Retrofitting Method for Compressor of Gas Turbine in High-Temperature Environment

Abstract

The present invention provides a modification method for a compressor of a gas turbine in a high-temperature environment, comprising the following steps: Step 1), determining structural constraints, a target value of the first compressor flow rate increase rate, and a target value of the second compressor flow rate increase rate; Step 2), sensitivity analysis of the blade installation angle; Step 3), evaluating whether the number of improved blades meets the project requirements; Step 4), adjusting the change amount of the installation angle of the improved blades; Step 5), whether it meets other performance requirements of the compressor and the structural constraints of the compressor modification design; Step 6), airfoil optimization; Step 7), adjusting the opening degree of the adjustable guide vane; Step 8), whether the target value of the second compressor flow rate increase rate is achieved; Step 9), whether the design goal is achieved. This modification method first improves and optimizes the blades, adjusts the load distribution of each stage of the compressor, reduces the load of the inlet stage under ISO conditions, and provides more space for increasing the opening degree of the adjustable guide vane in a high-temperature environment.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbines, and particularly to a modification method for a compressor of a gas turbine in a high-temperature environment. Background Art

[0002] The performance guarantee condition of a gas turbine is generally set as the ISO standard condition, with an ambient temperature of 15°C, an absolute atmospheric pressure of 101.325 kPa, and an atmospheric relative humidity of 60%, which is also the design condition of the gas turbine. When the other conditions remain unchanged, the flow rate of the gas turbine compressor will decrease with the increase of the ambient temperature, resulting in a decrease in the output of the entire gas turbine. This is determined by the general characteristics of the compressor. However, if the output attenuation of the gas turbine in a high-temperature environment is too fast, it will greatly affect its product competitiveness in gas turbine project bidding in southern regions with higher summer temperatures and low-latitude countries in Asia, Africa, and Latin America. A high-temperature environment refers to an ambient temperature greater than 28°C.

[0003] In order to improve the product competitiveness in regions with a relatively high average ambient temperature, it is not only necessary to ensure the performance indicators such as the flow rate, pressure ratio, efficiency, and margin of the compressor under ISO conditions, but also to increase the flow rate of the gas turbine compressor in a high-temperature environment. To achieve this goal, there are two main ways: First, in hot weather, increase the opening of the adjustable guide vane within a safe range, that is, over-open based on the original design opening of 100%, so as to increase the compressor flow rate. However, this method will significantly increase the load of the first-stage moving blade, resulting in a decrease in the compressor efficiency and possible rotational stall, and can only increase the compressor flow rate by a small margin. Its advantage is that it will not change the design performance of the compressor under ISO conditions. Second, by optimizing the blade profiles of some stages of the compressor and adjusting the load distribution of each stage, so that it can maintain a high flow capacity of the compressor within a wide temperature range, slow down the decline trend of the compressor flow rate when the temperature rises, and at the same time keep the compressor efficiency at a relatively high level. However, this method has a large design difficulty and needs to take into account the compressor performance under ISO conditions and hot weather conditions. How to combine the above two ways to design a modification method for improving the flow rate of the gas turbine compressor in hot weather, so that the compressor has considerable performance at normal temperature and in hot weather, is a problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of the above-mentioned disadvantages of the prior art, the technical problem to be solved by the present invention is to provide a modification method for a gas turbine compressor that can increase the flow rate of the gas turbine compressor in hot weather and enable the compressor to have considerable performance at normal temperature and in hot weather.

[0005] To solve the above technical problem, the present invention provides a modification method for a compressor of a gas turbine in a high-temperature environment, including the following steps:

[0006] Step 1): Determine the structural constraints for the compressor retrofit design, the target value of the first compressor flow rate increase rate after only improving the blade profile, and the target value of the second compressor flow rate increase rate after superimposing the improvement of the adjustable guide vane opening on the basis of improving the blade profile; the blades include rotor blades and stator blades;

[0007] Step 2): According to the sensitivity analysis of the installation angle of the blades, obtain the flow rate increase rate after the installation angle of each row of blades is changed, and sort the flow rate increase rates after the installation angle of each row of blades is changed in descending order of the absolute value of the numerical value; among each row of blades, the blades with the flow rate increase rate after the installation angle is changed greater than the target value of the first compressor flow rate increase rate and whose numerical absolute value ranking is before the preset ranking are used as the initial improved blades;

[0008] Step 3): Evaluate whether the number of improved blades meets the project requirements. When the number of improved blades meets the preset project requirements, proceed to Step 4); when the number of improved blades does not meet the project requirements, reduce the number of improved blades by several rows so that the number of improved blades meets the project requirements, and proceed to Step 4); when first evaluating whether the number of improved blades meets the project requirements, the number of improved blades is the number of initial improved blades in Step 2);

[0009] Step 4): Adjust the installation angle change amount of the improved blades determined in Step 3) to determine whether the final blade installation angle change amount can be determined; if the final blade installation angle change amount can be determined, proceed to Step 5); if the final blade installation angle change amount cannot be determined, increase the number of improved blades and then return to Step 3);

[0010] Step 5): If the final blade installation angle change amount determined in Step 4) can meet the other performance requirements of the compressor and the structural constraints of the compressor retrofit design, proceed to Step 7); if the final blade installation angle change amount determined in Step 4) cannot meet the other performance requirements of the compressor or the structural constraints of the compressor retrofit design, proceed to Step 6);

[0011] Step 6): Optimize the blade profile of the improved blades according to the preset number of times; after each blade profile optimization of the improved blades, return to Step 5); if it is not possible to proceed to Step 8) after the blade profile of the improved blades has been optimized according to the preset number of times, increase the number of improved blades and then return to Step 3);

[0012] Step 7): Adjust the opening of the adjustable guide vane; combine the adjusted adjustable guide vane with the determined final blade installation angle change amount, and calculate the compressor flow rate increase rate after the improved guide vane through three-dimensional CFD software;

[0013] Step 8): When the compressor flow rate improvement rate after improving the guide vane reaches the second compressor flow rate improvement rate target value, determine the opening degree of the adjustable guide vane after adjustment and proceed to Step 9); when the compressor flow rate improvement rate after improving the guide vane does not reach the second compressor flow rate improvement rate target value, return to Step 7); when after adjusting the opening degree of the adjustable guide vane through Step 7 for a preset number of times, Step 9 cannot be performed, then increase the number of improved blades and return to Step 3);

[0014] Step 9): When the opening degree of the adjustable guide vane after adjustment determined in Step 8, combined with the determined final blade installation angle change amount, meets the other performance requirements of the compressor and the structural constraints of the compressor retrofit design, the design goal is achieved; when the opening degree of the adjustable guide vane after adjustment determined in Step 8, combined with the determined final blade installation angle change amount, does not meet the other performance requirements of the compressor or the structural constraints of the compressor retrofit design, return to Step 7); when after adjusting the opening degree of the adjustable guide vane through Step 7 for a preset number of times, the design goal cannot be achieved, then increase the number of improved blades and return to Step 3).

[0015] Preferably, in Step 4), adjust the installation angle change amount of the improved blade determined in Step 3), and calculate the compressor flow rate improvement rate after the corresponding blade installation angle change through a three-dimensional CFD software; when the compressor flow rate improvement rate after the blade installation angle change is greater than or equal to the first compressor flow rate improvement rate target value, the installation angle change amount of the improved blade can be determined as the final blade installation angle change amount, and then proceed to Step 5); when the compressor flow rate improvement rate after the blade installation angle change is less than the first compressor flow rate improvement rate target value, increase the number of improved blades and return to Step 3).

[0016] Preferably, the following step is added between Step 3) and Step 4):

[0017] Calculate the compressor flow rate improvement rate after the corresponding blade installation angle change by using a one-dimensional average streamline calculation method for the installation angle change amount of the improved blade determined in Step 3), to judge whether the preliminary blade installation angle change amount can be determined. If the compressor flow rate improvement rate after the corresponding blade installation angle change calculated by using the one-dimensional average streamline calculation method is greater than or equal to the first compressor flow rate improvement rate target value, the preliminary blade installation angle change amount can be determined, and then proceed to Step 4); if the compressor flow rate improvement rate after the corresponding blade installation angle change calculated by using the one-dimensional average streamline calculation method is less than the first compressor flow rate improvement rate target value, the preliminary blade installation angle change amount cannot be determined, and the number of improved blades needs to be increased and then return to Step 3).

[0018] Preferably, the sensitivity analysis of the installation angle of the blade in Step 2) includes the following steps:

[0019] 2a), Calculate the flow rate m under the ISO condition of the prototype compressor using the one-dimensional average streamline calculation method ISO_00 and the flow rate m under the HTC condition of the prototype compressor HTC_00 ;

[0020] 2b), Set the installation angle of the first-stage rotor blade to be reduced by α degrees, and the remaining rotor blades remain the same as those of the prototype compressor. Then, use the one-dimensional average streamline calculation method to calculate the flow rate m under the ISO condition of the compressor after the installation angle of the first-stage rotor blade is reduced by α degrees ISO_1-α and the flow rate m under the HTC condition of the compressor after the installation angle of the first-stage rotor blade is reduced by α degrees HTC_1-α ;

[0021] 2c), Referring to the operation method of the first-stage rotor blade in 2b), gradually reduce the installation angle of the rotor blade by α degrees row by row, and the remaining rotor blades remain the same as those of the prototype compressor. Then, use the one-dimensional average streamline calculation method to calculate the flow rate m of the compressor under the ISO condition after the installation angle of the nth-stage rotor blade is reduced by α degrees ISO_n-α and the flow rate m of the compressor under the HTC condition HTC_n-α ;

[0022] According to the following formula, calculate the flow rate increase rate ξ after the installation angle of each row of rotor blades is reduced stg-α_n :

[0023]

[0024] 2d), Gradually increase the installation angle of each row of rotor blades by α degrees. According to the same operation in 3c), use the one-dimensional average streamline calculation method to calculate the flow rate m of the compressor under the ISO condition after the installation angle of the nth-stage rotor blade is increased by α degrees ISO_n+α and the flow rate m of the compressor under the HTC condition HTC_n+α ; Calculate the flow rate increase rate ξ after the installation angle of each row of rotor blades is increased respectively stg+α_n , and the formula is as follows:

[0025]

[0026] 3e), Gradually reduce the installation angle of each row of stator blades by α degrees. According to the same operation in 2b) and 2c), calculate the flow rate increase rate after the installation angle of each row of stator blades is reduced respectively; Gradually increase the installation angle of each row of stator blades by α degrees. According to the same operation in 2d), calculate the flow rate increase rate after the installation angle of each row of stator blades is increased respectively

[0027] Preferably, in step 2), the flow rate improvement rates after changing the installation angles of each row of blades are sorted according to the absolute values of the numerical values, that is, the absolute values of the numerical values of the flow rate improvement rates after reducing the installation angles of each row of moving blades, the absolute values of the numerical values of the flow rate improvement rates after increasing the installation angles of each row of moving blades, the absolute values of the numerical values of the flow rate improvement rates after reducing the installation angles of each row of stationary blades, and the flow rate improvement rates after increasing the installation angles of each row of stationary blades are sorted according to the absolute values of the numerical values.

[0028] Preferably, the project requirements in step 3) include the retrofit cost and the project cycle.

[0029] Preferably, the other performance requirements of the compressor include the pressure ratio, efficiency, and surge margin of the compressor.

[0030] Preferably, when the structural constraint in the retrofit design of the compressor requires that the compressor disk is not changed, then in the range of 15% - 100% of the blade height of the improved blade, it rotates by the corresponding angle according to the final change amount of the blade installation angle. Starting from 15% of the blade height of the improved blade, the installation angle linearly transitions to the 0% blade height section, and the installation angle of the 0% blade height section of the improved blade is the same as the original blade profile.

[0031] Preferably, the following steps are added between step 1) and step 2): Use three-dimensional CFD software to calculate the flow rate of the prototype compressor under ISO conditions and HTC conditions; Use three-dimensional CFD software to calculate the other performance requirements of the prototype compressor under ISO conditions and HTC conditions.

[0032] As described above, the retrofit method for the compressor of a gas turbine in a high-temperature environment of the present invention has the following beneficial effects:

[0033] The retrofit method for the compressor of a gas turbine in a high-temperature environment of the present invention combines two approaches of improving the blade and adjusting the adjustable guide vane according to the law of the characteristics of each stage of the multistage compressor changing with temperature. While ensuring the performance under ISO conditions, it effectively improves the performance of the compressor in high-temperature weather; By using the retrofit method of the present invention, through the sensitivity analysis of the installation angle of the blade, the flow rate improvement rate after changing the installation angle of each row of blades is obtained, which can quickly determine the range and direction of the improved blade, select the row of blades that is most effective in improving the flow rate, and improve the optimization efficiency; At the same time, compared with the method of simply increasing the opening degree of the adjustable guide vane to increase the flow rate of the compressor in a high-temperature environment, the retrofit method of the present invention first improves and optimizes the blade, adjusts the load distribution of each stage of the compressor, reduces the load of the inlet stage under ISO conditions, provides more space for increasing the opening degree of the adjustable guide vane in a high-temperature environment, and can also ensure the project requirements and other performance requirements of the compressor. Brief Description of the Drawings

[0034] Figure 1The flowchart of the modification method of the gas turbine compressor in a high-temperature environment according to this embodiment is shown. Detailed implementation manners

[0035] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0036] Please refer to the attached drawings. It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they do not have technical essential meanings. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle", and "one" cited in this specification are only for the convenience of clear narration, and are not used to limit the scope for the implementation of the present invention. The change or adjustment of their relative relationships, without substantial change of the technical content, should also be regarded as the scope for the implementation of the present invention.

[0037] As Figure 1 shown, the modification method of the gas turbine compressor in a high-temperature environment according to this embodiment includes the following steps:

[0038] Step 1): Determine the structural constraints for the compressor modification design, the target value of the first compressor flow rate increase rate after only improving the blade profile, and the target value of the second compressor flow rate increase rate by superimposing the improvement of the adjustable guide vane opening on the basis of improving the blade profile; the blades include moving blades and stationary blades;

[0039] Step 2): According to the sensitivity analysis of the installation angle of the blades, obtain the flow rate increase rate after the installation angle of each row of blades is changed, and sort the flow rate increase rates after the installation angle of each row of blades according to the absolute value of the numerical value; among each row of blades, the blades with the flow rate increase rate after the installation angle change greater than the target value of the first compressor flow rate increase rate and the absolute value of the numerical value ranking before the preset ranking are used as the initial improved blades;

[0040] Step 3): Evaluate whether the number of improved blades meets the project requirements. When the number of improved blades meets the preset project requirements, proceed to Step 4); when the number of improved blades does not meet the project requirements, reduce the number of improved blades by several rows so that the number of improved blades meets the project requirements, and proceed to Step 4); when initially evaluating whether the number of improved blades meets the project requirements, the number of improved blades is the number of the initial improved blades in Step 2);

[0041] Step 4): Adjust the change amount of the installation angle of the improved blade determined in Step 3) to determine whether the final change amount of the blade installation angle can be determined. If the final change amount of the blade installation angle can be determined, proceed to Step 5). If the final change amount of the blade installation angle cannot be determined, increase the number of improved blades and then return to Step 3).

[0042] Step 5): If the final change amount of the blade installation angle determined in Step 4) can meet other performance requirements of the compressor and the structural constraints of the compressor retrofit design, proceed to Step 7). If the final change amount of the blade installation angle determined in Step 4) cannot meet other performance requirements of the compressor or the structural constraints of the compressor retrofit design, proceed to Step 6).

[0043] Step 6): Optimize the blade profile of the improved blade according to the preset number of times. After each blade profile optimization of the improved blade, return to Step 5). If it is not possible to proceed to Step 8) after the blade profile of the improved blade has been optimized according to the preset number of times, increase the number of improved blades and then return to Step 3).

[0044] Step 7): Adjust the opening degree of the adjustable guide vane. Combine the adjusted adjustable guide vane with the determined final change amount of the blade installation angle to calculate the compressor flow rate increase rate after the guide vane is improved.

[0045] Step 8): When the compressor flow rate increase rate after the guide vane is improved reaches the second compressor flow rate increase rate target value, determine the opening degree of the adjusted adjustable guide vane and proceed to Step 9). When the compressor flow rate increase rate after the guide vane is improved does not reach the second compressor flow rate increase rate target value, return to Step 7). When it is not possible to proceed to Step 9) after adjusting the opening degree of the adjustable guide vane according to the preset number of times through Step 7), increase the number of improved blades and then return to Step 3).

[0046] Step 9): When the opening degree of the adjusted adjustable guide vane determined in Step 8), combined with the determined final change amount of the blade installation angle, meets other performance requirements of the compressor and the structural constraints of the compressor retrofit design, the design goal is achieved. When the opening degree of the adjusted adjustable guide vane determined in Step 8), combined with the determined final change amount of the blade installation angle, does not meet other performance requirements of the compressor or the structural constraints of the compressor retrofit design, return to Step 7). When it is not possible to achieve the design goal after adjusting the opening degree of the adjustable guide vane according to the preset number of times through Step 7), increase the number of improved blades and then return to Step 3).

[0047] The retrofit method of the compressor of a gas turbine in a high-temperature environment according to the present invention combines two approaches, namely improving the blades and adjusting the adjustable guide vanes, in accordance with the law of the characteristics of each stage of the multi-stage compressor changing with temperature. While ensuring the performance under ISO conditions, it effectively improves the performance of the compressor in hot weather. By using the retrofit method of the present invention, through the sensitivity analysis of the installation angle of the blades, the flow rate increase rate after the installation angle of each row of blades is changed is obtained, which can quickly determine the range and direction of blade improvement, select the row of blades that is most effective in increasing the flow rate, and improve the optimization efficiency. At the same time, compared with the method of simply increasing the opening degree of the adjustable guide vanes to increase the flow rate of the compressor in a high-temperature environment, the retrofit method of the present invention first improves and optimizes the blades, adjusts the load distribution of each stage of the compressor, reduces the load of the inlet stage under ISO conditions, provides more space for increasing the opening degree of the adjustable guide vanes in a high-temperature environment, and can also ensure the project requirements and other performance requirements of the compressor.

[0048] In this embodiment, the high-temperature environment refers to an ambient temperature greater than 28°C.

[0049] The target values of the first compressor flow rate increase rate and the second compressor flow rate increase rate in step 1) are both preset values.

[0050] The target value of the first compressor flow rate increase rate in step 1) is ξ xx_A and the target value of the second compressor flow rate increase rate is ξ xx_B ; The definitions of ξ xx_A and ξ xx_B are as follows:

[0051]

[0052]

[0053] Among them, the code of the prototype compressor is "00", the code of the retrofitted compressor is "xx", "HTC" represents the high-temperature condition of the base load, and "ISO" represents the normal-temperature condition of the base load;

[0054] m ISO_00 represents the flow rate of the prototype compressor under ISO conditions;

[0055] m HTC_00 represents the flow rate of the prototype compressor under HTC conditions;

[0056] m ISO_xx_A represents the flow rate of the compressor after only improving the blade profile under ISO conditions;

[0057] m HTC_xx_A represents the flow rate of the compressor after only improving the blade profile under HTC conditions;

[0058] m ISO_xx_BRepresents the flow rate under ISO conditions of a compressor that improves the blade profile and superimposes the improvement of the opening degree of adjustable guide vanes.

[0059] m HTC_xx_B Represents the flow rate under HTC conditions of a compressor that improves the blade profile and superimposes the improvement of the opening degree of adjustable guide vanes.

[0060] The blades in step 3 do not include adjustable guide vanes. In step 7), adjusting the opening degree of the adjustable guide vane means increasing the opening degree of the adjustable guide vane.

[0061] In step 4), adjust the change amount of the installation angle of the improved blade determined in step 3), and calculate the compressor flow rate improvement rate after the corresponding blade installation angle change through three-dimensional CFD software; when the compressor flow rate improvement rate after the blade installation angle change is greater than or equal to the first compressor flow rate improvement rate target value, then the change amount of the installation angle of the improved blade can be determined as the final change amount of the blade installation angle, and then proceed to step 5); when the compressor flow rate improvement rate after the blade installation angle change is less than the first compressor flow rate improvement rate target value, then after increasing the number of improved blades, return to step 3). Calculating the compressor flow rate improvement rate after the corresponding blade installation angle change through three-dimensional CFD software can facilitate the determination of the final change amount of the blade installation angle.

[0062] Add the following steps between step 3) and step 4):

[0063] Calculate the compressor flow rate improvement rate after the corresponding blade installation angle change by the one-dimensional average streamline calculation method for the change amount of the installation angle of the improved blade determined in step 3), to judge whether the preliminary change amount of the blade installation angle can be determined. If the compressor flow rate improvement rate after the corresponding blade installation angle change calculated by the one-dimensional average streamline calculation method is greater than or equal to the first compressor flow rate improvement rate target value, the preliminary change amount of the blade installation angle can be determined, and then proceed to step 4); if the compressor flow rate improvement rate after the corresponding blade installation angle change calculated by the one-dimensional average streamline calculation method is less than the first compressor flow rate improvement rate target value, the preliminary change amount of the blade installation angle cannot be determined, and then after increasing the number of improved blades, return to step 3). Before obtaining the final change amount of the blade installation angle, first calculate the compressor flow rate improvement rate after the corresponding blade installation angle change by the one-dimensional average streamline calculation method, so that the preliminary change amount of the blade installation angle can be determined first. In the subsequent step 4), determine the final change amount of the blade installation angle according to the change amount of the installation angle of the improved blade and the preliminary change amount of the blade installation angle determined in step 3), which can improve the efficiency.

[0064] The sensitivity analysis of the installation angle of the blade in step 2) includes the following steps:

[0065] 2a), Calculate the flow rate mISO_00 under the ISO condition of the prototype compressor and the flow rate m under the HTC condition of the prototype compressor by using the one-dimensional average streamline calculation method. HTC_00 ;

[0066] 2b), Set the installation angle of the first-stage rotor blade to be reduced by α degrees, and keep the other rotor blades the same as those of the prototype compressor. Then, use the one-dimensional average streamline calculation method to calculate the flow rate m ISO_1-α under the ISO condition of the compressor after the installation angle of the first-stage rotor blade is reduced by α degrees and the flow rate m HTC_1-α under the HTC condition of the compressor after the installation angle of the first-stage rotor blade is reduced by α degrees.

[0067] 2c), Refer to the operation method for the first-stage rotor blade in 2b), gradually reduce the installation angle of the rotor blade by α degrees row by row, keep the other rotor blades the same as those of the prototype compressor, and then use the one-dimensional average streamline calculation method to calculate the flow rate m ISO_n-α under the ISO condition of the compressor after the installation angle of the nth-stage rotor blade is reduced by α degrees and the flow rate m HTC_n-α under the HTC condition of the compressor.

[0068] Calculate the flow rate increase rate ξ stg-α_n for each row of rotor blades after the installation angle is reduced according to the following formula:

[0069]

[0070] 2d), Gradually increase the installation angle of each row of rotor blades by α degrees. According to the same operation in 3c), use the one-dimensional average streamline calculation method to calculate the flow rate m ISO_n+α under the ISO condition of the compressor after the installation angle of the nth-stage rotor blade is increased by α degrees and the flow rate m HTC_n+α under the HTC condition of the compressor; calculate the flow rate increase rate ξ stg+α_n for each row of rotor blades after the installation angle is increased. The formula is as follows:

[0071]

[0072] 3e), Gradually reduce the installation angle of each row of stator blades by α degrees. According to the same operation in 2b) and 2c), calculate the flow rate increase rate for each row of stator blades after the installation angle is reduced; gradually increase the installation angle of each row of stator blades by α degrees. According to the same operation in 2d), calculate the flow rate increase rate for each row of stator blades after the installation angle is increased.

[0073] By performing a sensitivity analysis on the installation angle of the blades, the flow rate increase rate after the installation angle of each row of blades is changed by the same α degrees can be obtained, which can quickly determine the range and direction of the improved blades, select the row of blades that is most effective in increasing the flow rate, and improve the optimization efficiency.

[0074] If ξ stg-α_nIf it is greater than 0, it indicates that reducing the installation angle of the blades in this row by α degrees has a positive gain in improving the performance in high-temperature weather, and the greater the value, the more significant the positive gain effect; conversely, if ξ stg-α_n is less than 0, it indicates that reducing the installation angle of the blades in this row by α degrees has a negative impact on improving the performance in high-temperature weather, and the smaller the value, the more significant the negative impact effect.

[0075] In step 2), the flow rate increase rates after changing the installation angles of each row of blades are sorted according to the absolute values of the numerical values, that is, the absolute values of the numerical values of the flow rate increase rates after reducing the installation angles of the moving blades in each row, the absolute values of the numerical values of the flow rate increase rates after increasing the installation angles of the moving blades in each row, the absolute values of the numerical values of the flow rate increase rates after reducing the installation angles of the stationary blades in each row, and the flow rate increase rates after increasing the installation angles of the stationary blades in each row are sorted according to the absolute values of the numerical values.

[0076] The α degree in step 2) is generally 2° - 3°. In this embodiment, the α degree is 2°. After obtaining the sorting of the flow rate increase rates after changing the installation angles of each row of blades according to the absolute values of the numerical values, the greater the absolute value in the sorting of the absolute values of the numerical values, the stronger the sensitivity of the corresponding blade installation angle, and the more suitable for improvement. Select the blades with the absolute values of the numerical values ranked before the preset ranking as the initial improved blades. Step 3) can be used to determine the number of improved blades, that is, to determine which blades are used as the improved blades.

[0077] In the step added between step 3) and step 4): Adjusting the installation angle change amount of the improved blades determined in step 3) means assigning values to the installation angles of the improved blades determined in each step 3) within the preset installation angle adjustment range, and calculating the compressor flow rate increase rate after the corresponding blade installation angle change through the one-dimensional average streamline calculation method to determine the preliminary blade installation angle change amount; in the subsequent step 4), according to the installation angle change amount of the improved blades determined in step 3) and the preliminary blade installation angle change amount, the installation angle change amount of the improved blades is assigned again, and the compressor flow rate increase rate after the corresponding blade installation angle change is calculated through the three-dimensional CFD software to determine the final blade installation angle change amount.

[0078] The project requirements in step 3) include the retrofit and upgrade cost and the project cycle. When the number of improved blades meets the preset retrofit and upgrade cost and project cycle, step 4) is carried out; when the number of improved blades does not meet the preset retrofit and upgrade cost or project cycle, the number of improved blades is reduced by several rows so that the number of improved blades meets the project requirements, and step 4) is carried out. Through step 3), the number of improved blades can meet the requirements of the project budget and time. The project requirements also include the optimization goal, and the optimization goal is a value higher than the first compressor flow rate increase rate target value to increase the sensitivity requirement for the improved blades.

[0079] Other performance requirements of the compressor include the pressure ratio, efficiency, and surge margin of the compressor. In step 5), according to the final blade setting angle change determined in step 4), the analysis data of the overall compressor flow field after improving the blade is calculated through 3D CFD software. The analysis data of the overall compressor flow field after improving the blade includes other performance and structural changes of the compressor after improving the blade. If the analysis data of the overall compressor flow field after improving the blade can meet the other performance requirements of the compressor and the structural constraints of the compressor retrofit design, then step 7) is carried out. If the analysis data of the overall compressor flow field after improving the blade cannot meet the other performance requirements of the compressor or the structural constraints of the compressor retrofit design, then step 6) is carried out.

[0080] Since multiple sets of final blade setting angle changes can be obtained through step 4), there can be multiple sets of analysis data of the overall compressor flow field after improving the blade; among the multiple sets of analysis data of the overall compressor flow field after improving the blade, the data with the best other performance indicators of the compressor is selected, and the corresponding final blade setting angle change is selected as the determined blade setting angle change, and then enter the subsequent steps.

[0081] When the structural constraint in the compressor retrofit design requires that the compressor disk is not changed, then in the range of 15% - 100% of the blade height of the improved blade, rotate the corresponding angle according to the final blade setting angle change. Starting from 15% of the blade height of the improved blade, the installation angle linearly transitions to the 0% blade height section. The installation angle of the 0% blade height section of the improved blade is the same as the original blade profile, so that the structure of the improved blade meets the structural constraints of the compressor retrofit design.

[0082] The airfoil optimization of the improved blade in step 6) includes one or more of the following improvement methods:

[0083] 6a) Improve the profile of the pressure surface of the preset section of the blade;

[0084] 6b) Improve the profile of the suction surface of the preset section of the blade;

[0085] 6c) Improve the thickness distribution of the blade;

[0086] 6d) Improve the leading edge shape of the blade.

[0087] The airfoil optimization is determined according to actual needs.

[0088] Add the following steps between step 1) and step 2): Calculate the flow rate of the prototype compressor under ISO conditions and HTC conditions using 3D CFD software; Calculate the other performance requirements of the prototype compressor under ISO conditions and HTC conditions using 3D CFD software. Calculate various parameters in advance to improve the design efficiency.

[0089] In summary, the present invention effectively overcomes various drawbacks in the prior art and has high industrial utilization value.

[0090] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A modification method for a compressor of a gas turbine in a high-temperature environment, characterized in that, it includes the following steps: Step 1), determine the structural constraints for the compressor modification design, the target value of the first compressor flow rate increase rate after only improving the blade profile, and the target value of the second compressor flow rate increase rate after improving the blade profile and superimposing the improvement of the adjustable guide vane opening; the blades include moving blades and stationary blades; Step 2), according to the sensitivity analysis of the installation angle of the blades, obtain the flow rate increase rate after the installation angle of each row of blades is changed, and sort the flow rate increase rates after the installation angle of each row of blades is changed in descending order of the absolute value of the numerical value; Among each row of blades, the blades with the flow rate increase rate after the installation angle is changed greater than the target value of the first compressor flow rate increase rate and the absolute value of the numerical value ranking before the preset ranking are used as the initial improved blades; Step 3), evaluate whether the number of improved blades meets the project requirements. When the number of improved blades meets the preset project requirements, proceed to Step 4); When the number of improved blades does not meet the project requirements, reduce the number of improved blades by several rows so that the number of improved blades meets the project requirements, and proceed to Step 4); When initially evaluating whether the number of improved blades meets the project requirements, the number of improved blades is the number of the initial improved blades in Step 2); Step 4), adjust the change amount of the installation angle of the improved blades determined in Step 3) to judge whether the final change amount of the blade installation angle can be determined; If the final change amount of the blade installation angle can be determined, proceed to Step 5); if the final change amount of the blade installation angle cannot be determined, increase the number of improved blades and then return to Step 3); Step 5), if the final change amount of the blade installation angle determined in Step 4) can meet the other performance requirements of the compressor and the structural constraints of the compressor modification design, proceed to Step 7); if the final change amount of the blade installation angle determined in Step 4) cannot meet the other performance requirements of the compressor or the structural constraints of the compressor modification design, proceed to Step 6); Step 6), optimize the blade profile of the improved blades according to the preset number of times; After each optimization of the blade profile of the improved blades, return to Step 5); If after optimizing the blade profile of the improved blades according to the preset number of times, Step 8) cannot be performed, increase the number of improved blades and then return to Step 3); Step 7), adjust the opening of the adjustable guide vane; Combine the adjusted adjustable guide vane with the determined final change amount of the blade installation angle to calculate the compressor flow rate increase rate after improving the guide vane; Step 8), when the compressor flow rate increase rate after improving the guide vane reaches the target value of the second compressor flow rate increase rate, determine the opening of the adjusted adjustable guide vane and proceed to Step 9); When the compressor flow rate increase rate after improving the guide vane does not reach the target value of the second compressor flow rate increase rate, return to Step 7); When after adjusting the opening of the adjustable guide vane according to the preset number of times through Step 7), Step 9) cannot be performed, increase the number of improved blades and then return to Step 3); Step 9), when the opening of the adjustable guide vane after adjustment determined in step 8), combined with the determined final blade installation angle change, meets other performance requirements of the compressor and the structural constraints of the compressor modification design, the design goal is achieved; when the opening of the adjustable guide vane after adjustment determined in step 8), combined with the determined final blade installation angle change, does not meet other performance requirements of the compressor or the structural constraints of the compressor modification design, return to step 7); when the design goal cannot be achieved after adjusting the opening of the adjustable guide vane for a preset number of times through step 7), increase the number of improved blades and return to step 3).

2. The method for modifying a gas turbine compressor for a high temperature environment according to claim 1, Features: In step 4), the installation angle variation of the improved blade determined in step 3) is adjusted, and the compressor flow rate increase rate after the corresponding blade installation angle is changed is calculated by three-dimensional CFD software; when the compressor flow rate increase rate after the blade installation angle is changed is greater than or equal to the first compressor flow rate increase rate target value, the installation angle variation of the improved blade can be determined as the final blade installation angle variation, and step 5) is performed; When the compressor flow rate increase rate after the blade installation angle is changed is less than the first compressor flow rate increase rate target value, the number of improved blades is increased and the process returns to step 3).

3. The method for modifying a gas turbine compressor for a high temperature environment according to claim 1, Features: Add the following steps between step 3) and step 4): The installation angle change of the improved blade determined in step 3) is calculated by a one-dimensional average streamline calculation method to obtain a corresponding compressor flow rate increase rate after the blade installation angle is changed, so as to determine whether a preliminary blade installation angle change can be determined. If the compressor flow rate increase rate after the blade installation angle is changed calculated by the one-dimensional average streamline calculation method is greater than or equal to the first compressor flow rate increase rate target value, the preliminary blade installation angle change can be determined, and step 4) is performed; If the compressor flow rate increase rate after the corresponding blade installation angle change calculated by the one-dimensional average streamline calculation method is less than the first compressor flow rate increase rate target value, the initial blade installation angle change cannot be determined, and the number of improved blades must be increased and then return to step 3).

4. The method for modifying a gas turbine compressor for a high temperature environment according to claim 1, Features: The sensitivity analysis of the installation angle of the blade in step 2) includes the following steps: 2a), Calculate the flow rate m under the ISO condition of the prototype compressor using the one-dimensional average streamline calculation method ISO_00 and the flow rate m under the HTC condition of the prototype compressor HTC_00 ; 2b), set the installation angle of the first-stage moving blade to decrease by α degrees, and the remaining moving blades remain the same as the prototype compressor. Then, use the one-dimensional average streamline calculation method to calculate the flow rate m under the ISO condition of the compressor after the installation angle of the first-stage moving blade is decreased by α degrees ISO_1-α and the flow rate m under the HTC condition of the compressor after the installation angle of the first-stage moving blade is decreased by α degrees HTC_1-α ; 2c), referring to the operation method of the first-stage rotor blades in 2b), gradually reduce the installation angle α of the rotor blades row by row. Keep the other rotor blades consistent with the prototype compressor. Then, use the one-dimensional average streamline calculation method to calculate the compressor flow rate m under the ISO condition after the installation angle of the nth-stage rotor blades is reduced by α ISO_n-α and the compressor flow rate m HTC_n-α ; According to the following formula, calculate the flow rate increase rate ξ after the installation angle of each row of moving blades is reduced respectively stg-α_n : 2d), successively increase the installation angles of each row of moving blades by α degrees, and perform the same operations as in 2c) above. Use the one-dimensional average streamline calculation method to calculate the compressor flow rate m under the ISO condition after the installation angle of the nth-stage moving blade is increased by α degrees ISO_n+α and the compressor flow rate m under the HTC condition HTC_n+α ; respectively calculate the flow rate increase rate ξ after the installation angles of each row of moving blades are increased stg+α_n , and the formula is as follows: 2e), reduce the installation angle of each row of stator blades by α degrees in turn, and follow the same operations as 2b) and 2c) to calculate the flow increase rate after the installation angle of each row of stator blades is reduced; increase the installation angle of each row of stator blades by α degrees in turn, and follow the same operations as 2d) to calculate the flow increase rate after the installation angle of each row of stator blades is increased.

5. The method for modifying a gas turbine compressor for a high temperature environment according to claim 1, Features: In step 2), the flow rate increase rates after the installation angles of each row of blades are changed are sorted according to the absolute values of the numerical values, that is, the absolute values of the flow rate increase rates after the installation angles of each row of moving blades are reduced, the absolute values of the flow rate increase rates after the installation angles of each row of moving blades are increased, the absolute values of the flow rate increase rates after the installation angles of each row of stationary blades are reduced, and the flow rate increase rates after the installation angles of each row of stationary blades are increased are sorted according to the absolute values of the numerical values, in descending order of the absolute values.

6. The retrofit method of a gas turbine compressor in a high-temperature environment according to claim 1, characterized in that: The project requirements in step 3) include retrofit and upgrade costs and project cycle.

7. The retrofit method of a gas turbine compressor in a high-temperature environment according to claim 1, characterized in that: Other performance requirements of the compressor include the pressure ratio, efficiency, and surge margin of the compressor.

8. The retrofit method of a gas turbine compressor in a high-temperature environment according to claim 1, characterized in that: When the structural constraint in the retrofit design of the compressor requires that the compressor disk is not changed, then in the range of 15% - 100% of the blade height of the improved blade, it rotates by a corresponding angle according to the final change amount of the blade installation angle. Starting from 15% of the blade height of the improved blade, the installation angle linearly transitions to the 0% blade height section, and the installation angle of the 0% blade height section of the improved blade is the same as the original blade profile.

9. The retrofit method of a gas turbine compressor in a high-temperature environment according to claim 1, characterized in that: The following steps are added between step 1) and step 2): Using three-dimensional CFD software to calculate the flow rate of the prototype compressor under ISO conditions and HTC conditions; Using three-dimensional CFD software to calculate other performance requirements of the prototype compressor under ISO conditions and HTC conditions.

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