Hydraulic conduit dynamic pressure flow characteristic calculation model and use method thereof

Abstract

The invention belongs to the field of hydraulic system hydraulic conduit dynamic characteristic theoretical modeling, and particularly relates to a hydraulic conduit dynamic pressure flow characteristic calculation model and a using method, and the hydraulic conduit dynamic pressure flow characteristic calculation model comprises a to-be-calculated section, a dynamic pressure flow characteristic calculation model and an internal variable transfer model; the section to be calculated is composed of multiple sections of conical hydraulic guide pipes, and the multiple sections of conical hydraulic guide pipes comprise guide pipes composed of a one-way progressive increase axial curve outer contour, a monotonically progressive increase axial linear outer contour, a monotonically progressive decrease axial linear outer contour and a one-way progressive decrease axial curve outer contour; each section of the conical hydraulic guide pipe comprises radial outer contours with different drift diameters and corresponds to different inlet boundary conditions and outlet boundary conditions of the conical hydraulic guide pipe. The method has the advantages of being low in calculation difficulty, high in visualization degree, high in calculation precision and easy to be compatible with hydraulic valve, pump and motor dynamic characteristic theoretical models, and efficient data interaction is achieved.

Description

Technical Field

[0001] The present application belongs to the field of theoretical modeling of dynamic characteristics of hydraulic conduits of hydraulic systems, and in particular to a calculation model for dynamic pressure and flow characteristics of hydraulic conduits and a method for using the same. Background Art

[0002] In order to meet the urgent need of airborne hydraulic systems for highly reliable hydraulic conduits, the current common method is to conduct research on hydraulic conduits throughout the body, mainly focusing on static load stress, maximum deformation displacement, fatigue strength, and modal analysis. Faced with the working conditions requiring dynamic performance of the system, the lack of an evaluation method for the dynamic performance indicators of hydraulic conduits is not conducive to an in-depth understanding and improvement of system performance. In order to facilitate the rapid evaluation of the dynamic performance of hydraulic conduits and carry out the structural optimization design of hydraulic conduits, a theoretical model that can quickly analyze the internal flow characteristics of hydraulic conduits is urgently needed.

[0003] The existing theoretical models of the internal flow characteristics of hydraulic conduits are mostly established in the frequency domain, which makes the analysis difficult, and it is difficult to analyze the dynamic characteristics of the pressure and flow inside the hydraulic conduit in the time domain. In addition, in order to adapt to the spatial layout requirements of the airborne hydraulic system pipeline and match the oil suction capacity of the hydraulic pump, hydraulic conduits with variable diameter interfaces and multiple sections of bends have begun to appear and gradually become a potential choice. Such hydraulic conduits are geometrically equivalent to hydraulic conduits with slowly varying cross-sections. Compared with straight hydraulic conduits of the same diameter, their internal pressure and flow characteristics are still unclear, which adds a lot of difficulty to the evaluation of the overall performance of the airborne hydraulic system and the optimization of the system control scheme.

[0004] Therefore, proposing a lumped parameter model to analyze the dynamic pressure and flow characteristics of such hydraulic conduits has important application significance for rapid evaluation of hydraulic conduit performance and application design. Summary of the invention

[0005] The purpose of this application is to provide a hydraulic conduit dynamic pressure flow characteristic calculation model and a method of use, so as to solve the problem in the prior art that it is difficult to effectively evaluate the overall performance of an airborne hydraulic system.

[0006] The technical solution of the present application is: a hydraulic conduit dynamic pressure flow characteristic calculation model, including a cross section to be calculated, a dynamic pressure flow characteristic calculation model and an internal variable transmission model;

[0007] The cross section to be calculated is composed of multiple sections of tapered hydraulic conduits, which include conduits respectively composed of a unidirectional increasing axial curve outer contour, a monotonically increasing axial straight line outer contour, a monotonically decreasing axial straight line outer contour, and a unidirectional decreasing axial curve outer contour; each section of the tapered hydraulic conduit includes a radial outer contour of a different diameter, and corresponds to different tapered hydraulic conduit inlet boundary conditions and outlet boundary conditions;

[0008] The dynamic pressure flow characteristic calculation model is respectively set corresponding to different tapered hydraulic conduits, forming four groups of different models, corresponding to the outer contour of the unidirectional increasing axial curve, the outer contour of the monotonically increasing axial straight line, the outer contour of the monotonically decreasing axial straight line and the outer contour of the unidirectional decreasing axial curve;

[0009] The internal variable transfer model can reflect the internal variable transfer relationship between adjacent dynamic pressure flow characteristic calculation models; there are four groups in total, corresponding to the outer contour of the unidirectional increasing axial curve, the monotonically increasing axial straight line outer contour, the monotonically decreasing axial straight line outer contour and the unidirectional decreasing axial curve outer contour.

[0010] Preferably, the four groups of dynamic pressure flow characteristic calculation models respectively include a first input boundary condition and a first output boundary condition; a second input boundary condition and a second output boundary condition; a third input boundary condition and a third output boundary condition; and a fourth input boundary condition and a fourth output boundary condition.

[0011] Preferably, the first input boundary condition includes a first inlet flow rate and a first outlet flow rate, and the first output boundary condition includes a first inlet pressure and a first outlet pressure; the second input boundary condition includes a second inlet flow rate and a second outlet flow rate, and the second output boundary condition includes a second inlet pressure and a second outlet pressure; the third input boundary condition includes a third inlet flow rate and a third outlet flow rate, and the third output boundary condition includes a third inlet pressure and a third outlet pressure; the fourth input boundary condition includes a fourth inlet flow rate and a fourth outlet flow rate, and the fourth output boundary condition includes a fourth inlet pressure and a fourth outlet pressure.

[0012] Preferably, each of the dynamic pressure-flow characteristic calculation models also includes a hydraulic conduit cross-section model and a hydraulic conduit cone model, each of the hydraulic conduit cross-section model and the hydraulic conduit cone model has corresponding input boundary conditions and output boundary conditions, each of the input boundary conditions includes an inlet pressure P1 and an outlet pressure P2, and each of the output boundary conditions includes an inlet flow Q1 and an outlet flow Q2; the inlet pressure P1, outlet pressure P2, inlet flow Q1 and outlet flow Q2 of the hydraulic conduit cross-section model and the hydraulic conduit cone model corresponding to the same dynamic pressure-flow characteristic calculation model are the same.

[0013] Preferably, the correlation formula among the inlet pressure P1, outlet pressure P2, inlet flow Q1 and outlet flow Q2 of the same dynamic pressure-flow characteristic calculation model is:

[0014] p1=C1+Z C q1 (1)

[0015] p2=C2+Z C q2 (2)

[0016] Among them, C1 and C2 are internal variables of inlet and outlet pressure flow characteristics respectively.

[0017] Preferably, the control parameters in the hydraulic conduit cone model are all determined by the viscous dissipation coefficient β f , hydraulic conduit inlet and outlet impedance size Z CA , Z CB Decide.

[0018] Preferably, the viscous dissipation coefficient β f The calculation formula is:

[0019]

[0020]

[0021]

[0022]

[0023] In the formula, R t is the pipeline liquid resistance under pipeline laminar flow state, d t is the pipe diameter, Z C is the pipeline impedance, T t is the pressure wave propagation period, l t is the pipeline length, c e is the effective propagation speed of the pressure wave.

[0024] Preferably, the dynamic pressure-flow characteristic calculation model is constructed by a plurality of linear transfer functions, and pure time lag is used to decouple pressure and flow.

[0025] Preferably, in the hydraulic conduit cone model, the inlet pressure P1 and the outlet flow Q2 are expressed as:

[0026] p1=q1Z C +q1E(s)+[p2+q2F(s)]G(s)e -T'jω (7)

[0027]

[0028] Where q1 and p2 are the input boundary conditions and output boundary conditions respectively.

[0029] Preferably, the tapered hydraulic conduit comprises a directional hydraulic conduit connected in series and a reverse hydraulic conduit connected in series, and a certain number of the directional hydraulic conduits connected in series and the reverse hydraulic conduits connected in series can form a hydraulic conduit of any cross-section.

[0030] Preferably, the internal variable transfer model includes a first input variable condition and a first output variable condition; a second input variable condition and a second output variable condition; a third input variable condition and a third output variable condition; a fourth input variable condition and a fourth output variable condition; the first input variable condition includes a first input internal variable and a first output internal variable, and the first output variable condition includes a second input internal variable and a second output internal variable; the second input variable condition includes a third input internal variable and a third output internal variable, and the second output variable condition includes a fourth input internal variable and a fourth output internal variable; the third input variable condition includes a fifth input internal variable and a fifth output internal variable, and the third output variable condition includes a sixth input internal variable and a sixth output internal variable; the fourth input variable condition includes a seventh input internal variable and a seventh output internal variable, and the fourth output variable condition includes an eighth input internal variable and an eighth output internal variable.

[0031] Preferably, there are upstream and downstream relationships within the internal variable transfer model, the downstream input internal variables are associated with the upstream output internal variables; the downstream output internal variables are associated with the upstream input internal variables; each input variable condition and output variable condition has an upstream boundary condition and a downstream boundary condition.

[0032] Preferably, the input internal variable of each upstream boundary condition is associated with the output internal variable of the downstream boundary condition, and the output internal variable of each upstream boundary condition is associated with the input internal variable of the downstream boundary condition.

[0033] Preferably, for each input variable condition: each input internal variable is associated with the output internal variable of the upstream boundary condition, and each output internal variable is associated with the input internal variable of the upstream boundary condition; for each output variable condition, each input internal variable is associated with the output internal variable of the downstream boundary condition, and each output internal variable is associated with the input internal variable of the downstream boundary condition.

[0034] Preferably, the input internal variable is a constant term.

[0035] Preferably, the output internal variable is a constant term.

[0036] The hydraulic conduit dynamic pressure flow characteristic calculation model and use method of the present application have the following advantages:

[0037] It has low computational difficulty, high visualization, high computational accuracy, and is easily compatible with theoretical models of dynamic characteristics of hydraulic valves, pumps, and motors to achieve efficient data interaction.

[0038] It is easy to realize modular design, the geometric division method of hydraulic conduits with arbitrary cross-sections is intuitive, the internal variables of the pressure and flow characteristics of conical hydraulic conduits are transmitted bidirectionally, and the relationship is clear, and the calculation accuracy of the pressure and flow characteristics of hydraulic conduits with arbitrary cross-sections is easy to ensure.

[0039] It can accurately reflect the pressure-flow transmission relationship between the inlet and outlet of a hydraulic conduit with any cross-section. It requires fewer computing resources, is highly convenient to calculate, is easy to operate, and has high adaptability to analyzing the characteristics of hydraulic systems.

[0040] It achieves compatibility with the dynamic characteristic model of the hydraulic system, efficiently reflects the internal flow characteristics of the hydraulic conduit with any cross-section, accurately calculates the dynamic flow of the hydraulic conduit with any cross-section, and facilitates the optimal design of the hydraulic conduit. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0042] Figure 1 This is a schematic diagram of the axial geometry of a hydraulic conduit with an arbitrary cross section in this application;

[0043] Figure 2 Schematic diagram of the cutaway of several conical hydraulic conduits in this application;

[0044] Figure 3 Schematic diagram of four hydraulic conduit cross-section models for this application;

[0045] Figure 4 Schematic diagram of four hydraulic conduit cone models for this application;

[0046] Figure 5 This is the relationship diagram of the internal variable transfer of the first input variable condition of this application.

[0047] 1. Section to be calculated; 2. Conical hydraulic conduit; 3. Section model of the first hydraulic conduit; 4. Section model of the second hydraulic conduit; 5. Section model of the third hydraulic conduit; 6. Section model of the fourth hydraulic conduit; 7. First internal variable transfer model; 8. Second internal variable transfer model; 9. Third internal variable transfer model; 10. Fourth internal variable transfer model; 11. Forward series hydraulic conduit; 12. Reverse series hydraulic conduit; 13. Conical model of the first hydraulic conduit; 14. Conical model of the second hydraulic conduit; 15. Conical model of the third hydraulic conduit; 16. Conical model of the fourth hydraulic conduit. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] A calculation model for the dynamic pressure and flow characteristics of a hydraulic conduit, such as Figure 1 As shown, it includes a section to be calculated 1, a dynamic pressure flow characteristic calculation model and an internal variable transfer model 10.

[0050] The section 1 to be calculated is composed of multiple sections of conical hydraulic conduits 2, which include conduits composed of unidirectional increasing axial curve outer contours, monotonically increasing axial straight line outer contours, monotonically decreasing axial straight line outer contours, and unidirectional decreasing axial curve outer contours. Each section of the conical hydraulic conduit 2 includes radial outer contours of different diameters, and corresponds to different inlet boundary conditions and outlet boundary conditions of the conical hydraulic conduit 2. Each conical hydraulic conduit 2 has a different diameter, such as Figure 1 As shown in 1.1-1.10.

[0051] The dynamic pressure flow characteristic calculation model is set corresponding to different conical hydraulic conduits 2, forming four different models, corresponding to the outer contour of the unidirectional increasing axial curve, the monotonically increasing axial straight line outer contour, the monotonically decreasing axial straight line outer contour and the unidirectional decreasing axial curve outer contour.

[0052] In order to enable each tapered hydraulic conduit 2 to form a cross-section 1 to be calculated after being connected in series, the internal variable transfer model 10 can reflect the internal variable transfer relationship between adjacent dynamic pressure flow characteristic calculation models. The internal variable transfer model 10 is formed according to the internal variable transfer relationship. There are four groups in total, corresponding to the outer contour of a unidirectionally increasing axial curve, a monotonically increasing axial straight line outer contour, a monotonically decreasing axial straight line outer contour and a unidirectionally decreasing axial curve outer contour.

[0053] Preferably, the four sets of dynamic pressure flow characteristic calculation models respectively include a first input boundary condition and a first output boundary condition; a second input boundary condition and a second output boundary condition; a third input boundary condition and a third output boundary condition; and a fourth input boundary condition and a fourth output boundary condition. Figure 3 As shown in 3.1-6.1, the output boundary conditions are as follows Figure 4 As shown in 3.2-6.2.

[0054] The first input boundary condition includes a first inlet flow rate and a first outlet flow rate, and the first output boundary condition includes a first inlet pressure and a first outlet pressure; the second input boundary condition includes a second inlet flow rate and a second outlet flow rate, and the second output boundary condition includes a second inlet pressure and a second outlet pressure; the third input boundary condition includes a third inlet flow rate and a third outlet flow rate, and the third output boundary condition includes a third inlet pressure and a third outlet pressure; the fourth input boundary condition includes a fourth inlet flow rate and a fourth outlet flow rate, and the fourth output boundary condition includes a fourth inlet pressure and a fourth outlet pressure.

[0055] Preferably, there is more than one way to connect the tapered hydraulic conduits 2 in series, such as Figure 2 As shown, it specifically includes a forward series hydraulic conduit 11 and a reverse series hydraulic conduit 12. According to the overall change law of the axial outer contour of the hydraulic conduit of any cross section, a hydraulic conduit of any cross section can be formed by a certain number of forward series hydraulic conduits 11 and reverse series hydraulic conduits 12. The specific series connection method is shown in 11.1-11.2n and 12.1-12.2n in the figure, where n represents the number of series connections.

[0056] Preferably, each dynamic pressure flow characteristic calculation model further includes a hydraulic conduit cross-section model and a hydraulic conduit cone model; the hydraulic conduit cross-section model is as follows: Figure 3 As shown, the hydraulic conduit cone model is as follows Figure 4 The four groups of hydraulic conduit section models are respectively a first hydraulic conduit section model 3, a second hydraulic conduit section model 4, a third hydraulic conduit section model 5 and a fourth hydraulic conduit section model 6. The four groups of hydraulic conduit cone models are respectively a first hydraulic conduit cone model 13, a second hydraulic conduit cone model 14, a third hydraulic conduit cone model 15 and a fourth hydraulic conduit cone model 16. Figure 4 13.1-16.1, 13.2-16.2 are the four input and output boundary conditions of the four groups of hydraulic conduit cone models.

[0057] Each hydraulic conduit section model and hydraulic conduit cone model has corresponding input boundary conditions and output boundary conditions, each input boundary condition includes an inlet pressure P1 and an outlet pressure P2, and each output boundary condition includes an inlet flow Q1 and an outlet flow Q2. The hydraulic conduit section model and hydraulic conduit cone model corresponding to the same dynamic pressure-flow characteristic calculation model have the same inlet pressure P1, outlet pressure P2, inlet flow Q1 and outlet flow Q2, and respectively reflect the cross-sectional characteristics and cone physical characteristics of the corresponding cone hydraulic conduit 2.

[0058] The hydraulic conduit cone model is a component of the hydraulic conduit cross-section model. It can be combined with the closed cavity dynamic pressure balance equation and the variable throttle dynamic flow model to reflect the influence of the change law of the geometric characteristics of the axial outer contour of the hydraulic conduit on the performance of the hydraulic system.

[0059] The correlation formula of the inlet pressure P1, outlet pressure P2, inlet flow Q1 and outlet flow Q2 of the same dynamic pressure-flow characteristic calculation model is:

[0060] p1=C1+Z C q1 (1)

[0061] p2=C2+Z C q2 (2)

[0062] Among them, C1 and C2 are internal variables of inlet and outlet pressure flow characteristics respectively.

[0063] Preferably, the control parameters in the hydraulic conduit cone model are all determined by the viscous dissipation coefficient β f , hydraulic conduit inlet and outlet impedance size Z CA , Z CB Decide.

[0064] Preferably, when calculating the internal variable transfer model, the viscous dissipation coefficient β is used f Characterizes the influence of pipeline viscous friction on the dynamic transmission characteristics of the pipeline, and its value can be obtained by the following formula:

[0065]

[0066]

[0067] In the formula, R t is the pipeline liquid resistance under pipeline laminar flow state, d t is the pipe diameter, Z C is the pipeline impedance, T t is the pressure wave propagation period, l t is the pipeline length, c e is the effective propagation speed of the pressure wave.

[0068] Preferably, the dynamic pressure-flow characteristic calculation model is constructed by multiple linear transfer functions, using pure time lag to decouple pressure and flow, and using viscous dissipation coefficient and internal fluid resistance of the hydraulic conduit to characterize viscous friction and amplitude attenuation during pressure wave propagation.

[0069] Preferably, in the hydraulic conduit cone model, the inlet pressure P1 and the outlet flow Q2 are expressed as:

[0070] p1=q1Z C +q1E(s)+[p2+q2F(s)]G(s)e-T'jω (7)

[0071]

[0072] Where q1 and p2 are the input boundary conditions and output boundary conditions respectively.

[0073] Preferably, the four groups of internal variable transfer models include a first internal variable transfer model 7 , a second internal variable transfer model 8 , a third internal variable transfer model 9 and a fourth internal variable transfer model 10 .

[0074] The first internal variable transfer model 7, the second internal variable transfer model 8, the third internal variable transfer model 9 and the fourth internal variable transfer model 10 respectively include the first input variable condition and the first output variable condition; the second input variable condition and the second output variable condition; the third input variable condition and the third output variable condition; the fourth input variable condition and the fourth output variable condition. The first input variable condition includes the first input internal variable and the first output internal variable, the first output variable condition includes the second input internal variable and the second output internal variable; the second input variable condition includes the third input internal variable and the third output internal variable, the second output variable condition includes the fourth input internal variable and the fourth output internal variable; the third input variable condition includes the fifth input internal variable and the fifth output internal variable, the third output variable condition includes the sixth input internal variable and the sixth output internal variable; the fourth input variable condition includes the seventh input internal variable and the seventh output internal variable, the fourth output variable condition includes the eighth input internal variable and the eighth output internal variable.

[0075] There are upstream and downstream relationships within the internal variable transfer model. The input internal variables of the downstream are associated with the output internal variables of the upstream; the output internal variables of the downstream are associated with the input internal variables of the upstream; each input variable condition and output variable condition has an upstream boundary condition and a downstream boundary condition; for each input variable condition: each input internal variable is associated with the output internal variable of the upstream boundary condition, and each output internal variable is associated with the input internal variable of the upstream boundary condition; for each output variable condition, each input internal variable is associated with the output internal variable of the downstream boundary condition, and each output internal variable is associated with the input internal variable of the downstream boundary condition. The association between variables is used to achieve accurate series connection of each hydraulic conduit after splitting.

[0076] And the input internal variable of each upstream boundary condition is associated with the output internal variable of the downstream boundary condition, and the output internal variable of each upstream boundary condition is associated with the input internal variable of the downstream boundary condition.

[0077] Specific as Figure 5As shown, it is an internal variable transfer model corresponding to the outer contour of the unidirectional increasing axial curve, which corresponds to the first input variable condition and the first output variable condition, wherein, for the first input variable condition, the first input internal variable 7.1.1 is associated with the output internal variable 7.3.2 of the upstream boundary condition 7.3, and the output internal variable 7.1.2 is associated with the input internal variable 7.3.1 of the upstream boundary condition 7.3; for the first output variable condition, the second input internal variable 7.2.1 is associated with the output internal variable 7.4.2 of the downstream boundary condition 7.4, the second output internal variable 7.2.2 is associated with the input internal variable 7.4.1 of the downstream boundary condition 7.4, the input internal variable 7.3.1 of the upstream boundary condition 7.3 is associated with the output internal variable 7.4.2 of the downstream boundary condition 7.4, and the output internal variable 7.3.2 of the upstream boundary condition 7.3 is associated with the input internal variable 7.4.1 of the downstream boundary condition 7.4. The internal variable transfer relationship of the internal variable transfer model for other boundary conditions is similar and will not be repeated here.

[0078] Preferably, each input internal variable and output internal variable is a constant term.

[0079] The above design has the following advantages:

[0080] It has low computational difficulty, high visualization, high computational accuracy, and is easily compatible with theoretical models of dynamic characteristics of hydraulic valves, pumps, and motors to achieve efficient data interaction.

[0081] It is easy to realize modular design, the geometric division method of hydraulic conduits with arbitrary cross-sections is intuitive, the internal variables of the pressure and flow characteristics of conical hydraulic conduits are transmitted bidirectionally, and the relationship is clear, and the calculation accuracy of the pressure and flow characteristics of hydraulic conduits with arbitrary cross-sections is easy to ensure.

[0082] It can accurately reflect the pressure-flow transmission relationship between the inlet and outlet of a hydraulic conduit with any cross-section. It requires fewer computing resources, is highly convenient to calculate, is easy to operate, and has high adaptability to analyzing the characteristics of hydraulic systems.

[0083] It achieves compatibility with the dynamic characteristic model of the hydraulic system, efficiently reflects the internal flow characteristics of the hydraulic conduit with any cross-section, accurately calculates the dynamic flow of the hydraulic conduit with any cross-section, and facilitates the optimal design of the hydraulic conduit.

[0084] Finally, it should be noted that: the drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0085] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydraulic conduit dynamic pressure flow characteristic calculation model, characterized by comprising: a section to be calculated (1), a dynamic pressure flow characteristic calculation model and an internal variable transmission model; The cross section to be calculated (1) is composed of a plurality of sections of tapered hydraulic conduits (2), wherein the plurality of sections of tapered hydraulic conduits (2) include conduits respectively composed of a unidirectionally increasing axial curve outer contour, a monotonically increasing axial straight line outer contour, a monotonically decreasing axial straight line outer contour, and a unidirectionally decreasing axial curve outer contour; each section of the tapered hydraulic conduit (2) includes a radial outer contour of a different diameter, and corresponds to different inlet boundary conditions and outlet boundary conditions of the tapered hydraulic conduit (2); The dynamic pressure flow characteristic calculation model is respectively set corresponding to different tapered hydraulic conduits (2), forming four groups of different models, corresponding to the outer contour of a unidirectional increasing axial curve, the outer contour of a monotonically increasing axial straight line, the outer contour of a monotonically decreasing axial straight line, and the outer contour of a unidirectional decreasing axial curve; The internal variable transfer model can reflect the internal variable transfer relationship between adjacent dynamic pressure flow characteristic calculation models; there are four groups in total, corresponding to the outer contour of the unidirectional increasing axial curve, the monotonically increasing axial straight line outer contour, the monotonically decreasing axial straight line outer contour and the unidirectional decreasing axial curve outer contour.

2. The hydraulic conduit dynamic pressure flow characteristic calculation model as described in claim 1, and is characterized in that: the four groups of dynamic pressure flow characteristic calculation models respectively include a first input boundary condition, a first output boundary condition; a second input boundary condition, a second output boundary condition; a third input boundary condition, a third output boundary condition; a fourth input boundary condition, a fourth output boundary condition.

3. The hydraulic conduit dynamic pressure-flow characteristic calculation model as described in claim 2, and characterized in that: the first input boundary condition includes a first inlet flow and a first outlet flow, and the first output boundary condition includes a first inlet pressure and a first outlet pressure; the second input boundary condition includes a second inlet flow and a second outlet flow, and the second output boundary condition includes a second inlet pressure and a second outlet pressure; the third input boundary condition includes a third inlet flow and a third outlet flow, and the third output boundary condition includes a third inlet pressure and a third outlet pressure; the fourth input boundary condition includes a fourth inlet flow and a fourth outlet flow, and the fourth output boundary condition includes a fourth inlet pressure and a fourth outlet pressure.

4. The hydraulic conduit dynamic pressure-flow characteristic calculation model as described in claim 2, and characterized in that: each of the dynamic pressure-flow characteristic calculation models also includes a hydraulic conduit cross-section model and a hydraulic conduit cone model, each of the hydraulic conduit cross-section model and the hydraulic conduit cone model has corresponding input boundary conditions and output boundary conditions, each of the input boundary conditions includes an inlet pressure P1 and an outlet pressure P2, and each of the output boundary conditions includes an inlet flow Q1 and an outlet flow Q2; the inlet pressure P1, outlet pressure P2, inlet flow Q1 and outlet flow Q2 of the hydraulic conduit cross-section model and the hydraulic conduit cone model corresponding to the same dynamic pressure-flow characteristic calculation model are the same.

5. The hydraulic conduit dynamic pressure flow characteristic calculation model according to claim 4, wherein the correlation equation among the inlet pressure P1, outlet pressure P2, inlet flow Q1 and outlet flow Q2 of the same dynamic pressure flow characteristic calculation model is: p1=C1+Z C q1 (1) <h2 style=";text-align:left;direction:ltr">p2 = C2 + Z<h2 style=";text-align:left;direction:ltr"> C <h2 style=";text-align:left;direction:ltr"> q2 (2) in, C1 and C2 are internal variables of inlet and outlet pressure flow characteristics respectively.

6. The hydraulic conduit dynamic pressure and flow characteristic calculation model according to claim 4, characterized in that: the control parameters in the hydraulic conduit cone model are all determined by the viscous dissipation coefficient β f , hydraulic conduit inlet and outlet impedance size Z CA , Z CB Decide.

7. The hydraulic conduit dynamic pressure flow characteristic calculation model according to claim 6, wherein the viscous dissipation coefficient β f The calculation formula is: In the formula, R t is the pipeline liquid resistance under pipeline laminar flow state, d t is the pipe diameter, Z C is the pipeline impedance, T t is the pressure wave propagation period, l t is the pipeline length, c e is the effective propagation speed of the pressure wave.

8. The hydraulic conduit dynamic pressure-flow characteristic calculation model as described in claim 4, characterized in that: the dynamic pressure-flow characteristic calculation model is constructed by multiple linear transfer functions, and uses pure time lag to decouple pressure and flow.

9. The hydraulic conduit dynamic pressure and flow characteristic calculation model according to claim 4, wherein: in the hydraulic conduit cone model, the inlet pressure P1 and the outlet flow Q2 are expressed as: p1=q1Z C +q1E(s)+[p2+q2F(s)]G(s)e -T'jω (7) Where q1 and p2 are the input boundary conditions and output boundary conditions respectively.

10. The hydraulic conduit dynamic pressure flow characteristic calculation model as described in claim 1, characterized in that: the conical hydraulic conduit (2) includes a forward series hydraulic conduit (11) and a reverse series hydraulic conduit (12), and a certain number of forward series hydraulic conduits (11) and reverse series hydraulic conduits (12) can form a hydraulic conduit of any cross-section.

11. The hydraulic conduit dynamic pressure flow characteristic calculation model according to claim 1, wherein: the internal variable transfer model comprises a first input variable condition, a first output variable condition; a second input variable condition, a second output variable condition; third input variable condition, third output variable condition; A fourth input variable condition and a fourth output variable condition; the first input variable condition includes a first input internal variable and a first output internal variable, and the first output variable condition includes a second input internal variable and a second output internal variable; the second input variable condition includes a third input internal variable and a third output internal variable, and the second output variable condition includes a fourth input internal variable and a fourth output internal variable; the third input variable condition includes a fifth input internal variable and a fifth output internal variable, and the third output variable condition includes a sixth input internal variable and a sixth output internal variable; the fourth input variable condition includes a seventh input internal variable and a seventh output internal variable, and the fourth output variable condition includes an eighth input internal variable and an eighth output internal variable.

12. A hydraulic conduit dynamic pressure flow characteristic calculation model as described in claim 11, characterized in that: there are upstream and downstream relationships within the internal variable transfer model, the downstream input internal variables are associated with the upstream output internal variables; the downstream output internal variables are associated with the upstream input internal variables; each input variable condition and output variable condition has an upstream boundary condition and a downstream boundary condition.

13. A hydraulic conduit dynamic pressure flow characteristic calculation model as described in claim 12, characterized in that: the input internal variable of each upstream boundary condition is associated with the output internal variable of the downstream boundary condition, and the output internal variable of each upstream boundary condition is associated with the input internal variable of the downstream boundary condition.

14. A hydraulic conduit dynamic pressure flow characteristic calculation model as described in claim 12, characterized in that: each input internal variable is associated with the output internal variable of the upstream boundary condition, and each output internal variable is associated with the input internal variable of the upstream boundary condition; for each output variable condition, each input internal variable is associated with the output internal variable of the downstream boundary condition, and each output internal variable is associated with the input internal variable of the downstream boundary condition.

15. The hydraulic conduit dynamic pressure and flow characteristic calculation model according to claim 12, characterized in that: the input internal variable is a constant term.

16. The hydraulic conduit dynamic pressure and flow characteristic calculation model according to claim 12, characterized in that: the output internal variable is a constant term.

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