Simulation method for constructing high-pressure turbine throat flow of gas turbine

Abstract

This application belongs to the field of high-pressure turbine design, and specifically relates to a simulation method for calculating the throat flow rate of a gas turbine. The method involves splitting the throat section and the high-pressure turbine guide vane outlet section, calculating the section parameters of the throat section first using an air ratio, and then calculating the section parameters of the high-pressure turbine guide vane outlet section. The equivalent throat flow rate is calculated using the throat section parameters, and the high-pressure turbine power is calculated using the high-pressure turbine guide vane outlet section parameters. The equivalent throat flow rate and high-pressure turbine power are then substituted into the high-pressure turbine rotor inlet flow balance equation and power balance equation to perform off-design point calculations, obtaining simulation results of the overall turbine performance based on accurate high-pressure turbine throat flow rate. This method overcomes the shortcomings of traditional simulations that assume all cold air enters the throat front end. It splits the original 41-section model, calculating the two-stage section parameters step-by-step, achieving a layered and accurate solution for the throat flow rate and guide vane outlet parameters.

Description

Technical Field

[0001] This application belongs to the field of high-pressure turbine design, and specifically relates to a simulation method for the flow rate at the throat of a high-pressure turbine in a gas turbine. Background Technology

[0002] Currently, Gasturb software is the most widely used and applied software for overall performance analysis of gas turbines. Many domestic overall performance simulation software programs use this software as a reference for building gas turbine models.

[0003] The drawback of existing simulation methods is that they assume that all the cooling air in the high-pressure turbine guide vane, including the upper and lower edge plates, enters before the throat of the high-pressure turbine guide vane, which does not match the actual air flow pattern at the guide vane of a gas turbine. As a result, the overall performance parameters obtained by simulation in this way deviate significantly from the experimental data.

[0004] Therefore, obtaining more accurate performance parameters for high-pressure turbine guide vanes is a problem that needs to be solved. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a simulation method for the flow rate at the throat of a high-pressure turbine in a gas turbine, thereby resolving the problem of significant discrepancies between the overall performance parameters of the high-pressure turbine guide vane obtained from simulations and experimental data in the prior art.

[0006] The technical solution of this application is: a simulation method for constructing the flow rate at the throat of a high-pressure turbine in a gas turbine, comprising:

[0007] Determine the proportion of cooling air leaking into the throat of the high-pressure turbine guide vane. ;

[0008] The 41 section of the high-pressure turbine guide vane is decomposed to form the throat section and the high-pressure turbine guide vane outlet section, combined with the air ratio. First calculate the cross-sectional parameters of the throat section, then calculate the cross-sectional parameters of the outlet section of the high-pressure turbine guide.

[0009] The equivalent flow rate of the throat is calculated using the cross-sectional parameters of the throat section, and the power of the high-pressure turbine is calculated using the cross-sectional parameters of the outlet section of the high-pressure turbine guide vane.

[0010] Substituting the throat flow rate and high-pressure turbine power into the high-pressure turbine rotor inlet flow balance equation and power balance equation, non-design point calculations are performed to obtain the overall performance simulation results based on the accurate high-pressure turbine throat flow rate.

[0011] Preferably, the cross-sectional parameters of the throat section include the throat section flow rate, the throat section total temperature, and the throat section total pressure, wherein:

[0012] Throat cross-sectional flow The calculation formula is:

[0013] ;

[0014] in, The flow rate at the combustion chamber outlet section is... The bleed air flow rate for the high-pressure turbine guide vane;

[0015] Total temperature of throat section The calculation formula is:

[0016] ;

[0017] in, The total temperature at the combustion chamber outlet section. The fuel-air ratio at the combustion chamber outlet section is [value missing]. High-pressure turbine guide vane bleed air temperature;

[0018] Total pressure of throat section The calculation formula is:

[0019] ;

[0020] ;

[0021] In the formula, For the pressure loss of the high-pressure turbine guide vane, The total pressure at the combustion chamber outlet section. For fuel flow rate, The oil-gas ratio at the outlet section of the high-pressure turbine guide vane.

[0022] Preferably, the cross-sectional parameters of the outlet section of the high-pressure turbine guide vane include the outlet section flow rate, the total temperature of the outlet section, and the total pressure of the outlet section, wherein:

[0023] Outlet cross-sectional flow The calculation formula is:

[0024] ;

[0025] Total temperature at the outlet section The calculation formula is:

[0026] ;

[0027] in, The oil-gas ratio at the throat cross-section;

[0028] Total pressure at the outlet section The calculation formula is:

[0029] ;

[0030] ;

[0031] in, The oil-gas ratio at the outlet section of the high-pressure turbine guide vane.

[0032] Preferably, the formula for calculating the throat equivalent flow rate is:

[0033] ;

[0034] In the formula, The converted flow rate is the flow rate of the throat section.

[0035] Preferably, the high-pressure turbine power The calculation formula is:

[0036] ;

[0037] In the formula, The expansion ratio of the high-pressure turbine. This refers to the efficiency of the high-pressure turbine.

[0038] Preferably, the cross-sectional parameters of the throat section are mixed with the leakage parameters of the guide to obtain the cross-sectional parameters of the outlet section of the high-pressure turbine guide.

[0039] The simulation method for high-pressure turbine throat flow in this gas turbine construction method has the following advantages:

[0040] By first determining the leakage ratio of the cooling air throat, and closely aligning with the actual airflow pattern of the high-pressure turbine guide vane, the model overcomes the shortcomings of traditional simulations that assume all cooling air enters the throat front end. The original 41-section is split into two parts for modeling, and the parameters of the two sections are calculated step-by-step, achieving precise layered solutions for throat flow rate and guide vane outlet parameters.

[0041] By relying on the throat-converted flow rate and high-pressure turbine power to establish a combined flow and power balance equation for off-design point calculations, the accuracy of gas turbine overall performance simulation is significantly improved, the deviation between simulation results and experimental data is reduced, and the reliability of component matching calculations under varying operating conditions and off-design points is ensured.

[0042] It better reflects the actual gas flow at the high-pressure turbine guide vane, and the resulting model simulation results are closer to the actual engineering situation. This can improve the accuracy of the whole machine simulation model. At the same time, it can evaluate the impact of cold gas leakage from the high-pressure turbine guide vane on the overall performance parameters. Attached Figure Description

[0043] Figure 1 This is a schematic diagram showing the location of the throat of the high-pressure turbine guide vane.

[0044] Figure 2 This is a schematic diagram of a single-rotor, dual-shaft gas turbine.

[0045] Figure 3 This is a schematic diagram of the overall process of this application. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some, not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0047] The minimum exhaust edge area in the converging channel of the guide vane through which the gas flows is the throat area of ​​the guide vane. A schematic diagram of the throat location of the high-pressure turbine guide vane is shown below. Figure 1 The drawback of existing simulation methods is that they assume all the cooling air for the high-pressure turbine guide vanes, including the upper and lower edge plates, enters before the throat of the high-pressure turbine guide vanes, which does not match the actual airflow pattern at the guide vanes of gas turbines. Given the existing arrangement of the cooling air vents in the high-pressure turbine guide vanes of a certain type of gas turbine, a portion of the air must inevitably be discharged into the main airflow after the throat.

[0048] According to the working principle of gas turbines, the combustion chamber outlet temperature is the highest temperature of each section of the gas turbine. High-temperature and high-pressure gas passes through the first-stage guide vane of the high-pressure turbine and usually enters the critical state very early, that is, the equivalent flow rate of the critical section remains unchanged. Therefore, the parameters of the critical state are very critical and directly affect the accuracy of the overall performance evaluation.

[0049] Currently, combined with Figure 2 In existing gas turbine simulation software, the converted flow rate of the 41 (original) section (high pressure turbine guide vane outlet) is used as the throat flow rate for calculation. However, in actual operation, air leakage occurs at the tail edge and front of the upper and lower edge plates of the guide vane, causing some air to enter the front of the high pressure turbine rotor directly without passing through the throat, which affects the matching relationship of the engine.

[0050] Based on the above principles, a simulation method for constructing the high-pressure turbine throat flow in a gas turbine is designed, such as... Figure 3 Specifically, it includes the following steps:

[0051] Step S100: Determine the proportion of cooling air leaking from the high-pressure turbine guide vane into the throat. , It can be obtained through actual experimental data.

[0052] Step S200: Decompose the 41 section of the high-pressure turbine guide vane to form the throat section and the high-pressure turbine guide vane outlet section, and combine the air ratio... First calculate the cross-sectional parameters of the throat section, then calculate the cross-sectional parameters of the high-pressure turbine guide vane outlet section. Section 41 is the original cross-section of the high-pressure turbine guide vane outlet.

[0053] Preferably, the cross-sectional parameters of the throat section include the throat section flow rate, the throat section total temperature, and the throat section total pressure, wherein:

[0054] Throat cross-sectional flow The calculation formula is:

[0055] ;

[0056] in, The flow rate at the combustion chamber outlet section is... The bleed air flow rate for the high-pressure turbine guide vane;

[0057] Total temperature of throat section The calculation formula is:

[0058] ;

[0059] in, The total temperature at the combustion chamber outlet section. The fuel-air ratio at the combustion chamber outlet section is [value missing]. High-pressure turbine guide vane bleed air temperature;

[0060] Total pressure of throat section The calculation formula is:

[0061] ;

[0062] ;

[0063] In the formula, For the pressure loss of the high-pressure turbine guide vane, The total pressure at the combustion chamber outlet section. For fuel flow rate, The oil-gas ratio at the outlet section of the high-pressure turbine guide vane.

[0064] The cross-sectional parameters of the high-pressure turbine guide vane outlet section include outlet cross-sectional flow rate, outlet cross-sectional total temperature, and outlet cross-sectional total pressure, where:

[0065] Outlet cross-sectional flow The calculation formula is:

[0066] ;

[0067] Total temperature at the outlet section The calculation formula is:

[0068] ;

[0069] in, The oil-gas ratio at the throat cross-section;

[0070] Total pressure at the outlet section The calculation formula is:

[0071] ;

[0072] ;

[0073] in, The oil-gas ratio at the outlet section of the high-pressure turbine guide vane.

[0074] Preferably, the cross-sectional parameters of the throat section are mixed with the leakage parameters of the guide vane to obtain the cross-sectional parameters of the high-pressure turbine guide vane outlet section. By accurately reproducing the mixing process of the main airflow in the throat with the leaked cold air from the trailing edge and upper and lower edge plates, the aerodynamic parameters of the guide vane outlet are made to better match the actual flow state of the machine, ensuring the authenticity of the overall simulation results from the process level.

[0075] In step S300, the throat equivalent flow rate is calculated using the cross-sectional parameters of the throat section, and the high-pressure turbine power is calculated using the cross-sectional parameters of the high-pressure turbine guide vane outlet section.

[0076] Preferably, the formula for calculating the throat equivalent flow rate is:

[0077] ;

[0078] In the formula, The converted flow rate is the flow rate of the throat section.

[0079] High-pressure turbine power The calculation formula is:

[0080] ;

[0081] In the formula, The expansion ratio of the high-pressure turbine. This refers to the efficiency of the high-pressure turbine.

[0082] In step S400, the throat-converted flow rate and high-pressure turbine power are substituted into the high-pressure turbine rotor inlet flow balance equation and power balance equation (high-pressure turbine power equals compressor power) to perform non-design point calculations and obtain the overall machine performance simulation results based on the accurate high-pressure turbine throat flow rate.

[0083] In summary, this application has the following advantages:

[0084] By first determining the leakage ratio of the cooling air throat, and closely aligning with the actual airflow pattern of the high-pressure turbine guide vane, the model overcomes the shortcomings of traditional simulations that assume all cooling air enters the throat front end. The original 41-section is split into two parts for modeling, and the parameters of the two sections are calculated step-by-step, achieving precise layered solutions for throat flow rate and guide vane outlet parameters.

[0085] By relying on the throat-converted flow rate and high-pressure turbine power to establish a combined flow and power balance equation for off-design point calculations, the accuracy of gas turbine overall performance simulation is significantly improved, the deviation between simulation results and experimental data is reduced, and the reliability of component matching calculations under varying operating conditions and off-design points is ensured.

[0086] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A simulation method for the flow rate at the throat of a high-pressure turbine in a gas turbine, characterized in that, include: Determine the proportion of cooling air leaking into the throat of the high-pressure turbine guide vane. ; The 41 section of the high-pressure turbine guide vane is decomposed to form the throat section and the high-pressure turbine guide vane outlet section, combined with the air ratio. First calculate the cross-sectional parameters of the throat section, then calculate the cross-sectional parameters of the outlet section of the high-pressure turbine guide. The equivalent flow rate of the throat is calculated using the cross-sectional parameters of the throat section, and the power of the high-pressure turbine is calculated using the cross-sectional parameters of the outlet section of the high-pressure turbine guide vane. Substituting the throat flow rate and high-pressure turbine power into the high-pressure turbine rotor inlet flow balance equation and power balance equation, non-design point calculations are performed to obtain the overall performance simulation results based on the accurate high-pressure turbine throat flow rate.

2. The simulation method for high-pressure turbine throat flow in a gas turbine as described in claim 1, characterized in that, The cross-sectional parameters of the throat section include the throat section flow rate, the throat section total temperature, and the throat section total pressure, wherein: Throat cross-sectional flow The calculation formula is: ； in, The flow rate at the combustion chamber outlet section is... The bleed air flow rate for the high-pressure turbine guide vane; Total temperature of throat section The calculation formula is: ； in, The total temperature at the combustion chamber outlet section. The fuel-air ratio at the combustion chamber outlet section is [value missing]. High-pressure turbine guide vane bleed air temperature; Total pressure of throat section The calculation formula is: ； ； In the formula, For the pressure loss of the high-pressure turbine guide vane, The total pressure at the combustion chamber outlet section. For fuel flow rate, The oil-gas ratio at the outlet section of the high-pressure turbine guide vane.

3. The simulation method for high-pressure turbine throat flow in a gas turbine as described in claim 2, characterized in that, The cross-sectional parameters of the outlet section of the high-pressure turbine guide vane include the outlet section flow rate, the total temperature of the outlet section, and the total pressure of the outlet section, wherein: Outlet cross-sectional flow The calculation formula is: ； Total temperature at the outlet section The calculation formula is: ； in, The oil-gas ratio at the throat cross-section; Total pressure at the outlet section The calculation formula is: ； ； in, The oil-gas ratio at the outlet section of the high-pressure turbine guide vane.

4. The simulation method for high-pressure turbine throat flow in a gas turbine as described in claim 3, characterized in that, The formula for calculating the throat equivalent flow rate is: ； In the formula, The converted flow rate is the flow rate of the throat section.

5. The simulation method for high-pressure turbine throat flow in a gas turbine as described in claim 3, characterized in that, The high-pressure turbine power The calculation formula is: ； In the formula, The expansion ratio of the high-pressure turbine. This refers to the efficiency of the high-pressure turbine.

6. The simulation method for high-pressure turbine throat flow in a gas turbine as described in claim 1, characterized in that, The cross-sectional parameters of the throat section are mixed with the leakage parameters of the guide to obtain the cross-sectional parameters of the outlet section of the high-pressure turbine guide.

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