1) The device system structure for testing the cooling effect of gas turbine blades provided by the present invention is simple. Compared with an independent full-pressure, full-temperature, full-size turbine blade cooling effect test bench, the present invention reduces the test fuel supply system, test combustion chamber, air electric heater, mainstream air compressor, cooling air compressor and air electric heater, thereby reducing the equipment purchase cost of the test device and the electricity consumption cost of the high-pressure compression equipment and the air electric heater.

[0075] (2) The method for testing the cooling effect of gas turbine blades provided by the present invention uses part of the fuel gas produced in the combustion chamber as the mainstream fuel gas and part of the air produced by the compressor as the cooling air. This can make the parameters of the turbine blade cooling effect test completely consistent with the actual working conditions and can be used to conduct full-temperature, full-pressure and full-scale tests on turbine static and moving blades.

[0076] (3) The method provided by the present invention for testing the cooling effect of gas turbine blades injects the mixed gas after the test back into the combustion power generation unit, so that the mixed gas enters the bottom cycle of the gas-steam combined cycle, which helps to improve the utilization efficiency of the waste heat of the mixed gas and improve the output of the gas turbine combined cycle unit under the test conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 It is a schematic diagram of the structure of the device system for testing the cooling effect of gas turbine blades described in Example 1 of the present invention.

[0078] Figure 2 It is a schematic diagram of the first-stage moving blade group in Example 1 of the present invention.

[0079] Among them, 1-combustion power generation unit; 2-air cooling unit; 3-test unit; 4-water cooling unit; 5-combustion chamber; 6-compressor; 7-power turbine; 8-gas turbine exhaust duct; 9-cooling air intake valve; 10-cooling air regulating valve; 11-cooling air flow meter; 12-mainstream gas intake valve; 13-mainstream gas regulating valve; 14-compensator; 15-turbine blade test device; 16-exhaust desuperheater; 17-exhaust flow meter; 18-exhaust butterfly valve; 19-water supply pipe and valve; 20-cooling tower; 21-water pump; 22-water outlet pipe and valve; 23-water inlet pipe and valve; 24-first stage moving blade group. DETAILED DESCRIPTION

[0080] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0081] Example 1

[0082] This embodiment provides a device system for testing the cooling effect of gas turbine blades. Figure 1 As shown, the device system includes a combustion power generation unit 1, an air cooling unit 2, a test unit 3 and a water cooling unit 4; the outlet of the combustion chamber 5 in the combustion power generation unit 1 is connected to the test unit 3; the outlet of the compressor 6 in the combustion power generation unit 1 is connected to the air cooling unit 2; the outlet of the air cooling unit 2 is connected to the test unit 3; the outlet of the water cooling unit 4 is respectively connected to the test unit 3 and the combustion power generation unit 1; the outlet of the test unit 3 is connected to the combustion power generation unit 1.

[0083] The combustion power generation unit 1 includes a compressor 6, a combustion chamber 5, a power generation turbine 7, a gas turbine exhaust pipe 8 and a waste heat boiler connected in sequence along the gas flow direction; the air cooling unit 2 includes a cooling air intake valve 9, a cooling air regulating valve 10 and a cooling air flow meter 11 connected in sequence along the cooling air flow direction; the test unit 3 includes a mainstream gas intake valve 12, a mainstream gas regulating valve 13, a compensator 14, a turbine blade test device 15, an exhaust gas desuperheater 16, an exhaust gas flow meter 17 and an exhaust butterfly valve 18 connected in sequence along the gas flow direction;

[0084] The outlet of the combustion chamber 5 of the combustion power generation unit 1 is connected to the mainstream fuel gas intake valve 12 of the test unit 3; the outlet of the compressor 6 of the combustion power generation unit 1 is connected to the cooling air intake valve 9 of the air cooling unit 2; the outlet of the cooling air flow meter 11 of the air cooling unit 2 is connected to the turbine blade test device 15 of the test unit 3; the outlet of the exhaust butterfly valve 18 of the test unit 3 is connected to the gas turbine exhaust pipe 8 of the combustion power generation unit 1; the outlet pipe of the combustion chamber 5 is connected to the inlet pipe of the turbine blade test device 15, and both are double-layer pipes; the outlet pipe of the turbine blade test device 15 is connected to the inlet pipe of the exhaust gas desuperheater 16, and both are double-layer pipes; the shell of the turbine blade test device 15 is a double-layer structure;

[0085] The water cooling unit 4 includes a water supply component and a cooling tower 20 which are sequentially connected along the water flow direction; the water supply component includes a water supply pipe and a valve 19; the water cooling unit 4 also includes a water pump 21, a water outlet component and a water inlet component; the water outlet component includes a water outlet pipe and a valve 22; the water inlet component includes a water inlet pipe and a valve 23; the outlet of the cooling tower 20 is connected to the shell side of the outlet pipe of the combustion chamber 5; the outlet of the cooling tower 20 is connected to the shell side of the inlet pipe of the exhaust gas desuperheater 16; the inlet of the cooling tower 20 is connected to the shell side of the inlet pipe of the turbine blade test device 15; the inlet of the cooling tower 20 is connected to the shell side of the outlet pipe of the turbine blade test device 15; the outlet of the cooling tower 20 is connected to the inside of the exhaust gas desuperheater 16;

[0086] The turbine blade test device 15 includes a first-stage turbine blade group; the turbine blade group includes a turbine stationary blade group (referred to as the first-stage stationary blade group) and a turbine moving blade group (referred to as the first-stage moving blade group 24); the first-stage stationary blade group includes 4 full-size turbine blades and 3 blade flow passages; the first-stage moving blade group 24 is as follows Figure 2 As shown, it includes 7 full-size turbine blades and 6 blade flow passages.

[0087] This embodiment also provides a method for testing the cooling effect of gas turbine blades using the above-mentioned device system, the method comprising the following steps:

[0088] The mainstream gas is extracted from the combustion chamber 5, and enters the turbine blade test device 15 through the mainstream gas intake valve 12, the mainstream gas regulating valve 13 and the compensator 14 in sequence; the cooling air is extracted from the compressor 6, and enters the turbine blade test device 15 through the cooling air intake valve 9, the cooling air regulating valve 10 and the cooling air flow meter 11 in sequence; the cooling air enters the internal cooling channel of the turbine blade from the top of the stationary blade and the root of the moving blade, and the turbine blade cooling effect test is carried out to generate a mixed gas and obtain the test data of the cooling effect;

[0089] In the turbine blade cooling effect test, cooling water enters from the outlet pipe of the combustion chamber 5, flows along the shell side of the double-layer pipe, flows out from the inlet pipe of the turbine blade test device 15, and returns to the cooling tower 20; cooling water also enters from the inlet pipe of the exhaust gas desuperheater 16, flows along the shell side of the double-layer pipe, flows out from the outlet pipe of the turbine blade test device 15, and returns to the cooling tower 20, completing the temperature reduction protection of the pipeline;

[0090] In the turbine blade cooling effect test, cooling water is also used to enter the exhaust gas desuperheater 16 to cool the mixed gas to a temperature of 650° C. The cooled mixed gas enters the waste heat boiler through the exhaust flow meter 17, the exhaust butterfly valve 18 and the gas turbine exhaust pipe to utilize the waste heat to generate steam.

[0091] The flow rate of the mainstream gas is controlled by the mainstream gas inlet valve and the mainstream gas regulating valve; the pressure of the mainstream gas is controlled by the exhaust butterfly valve 18; the flow rate of the cooling air is controlled by the cooling air inlet valve and the cooling air regulating valve; in the first-stage stationary blade group, the flow rate of the mainstream gas accounts for 5.71% of the total flow rate of the gas at the outlet of the combustion chamber 5, and the flow rate of the cooling air accounts for 0.58% of the total flow rate of the air at the outlet of the compressor 6; in the first-stage moving blade group 24, the flow rate of the mainstream gas accounts for 5.83% of the total flow rate of the gas at the outlet of the combustion chamber 5, and the flow rate of the cooling air accounts for 0.43% of the total flow rate of the air at the outlet of the compressor 6;

[0092] The test data include the metal surface temperature of the turbine blades, the temperature of the mainstream combustion gas before the turbine blade test device 15, the pressure of the mainstream combustion gas before the turbine blade test device 15, the outlet static pressure of the turbine blade test device 15, the flow rate of the mixed gas after the turbine blade test device 15, the temperature of the cooling air before the turbine blade test device 15, the pressure of the cooling air before the turbine blade test device 15 and the flow rate of the cooling air before the turbine blade test device 15; the metal surface temperature of the turbine blade includes the metal wall temperature of the blade body of the turbine blade, the metal surface temperature of the upper end wall of the turbine static vane, the metal surface temperature of the lower end wall of the turbine static vane and the metal surface temperature of the platform of the turbine moving blade.

[0093] For a certain model of 400MW G / H class gas turbine, the compressor inlet air flow is 855kg / s, the combustion chamber fuel flow is 20kg / s, and the above-mentioned device system and method are used. The calculation results of the mainstream gas flow and the cold zone gas flow are shown in Table 1.

[0094] Table 1

[0095]

[0096]

[0097] As can be seen from Table 1, in the device system and method provided in this embodiment, in the first-stage stationary blade group and the first-stage moving blade group, the flow rate of the mainstream fuel gas accounts for less than 5.83% of the total flow rate of the fuel gas at the combustion chamber outlet, and the flow rate of the cooling gas accounts for less than 0.58% of the total flow rate of the air at the compressor outlet, which will not affect the safe operation of the gas turbine of the power plant.

[0098] Compared with an independent full-pressure, full-temperature, full-size turbine blade cooling effect test bench, this embodiment can reduce the test fuel supply system, combustion chamber, mainstream air compressor, cooling air compressor, and air electric heater; the reduced fuel supply system includes a regulating valve station, a heating device, a shut-off valve group, a regulating valve group, a measuring device, and a nitrogen purge device, etc.

[0099] Compared with an independent full-pressure, full-temperature, full-size turbine blade cooling effect test bench, this embodiment can save 50-90 million yuan in equipment purchase costs. The power of these equipments is 25,000-30,000 kW. Five working conditions are performed according to one turbine blade cooling effect test. Each working condition is calculated as 1 hour, and the test electricity consumption is 125,000 kW·h-150,000 kW·h. If industrial electricity is calculated at a power consumption cost of 0.9 yuan / kW·h, the device system and method provided by this embodiment can save 112,500-135,000 yuan.

[0100] Compared with an independent full-pressure, full-temperature, full-size turbine blade cooling effect test bench, the device system and method provided in this embodiment utilizes mixed gas to enter the waste heat boiler, which increases the turbine output by 6%. Calculated based on the turbine output of 200MW, the power generation capacity can be increased by 12MW during the test.

[0101] In summary, the device system for testing the cooling effect of gas turbine turbine blades provided by the present invention can save equipment costs and electricity costs, and the method for testing the cooling effect of gas turbine turbine blades provided by the present invention can improve the capacity utilization efficiency and improve the output of the gas turbine combined cycle unit under test conditions.

[0102] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A device system for testing the cooling effect of gas turbine blades, characterized in that: The device system includes a combustion power generation unit, an air cooling unit, a test unit and a water cooling unit; The combustion power generation unit comprises a compressor, a combustion chamber, a power generation turbine, a gas turbine exhaust pipe and a waste heat boiler which are sequentially connected along the gas flow direction; The air cooling unit comprises a cooling air intake valve, a cooling air regulating valve and a cooling air flow meter which are sequentially connected along the cooling air flow direction; The test unit includes a mainstream gas inlet valve, a mainstream gas regulating valve, a compensator, a turbine blade test device, an exhaust gas desuperheater, an exhaust gas flow meter and an exhaust butterfly valve which are sequentially connected along the gas flow direction; The turbine blade test device includes at least one stage of turbine blade assembly; The outlet of the combustion chamber of the combustion power generation unit is connected to the mainstream fuel gas inlet valve of the test unit; The outlet of the compressor of the combustion power generation unit is connected to the cooling air inlet valve of the air cooling unit; The outlet of the cooling air flow meter of the air cooling unit is connected to the turbine blade test device of the test unit; The outlet of the exhaust butterfly valve of the test unit is connected to the exhaust pipe of the gas turbine of the combustion power generation unit; The outlet of the water cooling unit is connected to the test unit and the combustion power generation unit respectively; The outlet pipe of the combustion chamber is connected to the inlet pipe of the turbine blade test device, and both are double-layer pipes; the outlet pipe of the turbine blade test device is connected to the inlet pipe of the exhaust gas cooler, and both are double-layer pipes; the shell of the turbine blade test device is a double-layer structure; The water cooling unit includes a water supply component and a cooling tower connected in sequence along the water flow direction; the water supply component includes a water supply pipeline and a water supply valve; the outlet of the cooling tower is connected to the shell side of the outlet pipe of the combustion chamber; the outlet of the cooling tower is connected to the shell side of the inlet pipe of the exhaust gas desuperheater; the inlet of the cooling tower is connected to the shell side of the inlet pipe of the turbine blade test device; the inlet of the cooling tower is connected to the shell side of the outlet pipe of the turbine blade test device; the outlet of the cooling tower is connected to the inside of the exhaust gas desuperheater; The turbine blade group includes a turbine static blade group and / or a turbine moving blade group; the turbine static blade group includes at least 4 full-size turbine blades; the turbine static blade group includes at least 3 blade flow channels; the turbine moving blade group includes at least 7 full-size turbine blades; the turbine moving blade group includes at least 6 blade flow channels.

2. A method for testing the cooling effect of gas turbine blades, characterized in that: The method adopts the device system for testing the cooling effect of gas turbine blades as claimed in claim 1; The method comprises the following steps: The gas produced by the combustion chamber is extracted as the mainstream gas, and the air produced by the compressor is extracted as the cooling air. The turbine blade cooling effect test is carried out to produce a mixed gas and obtain the test data of the cooling effect; In the turbine blade cooling effect test, cooling water is used to cool the pipeline for protection; In the turbine blade cooling effect test, cooling water is also used to cool the mixed gas, and the mixed gas after cooling is used as waste heat to generate steam.

3. The method according to claim 2, characterized in that The mainstream fuel gas is extracted from the combustion chamber, passes through the mainstream fuel gas inlet valve, the mainstream fuel gas regulating valve and the compensator in sequence, and enters the turbine blade test device to perform a turbine blade cooling effect test.

4. The method according to claim 2, characterized in that: The cooling air is extracted from the compressor and passes through the cooling air inlet valve, the cooling air regulating valve and the cooling air flow meter in sequence and enters the turbine blade test device to perform a turbine blade cooling effect test.

5. The method according to claim 4, characterized in that The cooling air enters the internal cooling passage of the turbine blade from the top of the stationary blade and / or the root of the moving blade in the turbine blade testing device to carry out a turbine blade cooling effect test.

6. The method according to claim 2, characterized in that The mixed gas enters the waste heat boiler through the exhaust gas desuperheater, the exhaust gas flow meter, the exhaust butterfly valve and the gas turbine exhaust pipe to utilize the waste heat to generate steam.

7. The method according to claim 3, characterized in that The flow rate of the mainstream gas is controlled by a mainstream gas inlet valve and a mainstream gas regulating valve.

8. The method according to claim 6, characterized in that The pressure of the mainstream fuel gas is controlled by an exhaust butterfly valve.

9. The method according to claim 4, characterized in that The flow rate of the cooling air is controlled by a cooling air intake valve and a cooling air regulating valve.

10. The method according to claim 2, characterized in that In each stage of turbine blade group, the flow rate of the mainstream fuel gas accounts for 5.71-5.83% of the total flow rate of fuel gas at the combustion chamber outlet.

11. The method according to claim 2, characterized in that In each stage of turbine blade group, the flow rate of the cooling air accounts for 0.43-0.58% of the total flow rate of the compressor outlet air.

12. The method according to claim 2, characterized in that: The test data include the metal surface temperature of the turbine blades, the temperature of the mainstream combustion gas before the turbine blade test device, the pressure of the mainstream combustion gas before the turbine blade test device, the outlet static pressure of the turbine blade test device, the flow rate of the mixed gas after the turbine blade test device, the temperature of the cooling air before the turbine blade test device, the pressure of the cooling air before the turbine blade test device and the flow rate of the cooling air before the turbine blade test device.

13. The method according to claim 12, characterized in that The metal surface temperature of the turbine blades includes the metal wall temperature of the turbine blade body, the metal surface temperature of the upper end wall of the turbine stator blade, the metal surface temperature of the lower end wall of the turbine stator blade and the metal surface temperature of the platform of the turbine moving blade.

14. The method according to claim 2, characterized in that The method comprises the following steps: The mainstream gas is extracted from the combustion chamber and enters the turbine blade test device through the mainstream gas intake valve, the mainstream gas regulating valve and the compensator in sequence; the cooling air is extracted from the compressor and enters the turbine blade test device through the cooling air intake valve, the cooling air regulating valve and the cooling air flow meter in sequence; the cooling air enters the internal cooling channel of the turbine blade from the top of the stationary blade and / or the root of the moving blade to perform a turbine blade cooling effect test, generate a mixed gas and obtain test data of the cooling effect; In the turbine blade cooling effect test, cooling water enters from the outlet pipe of the combustion chamber, flows along the shell side of the double-layer pipe, flows out from the inlet pipe of the turbine blade test device, and returns to the cooling tower; cooling water also enters from the inlet pipe of the exhaust gas desuperheater, flows along the shell side of the double-layer pipe, flows out from the outlet pipe of the turbine blade test device, and returns to the cooling tower, completing the temperature reduction protection of the pipeline; In the turbine blade cooling effect test, cooling water is also used to enter the exhaust gas desuperheater to cool the mixed gas to a temperature of less than 700°C. The cooled mixed gas enters the waste heat boiler through the exhaust flow meter, the exhaust butterfly valve and the gas turbine exhaust pipe to utilize the waste heat and generate steam. The flow rate of the mainstream gas is controlled by the mainstream gas inlet valve and the mainstream gas regulating valve; the pressure of the mainstream gas is controlled by the exhaust butterfly valve; the flow rate of the cooling air is controlled by the cooling air inlet valve and the cooling air regulating valve; in each stage of the turbine blade group, the flow rate of the mainstream gas accounts for 5.71-5.83% of the total flow rate of the gas at the combustion chamber outlet; in each stage of the turbine blade group, the flow rate of the cooling air accounts for 0.43-0.58% of the total flow rate of the compressor outlet air; The test data include the metal surface temperature of the turbine blades, the temperature of the mainstream combustion gas before the turbine blade test device, the pressure of the mainstream combustion gas before the turbine blade test device, the outlet static pressure of the turbine blade test device, the flow rate of the mixed gas after the turbine blade test device, the temperature of the cooling air before the turbine blade test device, the pressure of the cooling air before the turbine blade test device and the flow rate of the cooling air before the turbine blade test device; the metal surface temperature of the turbine blade includes the metal wall temperature of the blade body of the turbine blade, the metal surface temperature of the upper end wall of the turbine static vane, the metal surface temperature of the lower end wall of the turbine static vane and the metal surface temperature of the platform of the turbine moving blade.

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