A coaxial pump performance parameter decoupling test method

Abstract

The present application relates to a kind of test methods of decoupling of performance parameter of coaxial pump system, the coaxial pump system includes pump A and pump B, the test method includes the following steps: constructing test operating condition matrix K, the dimension of the test operating condition matrix K is n × m, n is the flow condition quantity of pump A;M is the flow condition quantity of pump B;The element of test operating condition matrix K indicates the flow condition combination of pump A and pump B;Pump A and pump B flow condition combination in test operating condition matrix K are traversed, the hydraulic test of coaxial pump system is carried out, obtains the head H A of pump A under test operating condition matrix K, the head H B of pump B, the total power P n×m Of coaxial pump system;According to the head H A Of pump A under test operating condition matrix K, calculate pump A independent head matrix H A A ;According to the head H B Of pump B under test operating condition matrix K, calculate pump B independent head matrix H B B ;The total power P n×m Of coaxial pump system is decoupled calculation, obtains pump A independent power matrix P A And pump B independent power matrix P B .

Description

Technical Field

[0001] This invention relates to the field of pump test design, specifically a test method for decoupling the performance parameters of a coaxial pump. Background Technology

[0002] A coaxial pump refers to two or more pumps that share the same drive shaft or are driven by the same drive source. Coaxial pumps are different from multistage pumps. A multistage pump uses a single shaft to drive multiple impellers or working components, with each impeller sharing a single flow rate; therefore, all impellers or working components in a multistage pump belong to the same pump. While a coaxial pump also shares the same drive shaft or drive source for its impellers or working components, the flow rates within each impeller or working component are independent; therefore, a coaxial pump is a multi-pump system.

[0003] Coaxial pumps simplify drive systems, allowing multiple pumps to be driven by a single drive source to achieve different functional requirements. Coaxial pumps are widely used in liquid rocket engine turbopumps, simplifying the drive mechanism and reducing weight and size.

[0004] However, coaxial pumps face a problem: since multiple pumps share the same drive source, their power is often coupled together. Therefore, previous experimental methods cannot directly obtain the independent power characteristics and related efficiency characteristics of a single pump. Thus, to address the power coupling problem in coaxial pumps, an experimental method needs to be designed to obtain the independent performance parameters of each pump. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art, solve the power coupling problem of coaxial pumps, and obtain independent performance parameters for each coaxial pump.

[0006] The solution of this invention is: a test method for decoupling performance parameters of a coaxial pump system, wherein the coaxial pump system includes pump A and pump B, and the method includes the following steps:

[0007] Construct a test condition matrix K, which has an n×m dimension, where n is the number of flow conditions for pump A and m is the number of flow conditions for pump B; the elements of the test condition matrix K represent the combination of flow conditions for pump A and pump B.

[0008] By traversing the flow rate combinations of pump A and pump B in the test condition matrix K, a hydraulic test is conducted on the coaxial pump system to obtain the head H of pump A under the test condition matrix K. A Pump B's head H B The total power P of the coaxial pump system n×m ;

[0009] According to the test condition matrix K, the head H of pump A is... ACalculate the independent head matrix H of pump A. A A According to the test condition matrix K, the head H of pump B is... B Calculate the independent head matrix H of pump B. B B ;

[0010] The total power P of the coaxial pump system n×m Decoupling calculation yields the independent power matrix P of pump A. A Independent power matrix P of pump B B .

[0011] Preferably, the test condition matrix K is:

[0012]

[0013] Among them, K AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The combined working conditions are i = 1, 2, 3, ..., n, j = 1, 2, 3, ..., m.

[0014] Preferably, the pump A has a head H under the test condition matrix K. A for:

[0015]

[0016] Among them, H A AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The head of pump A under the combined operating conditions, i = 1, 2, 3, ..., n, j = 1, 2, 3, ..., m;

[0017] Pump A independent head matrix H A A Represented as:

[0018] H A A =[H A A1 H A A2 ,...,H A Ai ,...,H A An ] T

[0019] H A Ai For pump A under flow condition Q AiThe head of pump A under test condition matrix K is determined by the head H of pump A. A The average value obtained by averaging the rows is:

[0020]

[0021] Preferably, the head H of pump B under the test condition matrix K is... B for:

[0022]

[0023] Among them, H B AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The head of pump B under the combined operating conditions;

[0024] Pump B independent head matrix H B B Represented as:

[0025] H B B =[H B B1 H B B2 ,...,H B Bj ,...,H B Bm ] T

[0026] H B Bj Pump B under flow condition Q Bj The head of pump B under test condition matrix K is determined by the head H of pump B. B The average of the columns is obtained as follows:

[0027]

[0028] Preferably, the total power matrix P under the test condition matrix K n×m :

[0029]

[0030] Among them, P AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj Total power under combined operating conditions;

[0031] The decoupling calculation process in step S4 is as follows:

[0032] S4.1 will convert the total power matrix P n×mReconstructed into a k×1 dimension matrix:

[0033] P k×1 =[N A1 N A2 ,...,N Ai ,...,N An ] T

[0034] Where: N Ai =[P Aib1 ,P Aib2 ,...,P Aibj ,...,P AiBm ], k = n × m;

[0035] S4.2 Constructing the power decoupling equation:

[0036] A k×(n+m) ×R (n+m)×1 =P k×1

[0037] Where matrix R is the superposition matrix of the independent power of pump A and pump B:

[0038]

[0039] P A For pump A's independent power matrix:

[0040] P A =[P A1 ,P A2 ,...,P Ai ,...,P An ] T

[0041] P B Independent power matrix for pump B:

[0042] P B =[P B1 ,P B2 ,...,P Bj ,...,P Bm ] T

[0043] Among them, A k×(n+m) The coefficient matrix is ​​of dimension k×(n+m):

[0044]

[0045] S4.3 Solve the power decoupling equation to obtain the independent power matrix P of pump A. A Independent power matrix P of pump B B .

[0046] Preferably, the solution to the power decoupling equation is:

[0047] R (n+m)×1 =A′ (n+m)×k ×P k×1

[0048] Among them, A′ (n+m)×k It is the coefficient matrix A k×(n+m) The generalized inverse matrix.

[0049] Preferably, the above-mentioned test method for decoupling the performance parameters of the coaxial pump further includes the following steps:

[0050] s5 is based on the independent head matrix H of pump A A A and independent power matrix P A Find the independent efficiency matrix η of pump A. A According to the independent head matrix H of pump B B B and independent power matrix P B Find the independent efficiency matrix η of pump B. B .

[0051] Preferably, the independent efficiency matrix η of pump A A =[η A1 ,η A2 ,...,η Ai ,...,η An ] T , i = 1, 2, 3, ..., n; η Ai for:

[0052]

[0053] Where, ρ A Let g be the density of the medium in pump A, and g be the acceleration due to gravity.

[0054] Preferably, the independent efficiency matrix η of pump B B =[η B1 ,η B2 ,...,η Bj ,...,η Bm ] T j = 1, 2, 3, ..., m, η Bj for:

[0055]

[0056] Where, ρ B Let g be the density of the medium in pump B, and g be the acceleration due to gravity.

[0057] The advantages of this invention compared to the prior art are:

[0058] (1) This invention proposes a hydraulic test condition matrix for coaxial pumps, which can cover a wider range of flow conditions compared with existing hydraulic test methods for coaxial pumps, thereby obtaining more comprehensive performance parameters of coaxial pumps.

[0059] (2) The present invention constructs a linear power decoupling equation, which has a low solution cost and can quickly solve the power coupling problem of coaxial pumps, thereby obtaining independent power parameters of coaxial pumps and then obtaining independent efficiency curves for each pump. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of a coaxial pump system according to an embodiment of the present invention. Detailed Implementation

[0061] The present invention will be further described below with reference to the embodiments.

[0062] like Figure 1 As shown, the coaxial pump system has two pumps with independent flow rates, namely pump A and pump B. The number of flow rate operating conditions for pump A is n, which are Q... A =[Q A1 Q A2 ,...,Q Ai ,...,Q An ] T The number of flow rate conditions for pump B is m, where i = 1, 2, 3, ..., n, and Q is respectively. B =[Q B1 Q B2 Q B3 ,...,Q Bj ,..,Q Bm ] T (j=1,2,3,...,m). The flow conditions of pump A and pump B are paired to form the test condition matrix K, which has an n×m dimension. Matrix K is represented as:

[0063]

[0064] Among them, K AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The combined working conditions are i = 1, 2, 3, ..., n, j = 1, 2, 3, ..., m.

[0065] The test is conducted according to the test condition matrix K, and the data that can be directly measured is: the head H of pump A under the test condition matrix K. A The head H of pump B under test condition matrix K B And the total power P of the coaxial pump system under the test condition matrix K.n×m They are represented as follows:

[0066] Under test condition matrix K, the head of pump A is H A :

[0067]

[0068] Among them, H A AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The head of pump A under the combined operating conditions, i = 1, 2, 3, ..., n, j = 1, 2, 3, ..., m;

[0069] Under test condition matrix K, pump B head H B :

[0070]

[0071] Among them, H B AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The head of pump B under the combined operating conditions;

[0072] Total power matrix P under test condition matrix K n×m :

[0073]

[0074] Among them, P AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj Total power under combined operating conditions;

[0075] Pump A independent head matrix H A A Represented as:

[0076] H A A =[H A A1 H A A2 ,...,H A Ai ,...,H A An ] T

[0077] H A Ai For pump A under flow condition Q Ai The head of pump A under test condition matrix K is determined by the head H of pump A.A The average value obtained by averaging the rows is:

[0078]

[0079] Pump B independent head matrix H B B Represented as:

[0080] H B B =[H B B1 H B B2 ,...,H B Bj ,...,H B Bm ] T

[0081] H B Bj For pump B under flow condition Q Bj The head of pump B under test condition matrix K is determined by the head H of pump B. B The average of the columns is obtained as follows:

[0082]

[0083] For the total power matrix P n×m The reconstruction is performed, with a total number of data points k = n × m. The reconstructed total power matrix P has a dimension of k × 1.

[0084] Let N Ai =[P Aib1 ,P Aib2 ,...,P Aibj ,...,P AiBm The total power matrix P is composed of N Ai Represented as:

[0085]

[0086] The total power matrix P is reconstructed into a k×1 dimension matrix:

[0087] P k×1 =[N A1 N A2 ,...,N Ai ,...,N An ] T

[0088] Matrix R is the superposition matrix of the independent power of pump A and pump B, and is the solution to be found:

[0089]

[0090] Where, P A For pump A's independent power matrix:

[0091] P A =[P A1 ,P A2 ,...,P Ai ,...,P An ] T

[0092] P B Independent power matrix for pump B:

[0093] P B =[P B1 ,P B2 ,...,P Bj ,...,P Bm ] T

[0094] Construct the power decoupling equation:

[0095] A k×(n+m) ×R (n+m)×1 =P k×1

[0096] Among them, A k×(n+m) The coefficient matrix is ​​of dimension k×(n+m):

[0097]

[0098] Matrix R can be solved using the following formula:

[0099] R (n+m)×1 =A ( ′ n+m)×k ×P k×1

[0100] Among them, A′ (n+m)×k It is the coefficient matrix A k×(n+m) The generalized inverse matrix.

[0101] Therefore, the independent power matrix P of pump A A Independent power matrix P of pump B B .

[0102] Based on the obtained independent head matrix H of pump A A A and independent power matrix P A The independent efficiency matrix η of pump A can be calculated. A =[η A1 ,η A2 ,...,η Ai ,...,η An ] T, i = 1, 2, 3, ..., n; η Ai for:

[0103]

[0104] Where, ρ A Let g be the density of the medium in pump A, and g be the acceleration due to gravity.

[0105] Based on the obtained independent head matrix H of pump B B B and independent power matrix P B The independent efficiency matrix η of pump B can be calculated. B =[η B1 ,η B2 ,...,η Bj ,...,η Bm ] T j = 1, 2, 3, ..., m, η Bj for:

[0106]

[0107] Where, ρ B Let g be the density of the medium in pump B, and g be the acceleration due to gravity.

[0108] ρ B Let g be the density of the medium in pump B, and g be the acceleration due to gravity.

[0109] Thus, the independent external characteristic parameters of pump A and pump B were obtained respectively:

[0110] Pump A: Under flow condition Q A Below, head H A A Efficiency η A Power P A

[0111] Pump B: Under flow condition Q B Below, head H B B Efficiency η B Power P B

[0112] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A test method for decoupling performance parameters of a coaxial pump system, wherein the coaxial pump system includes pump A and pump B, characterized in that... Includes the following steps: Construct a test condition matrix K, which has an n×m dimension, where n is the number of flow conditions for pump A and m is the number of flow conditions for pump B; the elements of the test condition matrix K represent the combination of flow conditions for pump A and pump B. By traversing the flow rate combinations of pump A and pump B in the test condition matrix K, a hydraulic test is conducted on the coaxial pump system to obtain the head H of pump A under the test condition matrix K. A Pump B's head H B Total power of coaxial pump system ; According to the test condition matrix K, the head H of pump A is... A Calculate the independent head matrix H of pump A. A A； According to the test condition matrix K, the head H of pump B is... B Calculate the independent head matrix H of pump B. B B ; The total power of the coaxial pump system Decoupling calculation yields the independent power matrix P of pump A. A Independent power matrix P of pump B B ; The pump A has a head H under the test condition matrix K. A for: Among them, H A AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The head of pump A under the combined operating conditions, i=1,2,3,...,n, j=1,2,3,...,m; Pump A independent head matrix H A A Represented as: For pump A under flow condition Q Ai The head of pump A under test condition matrix K is determined by the head H of pump A. A The average value obtained by averaging the rows is: The head H of pump B under the test condition matrix K B for: Among them, H B AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The head of pump B under the combined operating conditions; Pump B independent head matrix H B B Represented as: Pump B under flow condition Q Bj The head of pump B under test condition matrix K is determined by the head H of pump B. B The average of the columns is obtained as follows: Total power matrix under test condition matrix K : Among them, P AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj Total power under combined operating conditions; The decoupling calculation process in step S4 is as follows: Total power matrix Reconstructed into a k×1 dimension matrix: in: k = n × m; Construct the power decoupling equation: Where matrix R is the superposition matrix of the independent power of pump A and pump B: P A For pump A's independent power matrix: P B Independent power matrix for pump B: in, The coefficient matrix is ​​of dimension k×(n+m): Solving the power decoupling equation yields the independent power matrix P of pump A. A Independent power matrix P of pump B B .

2. The test method for decoupling performance parameters of a coaxial pump system according to claim 1, characterized in that... The test condition matrix K is: Among them, K AiBj The flow rate of pump A is Q. Ai The flow rate of pump B is Q. Bj The combined working conditions are i=1,2,3,...,n,j=1,2,3,...,m.

3. The test method for decoupling performance parameters of a coaxial pump system according to claim 1, characterized in that... The solution to the power decoupling equation is: in, It is a coefficient matrix The generalized inverse matrix.

4. The test method for decoupling performance parameters of a coaxial pump system according to claim 1, characterized in that... It also includes the following steps: Based on the independent head matrix H of pump A A A and independent power matrix P A Find the independent efficiency matrix η of pump A. A According to the independent head matrix H of pump B B B and independent power matrix P B Find the independent efficiency matrix η of pump B. B .

5. The test method for decoupling performance parameters of a coaxial pump system according to claim 4, characterized in that... The independent efficiency matrix of pump A , i=1,2,3,...,n; for: in, Let g be the density of the medium in pump A, and g be the acceleration due to gravity.

6. The test method for decoupling performance parameters of a coaxial pump system according to claim 4, characterized in that... Independent efficiency matrix of pump B j=1,2,3,...,m for: in, Let g be the density of the medium in pump B, and g be the acceleration due to gravity.

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