Similar modeling adaptive design method for large-flow compressed air energy storage compressor

Abstract

The invention discloses a similar modeling adaptive design method for a large-flow compressed air energy storage compressor, and belongs to the field of centrifugal rotating fluid machinery. The method comprises a stage matching part and a similar conversion part, specifically, in the stage matching part, relevant parameters of carbon dioxide are given, and matching parameters of all stages of the multistage carbon dioxide centrifugal compressor are determined; in the similar conversion part, the mass flow and the rotating speed corresponding to the single-stage carbon dioxide centrifugal compressor of a series of flow coefficients are calculated through a similar modeling method based on the stage matching result; and comparing the design requirements of the multi-stage carbon dioxide centrifugal compressor, determining the flow coefficient of each stage of the multi-stage carbon dioxide centrifugal compressor, and finally connecting in series to form the multi-stage centrifugal compressor for performance calculation. According to the method, multiple factors such as gas characteristics, similar conversion criteria, interstage matching, variable working condition adaptability and structural reliability are comprehensively considered, and efficient and stable operation of the centrifugal compressor in different use scenes is ensured.

Description

Technical Field

[0001] The invention relates to a similar modeling adaptation design method for a large-flow compressed air energy storage compressor, and belongs to the field of centrifugal rotating fluid machinery. Background Art

[0002] In today's global efforts to reduce greenhouse gas emissions and promote sustainable development, the capture, utilization and storage technology of carbon dioxide is particularly important. Multi-stage centrifugal compressors play an indispensable role in this process. Multi-stage centrifugal compressors gradually compress the gas through a series of impellers. Each stage of the impeller increases the speed of the gas, and then decelerates in the diffuser to convert kinetic energy into pressure energy. After multiple levels of compression, the pressure of the gas is significantly increased. Multi-stage centrifugal compressors have an efficient compression mechanism, good adaptability and high reliability. Similar conversion of compressors is usually carried out between the same working fluids. Therefore, solving the similar conversion problem between different working fluids faces great challenges. When converting an air compressor to a carbon dioxide compressor, the differences in the physical properties of the two working fluids must be considered, such as density, adiabatic coefficient and compression factor, which have an important impact on the design parameters and performance of the compressor. For multi-stage compressors, before performing similar conversion, it is necessary to derive the similar conversion conditions of each stage based on flow theory and the gas properties of carbon dioxide, and determine the flow coefficient corresponding to each stage of the compressor according to the given parameters. Multi-stage centrifugal compressors not only perform well in traditional industrial applications, but also play a vital role in carbon dioxide management, a key area in addressing climate change and supporting sustainable development. Through precise similar modular design, it can ensure that the compressor remains efficient and stable when handling different working fluids, further enhancing its industrial value and social benefits. Summary of the invention

[0003] The present invention aims to solve the problem that existing large-flow compressed air energy storage compressors are difficult to flexibly cope with various operating conditions. An adaptation design method based on similarity modeling is proposed to convert a centrifugal compressor originally designed for air into a compressor suitable for carbon dioxide compression.

[0004] The technical solution adopted to achieve the purpose of the present invention is: a similar modeling adaptation design method for a large-flow compressed air energy storage compressor, comprising the following steps:

[0005] Step 1 gives the key design parameters of the multi-stage carbon dioxide centrifugal compressor, including inlet and outlet temperatures and pressures.

[0006] Step 2 Combined with the inlet and outlet temperatures, the inlet temperature T of each stage of the multi-stage carbon dioxide centrifugal compressor is determined using a step-by-step arithmetic progression. i

[0007] Step 3: Based on the BWRS equation, the aerodynamic thermodynamic parameters of carbon dioxide are derived, and then the inlet pressure and pressure ratio of each stage of the carbon dioxide centrifugal compressor are obtained.

[0008] Step 4: In order to design a CO2 compressor that meets specific target parameters, a series of geometrically similar single-stage air centrifugal compressor design parameters are used. For a single-stage CO2 centrifugal compressor under given operating conditions, the mass flow similarity parameter Π m Similarity parameter Π with tip speed u , similar conversions are made for the mass flow rates and rotation speeds of air and carbon dioxide.

[0009] Step 5: Based on the comparison between the calculated results and the given CO2 target parameters, the shaft diameter is finally locked to 1.2D.

[0010] Step 6 realizes the gradual series connection from single stage to multi-stage based on the flow field and optimization results, ensuring that the design of each step is within the allowable error range.

[0011] The method specifically comprises the following steps:

[0012] Step 1: Given the key design parameters of the multi-stage carbon dioxide centrifugal compressor, including the multi-stage inlet total temperature T in , multi-stage inlet total pressure P in , multi-stage outlet total temperature T out , multi-stage outlet total pressure P out ;

[0013] Step 2: According to the parameters given in step 1, determine the inlet temperature of each stage of the multi-stage carbon dioxide centrifugal compressor. The inlet temperature of each stage is set as an arithmetic progression that decreases step by step. Given that the number of stages of the multi-stage carbon dioxide centrifugal compressor is k, the calculation formula for the inlet temperature of each stage is as follows:

[0014]

[0015] Among them, T i represents the inlet temperature of the i-th stage, 0<i<k+1;

[0016] Therefore, the inlet temperature T of each stage of the multi-stage carbon dioxide centrifugal compressor is obtained. i ;

[0017] Step 3: After the number of stages is determined, the pressure ratio of each stage is further determined according to the ratio of the inlet temperatures of each stage; therefore, according to the results calculated in step 2, the inlet pressure and pressure ratio of each stage of the multi-stage carbon dioxide centrifugal compressor are determined; based on the BWRS equation, the aerodynamic thermodynamic parameters of carbon dioxide can be derived, which is an analytical model of pressure P, and the specific form is as follows:

[0018]

[0019] Wherein, P represents pressure, kPa; T represents temperature, K; Indicates the density of the gas, kmol / m 3 ; R is the universal gas constant, symbol are the empirical parameters of the BWRS equation; the solution of the aerodynamic thermodynamic parameters of carbon dioxide can be divided into the following sub-steps:

[0020] Step 3-1: Solve for the density of carbon dioxide and rewrite the formula in step 3 as follows:

[0021]

[0022] The density is solved by the secant method, and the iterative formula is as follows:

[0023]

[0024] Initial value , ;

[0025] Step 3-2: Calculate the compression factor Z of carbon dioxide using the following formula:

[0026]

[0027] Step 3-3: Calculate the constant volume specific heat capacity c of carbon dioxide v , the calculation formula is as follows:

[0028]

[0029] In the formula, Indicates molecular weight, is the density under standard conditions;

[0030] Step 3-4: Calculate the constant pressure specific heat capacity c of carbon dioxide p , the calculation formula is as follows:

[0031]

[0032] Step 3-5: Calculate the adiabatic index of carbon dioxide using the following formula:

[0033]

[0034] Step 3-6: Calculate the polytropic efficiency of carbon dioxide using the following formula:

[0035]

[0036] Among them, m T K represents the polynomial index; Trepresents adiabatic index; R represents universal gas constant; T represents working fluid temperature; C represents gas flow rate; 1 and 2 represent inlet and outlet cross sections respectively;

[0037] Step 3-7: Based on the parameters given in step 1 and the inlet temperatures of each stage of the multi-stage carbon dioxide centrifugal compressor obtained in step 2, the ratio of the inlet pressure of each stage of the centrifugal compressor to the inlet static pressure of two adjacent stages is derived in combination with the polytropic index and polytropic efficiency of carbon dioxide. The calculation formula is as follows:

[0038]

[0039] Wherein, i represents the number of stages of the multi-stage carbon dioxide centrifugal compressor;

[0040] From this, we can get the inlet pressure P of each stage of the multi-stage carbon dioxide centrifugal compressor i And the pressure ratio of the two adjacent stages π i , where i=1,2,3,4...

[0041] Step 4: Given the design target parameters of the multi-stage carbon dioxide centrifugal compressor and the design parameters of the single-stage air centrifugal compressor with different flow coefficients, the design target parameters of the multi-stage carbon dioxide centrifugal compressor include the mass flow rate m CO2 , speed n CO2 The design parameters of a single-stage centrifugal compressor include mass flow rate m, speed n, shaft diameter D, inlet total temperature T t,in , total inlet pressure P t,in , gas constant R g and the adiabatic coefficient n s For a single-stage carbon dioxide compressor operating under certain conditions, the operating point of a similar single-stage air compressor can be obtained by the mass flow rate and tip speed similarity parameter Π m and Π u The mass flow rate and speed of air and carbon dioxide are similarly converted using the mass flow rate similarity parameter and the blade tip speed similarity parameter as the conversion amount. The conversion expression is as follows:

[0042] Similar conversion for mass flow rate:

[0043]

[0044]

[0045] Similar conversion of speed:

[0046]

[0047]

[0048] Among them, m CO2 and m Airis the mass flow rate of single-stage carbon dioxide and single-stage air, n co2 and n Air is the rotation speed of single-stage carbon dioxide and single-stage air, R co2 and R Air is the gas constant of carbon dioxide and air, T co2 and T Air is the inlet temperature of the single-stage carbon dioxide centrifugal compressor and the single-stage air centrifugal compressor, P i,co2 and P i,Air is the inlet pressure of the single-stage carbon dioxide centrifugal compressor and the single-stage air centrifugal compressor, D co2 and D Air is the shaft diameter of the single-stage carbon dioxide centrifugal compressor and the single-stage air centrifugal compressor, Z co2 and Z Air is the compressibility factor of carbon dioxide and air, n s,co2 and n s,Air is the adiabatic index of carbon dioxide and air, α and β are exponential parameters, and γ represents the temperature T0 relative to the reference temperature T ref The impact of

[0049] Thus, the mass flow rate m' and speed n' of air to carbon dioxide conversion with different flow coefficients are obtained;

[0050] Step 5: According to the parameters given in step 4 and the results obtained by conversion, the shaft diameter of the multi-stage carbon dioxide centrifugal compressor is determined to be 1.2D based on the uniformity of the shaft diameter, where D is the shaft diameter of the single-stage air centrifugal compressor;

[0051] Step 6: Under the condition that the error range is met, first determine the flow coefficient of the first stage, select a suitable model, and make a smooth transition connection between the first-stage outlet and the secondary-stage inlet during the series connection with the next stage; adjust the installation position and installation angle of the meridian projection of the previous stage guide vane outlet; adjust the inclination angle; combine the simulation results of the compressor and the flow field analysis, gradually deduce the appropriate models for each stage, and then recursively step by step to realize the series connection of multi-stage carbon dioxide compressors.

[0052] In step 6, the difference between the ratio of the target parameter mass flow rate m to the converted mass flow rate m" and the ratio of the target parameter speed n to the converted speed n" is used to determine whether the flow coefficient of each stage of the compressor is within the error range; based on the flow field and optimization results, a gradual series connection from single stage to multi-stage is achieved to ensure that the design of each step is within the allowable error range. Whether the flow coefficient of each stage of the compressor is within the error range is determined by the following relationship:

[0053]

[0054] Among them, m and n are the target parameters of the carbon dioxide compressor, and m" and n" are similar conversion results.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] The method includes two parts: stage matching and similarity conversion. In the stage matching part, given the relevant parameters of carbon dioxide, the matching parameters of each stage of the compressor are determined; in the similarity conversion part, based on the stage matching results, the mass flow rate and speed corresponding to a series of flow coefficients of the carbon dioxide compressor are calculated by the similarity modeling method; compared with the design requirements of the carbon dioxide compressor, the flow coefficients of each stage of the compressor are determined, and finally a multi-stage compressor is connected in series for performance calculation.

[0057] 1) Given the total temperature and pressure at the inlet and outlet of the carbon dioxide compressor, calculate the inlet temperature of each stage, calculate the compression factor, calculate the specific heat capacity at constant volume, calculate the specific heat capacity at constant pressure, calculate the polytropic index, calculate the polytropic efficiency, and calculate the pressure ratio distribution of each stage.

[0058] 2) Given the inlet temperature, inlet pressure, mass flow rate, speed and shaft diameter of the air compressor; calculate the mass flow rate and speed of the carbon dioxide compressor, and output the flow coefficients corresponding to each level of the model.

[0059] 3) Within the error range, first determine the flow coefficient of the first-stage carbon dioxide centrifugal compressor and select a suitable model. Then, when connected in series with the next-stage centrifugal compressor, perform parameterized design on the structure, and gradually optimize the models at each level by combining simulation results and flow field analysis. Through a step-by-step recursive approach, the effective series design of the carbon dioxide multi-stage centrifugal compressor is finally achieved.

[0060] The design method of the present invention is based on given carbon dioxide parameters, and calculates the mass flow rate and speed corresponding to different flow coefficients of carbon dioxide centrifugal compressors through similar modeling. By adjusting the structural parameters of the carbon dioxide centrifugal compressor, the flow coefficients of each level of carbon dioxide centrifugal compressor are determined by combining the simulation results of the carbon dioxide centrifugal compressor and the flow field analysis. By finely adjusting the internal structure of the carbon dioxide multi-stage centrifugal compressor, the energy loss in the gas flow process is reduced and the overall efficiency is improved. This method comprehensively considers multiple factors such as gas characteristics, similarity conversion criteria, inter-stage matching, adaptability to variable operating conditions, and structural reliability, ensuring the efficient and stable operation of the centrifugal compressor in different usage scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 is a flow chart of the method.

[0062] Figure 2 1 is a structural diagram of a single-stage carbon dioxide compressor according to an embodiment.

[0063] Figure 3 1 is a meridional flow diagram of a single-stage carbon dioxide compressor according to an embodiment.

[0064] Figure 4 This is a schematic diagram of similar conversion of the embodiment DETAILED DESCRIPTION

[0065] Embodiment: The design process of a four-stage carbon dioxide centrifugal compressor is as follows:

[0066] Step 1: Given the key design parameters of the four-stage carbon dioxide centrifugal compressor, including the inlet total temperature T in =308.15K, total inlet pressure P in =919000Pa, outlet total temperature T out =500K, outlet total pressure P out =6187170Pa.

[0067] Step 2: Determine the inlet temperature of each stage of the four-stage carbon dioxide centrifugal compressor based on the parameters given in step 1;

[0068]

[0069] The inlet temperatures of each stage of the four-stage carbon dioxide centrifugal compressor can be calculated as T1=308.15K, T2=362K, T3=416K, and T4=470K.

[0070] Step 3: Based on the BWRS equation, the aerodynamic thermodynamic parameters of carbon dioxide can be derived, which is an analytical model of pressure P. The specific form is as follows

[0071]

[0072] Wherein, P represents pressure, kPa; T represents temperature, K; Indicates the density of the gas, kmol / m 3 R is the universal gas constant, and the other symbols are the empirical parameters of the BWRS equation. Combined with the relevant properties of carbon dioxide, the values ​​are A0=259.3, B0=0.0404, C0=15720000, D0=457300000, E0=8850000000, a=14.352, b=0.0053, c=1615000, d=1159, α=0.0001, γ=0.0043. The solution of carbon dioxide aerodynamic thermodynamic parameters can be divided into the following steps:

[0073] Step 3-1: Calculate the density ρ of carbon dioxide at each level,

[0075] Calculated ρ1=32.39kg / m 3 ,ρ2=46.83kg / m 3 ,ρ3=61.9kg / m 3,ρ4=76.83kg / m 3 .

[0076] Step 3-2: Calculate the compression factor Z of carbon dioxide at each level:

[0077]

[0078] The calculation results show that Z1=0.958, Z2=0.9217, Z3=0.954, and Z4=0.957.

[0079] Step 3-3: Calculate the constant volume specific heat capacity c of carbon dioxide at each level v :

[0080]

[0081] Calculate c v1 =0.685, c v2 =0.736, c v3 =0.781, c v4 =0.822.

[0082] Step 3-4: Calculate the constant pressure specific heat capacity c of carbon dioxide at each level p :

[0083]

[0084] Calculate c p1 =0.915, c p2 =0.973, c p3 =1.02, c p4 =1.07.

[0085] Step 3-5: Calculate the polynomial index for each level of carbon dioxide:

[0086]

[0087] Calculate K T1 =1.3364, K T2 =1.3497, K T3 =1.3633, K T4 =1.378.

[0088] Step 3-6: Calculate the polytropic efficiency of carbon dioxide at each level:

[0089]

[0090] Calculate η p1 =0.94,η p2 =0.92, η p3 =0.9,η p4 =0.88,

[0091] Step 3-7: Combine the polytropic index and polytropic efficiency of carbon dioxide to derive the ratio of the inlet pressure of each stage of the centrifugal compressor to the inlet static pressure of the two adjacent stages:

[0092]

[0093] The inlet pressure of each stage of the four-stage carbon dioxide centrifugal compressor is P1=919000Pa, P2=1730000Pa, P3=2940000Pa, P4=4600000Pa, and the pressure ratio of the two adjacent stages is π1=1.89, π2=1.71, π3=1.58, π4=1.48. The comparison of the pressure and pressure ratio of each stage with the simulation value is shown in the following table.

[0094] Table 1 Comparison of estimation and simulation results

[0095]

[0096] Continued

[0097]

[0098] Step 4: Given the design target parameters of the four-stage carbon dioxide centrifugal compressor and the design parameters of the single-stage air centrifugal compressor with different flow coefficients, the design target parameters of the four-stage carbon dioxide centrifugal compressor include the flow rate m CO2 =181.4kg / s, speed n CO2 =8200rpm; the design parameters of a single-stage air centrifugal compressor include mass flow m, speed n, shaft diameter D, inlet total temperature T t,in , total inlet pressure P t,in , gas constant R g and the adiabatic coefficient n s ; Using the mass flow similarity parameter and the blade tip speed similarity parameter as the conversion amount, the mass flow rate and speed of air and carbon dioxide are similarly converted. The conversion results are shown in Table 2:

[0099] Table 2

[0100]

[0101] Step 5: Based on the parameters given in step 4 and the results obtained by conversion, the scaled shaft diameter of the multi-stage carbon dioxide centrifugal compressor is determined to be 1.2D=240mm based on the uniformity of the shaft diameter.

[0102] Step 6: Under the condition that the error range is met, first determine the flow coefficient of the first stage, select a suitable model, and in the process of series connection with the next stage, make a smooth transition connection between the first-stage outlet and the secondary inlet; adjust the installation position and installation angle (0 to -15) of the meridian projection of the previous stage guide vane outlet; adjust the inclination angle; combine the simulation results of the compressor and the flow field analysis, and gradually deduce the appropriate models for each stage, and then recursively deduce step by step to realize the series connection of the four-stage compressor. The flow coefficients of the four-stage carbon dioxide centrifugal compressor are finally selected as 0.15, 0.09, 0.08, and 0.04.

[0103] The design method of the present invention targets given parameters of a four-stage carbon dioxide centrifugal compressor, calculates the mass flow rate and rotation speed corresponding to compressors with different flow coefficients through similarity modeling, determines the flow coefficient of each stage of the compressor based on the proportional relationship between the calculation result and the target parameter, and reduces the energy loss in the gas flow process and improves the overall efficiency through fine adjustment of the internal structure of the multi-stage compressor.

[0104] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0105] The above contents are further detailed descriptions of the present invention in combination with specific preferred technical solutions, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as belonging to the protection scope of the present invention.

Claims

1. A similar modeling adaptation design method for a large flow compressed air energy storage compressor, characterized in that: The steps include: Step 1: Given the key design parameters of the multi-stage carbon dioxide centrifugal compressor, including the multi-stage inlet total temperature T in , multi-stage inlet total pressure P in , multi-stage outlet total temperature T out , multi-stage outlet total pressure P out ; Step 2: According to the parameters given in step 1, determine the inlet temperature of each stage of the multi-stage carbon dioxide centrifugal compressor. The inlet temperature of each stage is set as an arithmetic progression that decreases step by step. Given that the number of stages of the multi-stage carbon dioxide centrifugal compressor is k, the calculation formula for the inlet temperature of each stage is as follows: ； Among them, T i represents the inlet temperature of the i-th stage, 0<i<k+1; Therefore, the inlet temperature T of each stage of the multi-stage carbon dioxide centrifugal compressor is obtained. i ; Step 3: After the number of stages is determined, the pressure ratio of each stage is further determined according to the ratio of the inlet temperatures of each stage; therefore, according to the results calculated in step 2, the inlet pressure and pressure ratio of each stage of the multi-stage carbon dioxide centrifugal compressor are determined; based on the BWRS equation, the aerodynamic thermodynamic parameters of carbon dioxide can be derived, which is an analytical model of pressure P, and the specific form is as follows: ； Wherein, P represents pressure, kPa; T represents temperature, K; Indicates the density of the gas, kmol / m 3 ; R is the universal gas constant, symbol is the empirical parameter of BWRS equation; The solution of carbon dioxide aerodynamic thermodynamic parameters can be divided into the following sub-steps: Step 3-1: Solve for the density of carbon dioxide and rewrite the formula in step 3 as follows: ； The density is solved by the secant method, and the iterative formula is as follows: ； Initial value , ; Step 3-2: Calculate the compression factor Z of carbon dioxide using the following formula: ； Step 3-3: Calculate the constant volume specific heat capacity c of carbon dioxide v , the calculation formula is as follows: ； In the formula, Indicates molecular weight, is the density under standard conditions; Step 3-4: Calculate the constant pressure specific heat capacity c of carbon dioxide p , the calculation formula is as follows: ； Step 3-5: Calculate the adiabatic index of carbon dioxide using the following formula: ； Step 3-6: Calculate the polytropic efficiency of carbon dioxide using the following formula: ； Among them, m T K represents the polynomial index; T represents adiabatic index; R represents universal gas constant; T represents working fluid temperature; C represents gas flow rate; 1 and 2 represent inlet and outlet cross sections respectively; Step 3-7: Based on the parameters given in step 1 and the inlet temperatures of each stage of the multi-stage carbon dioxide centrifugal compressor obtained in step 2, the ratio of the inlet pressure of each stage of the centrifugal compressor to the inlet static pressure of two adjacent stages is derived in combination with the polytropic index and polytropic efficiency of carbon dioxide. The calculation formula is as follows: ； Wherein, i represents the number of stages of the multi-stage carbon dioxide centrifugal compressor; From this, we can get the inlet pressure P of each stage of the multi-stage carbon dioxide centrifugal compressor i And the pressure ratio of the two adjacent stages π i , where i=1,2,3,4... Step 4: Given the design target parameters of the multi-stage carbon dioxide centrifugal compressor and the design parameters of the single-stage air centrifugal compressor with different flow coefficients, the design target parameters of the multi-stage carbon dioxide centrifugal compressor include the mass flow rate m CO2 , speed n CO2 The design parameters of a single-stage centrifugal compressor include mass flow rate m, speed n, shaft diameter D, inlet total temperature T t,in , total inlet pressure P t,in , gas constant R g and the adiabatic coefficient n s For a single-stage carbon dioxide compressor operating under certain conditions, the operating point of a similar single-stage air compressor can be obtained by the mass flow rate and tip speed similarity parameter Π m and Π u The mass flow rate and speed of air and carbon dioxide are similarly converted using the mass flow rate similarity parameter and the blade tip speed similarity parameter as the conversion amount. The conversion expression is as follows: Similar conversion for mass flow rate: ； ； Similar conversion of speed: ； ； Among them, m CO2 and m Air is the mass flow rate of single-stage carbon dioxide and single-stage air, n co2 and n Air is the rotation speed of single-stage carbon dioxide and single-stage air, R co2 and R Air is the gas constant of carbon dioxide and air, T co2 and T Air is the inlet temperature of the single-stage carbon dioxide centrifugal compressor and the single-stage air centrifugal compressor, P i,co2 and P i,Air is the inlet pressure of the single-stage carbon dioxide centrifugal compressor and the single-stage air centrifugal compressor, D co2 and D Air is the shaft diameter of the single-stage carbon dioxide centrifugal compressor and the single-stage air centrifugal compressor, Z co2 and Z Air is the compressibility factor of carbon dioxide and air, n s,co2 and n s,Air is the adiabatic index of carbon dioxide and air, α and β are exponential parameters, and γ represents the temperature T0 relative to the reference temperature T ref The impact of Thus, the mass flow rate m' and speed n' of air to carbon dioxide conversion with different flow coefficients are obtained; Step 5: Based on the parameters given in step 4 and the results obtained by conversion, the shaft diameter of the multi-stage carbon dioxide centrifugal compressor is determined to be 1.2D based on the uniformity of the shaft diameter. Air , D Air is the shaft diameter of a single-stage air centrifugal compressor; Step 6: Under the condition that the error range is met, first determine the flow coefficient of the first stage, select a suitable model, and make a smooth transition connection between the first-stage outlet and the secondary-stage inlet during the series connection with the next stage; adjust the installation position and installation angle of the meridian projection of the previous stage guide vane outlet; adjust the inclination angle; combine the simulation results of the compressor and the flow field analysis, gradually deduce the appropriate models for each stage, and then recursively step by step to realize the series connection of multi-stage carbon dioxide compressors.

2. According to the similarity modeling adaptation design method of a large flow compressed air energy storage compressor described in claim 1, it is characterized in that: In step 6, the target parameter mass flow rate m CO2 The ratio of the converted mass flow rate m' to the target parameter speed n CO2 The difference between the ratio of the speed n' and the converted speed n' determines whether the flow coefficient of each stage of the compressor is within the error range.

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