CN105677969B - Complex fluid network stabilization modeling method towards single machine real-time simulation - Google Patents

Complex fluid network stabilization modeling method towards single machine real-time simulation Download PDF

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CN105677969B
CN105677969B CN201610007357.1A CN201610007357A CN105677969B CN 105677969 B CN105677969 B CN 105677969B CN 201610007357 A CN201610007357 A CN 201610007357A CN 105677969 B CN105677969 B CN 105677969B
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fluid network
complex fluid
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momentum
model
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CN105677969A (en
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李国相
庞丽萍
郭琪
刘栋
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Beihang University
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Abstract

The fluid network Stability Modeling method towards single machine real-time emulation system that the present invention provides a kind of.It is characterised by comprising: establishing the element momentum model of complex fluid network；Establish complex fluid network momentum model；Analyze the characteristic of complex fluid network momentum model；According to the system stability condition of explicit fixed step size Euler method；Determine that ADAPTIVE ROBUST operator guarantees the stability of complex fluid network model.

Description

Complex fluid network stabilization modeling method towards single machine real-time simulation
Technical field
The present invention relates to the method for complex fluid network real-time emulation system Stability Modeling, belong to using explicit Euler method Solve the real-time simulation field of complex fluid network material stream process.
Background technique
Thermal-hydraulic network model is used to describe the thermal coupling relationship between heat power equipment, close with the topological structure of pipe network Correlation provides the boundary condition of the calculating such as pressure, flow, temperature for device model.Fluid network is generally by pipeline, valve, wind The basic equipments such as machine, pump composition, completes the exchange of matter and energy during Working fluid flow.Fluid network is widely used, packet Include the environmental control system, Power Plant Thermal System, gas conveying system etc. of aircraft.Establish it is general, can be suitably used for complexity The fluid network modeling method of topological structure has important practical application of significance.
Real-time Simulation Technology is on the basis of considering real-time emulation algorithm, analogue system timing, time synchronization, to reality The dynamic simulation that system carries out.Compared with simple Computer simulation, the sharpest edges of real-time simulation are virtual emulation system System can directly act on actual hardware premised on physical time is synchronous, without carrying out model foundation, mould to complex hardware in advance The complex processes such as type verification, can carry out big system simulation experiments.The son of " actual situation combination " can be realized using Real-time Simulation Technology System verifying and examination, are not only able to greatly shorten the system research and development period, additionally it is possible to system research and development cost be effectively reduced.
But the problem of real-time simulation, is, due to its hardware in loop characteristic, it is desirable that real-time emulation system is needed using fixation Time step solving system equation, in addition the complexity of fluid network, the preferable Implicit Method algorithm of stability is difficult in large size Expanded application in complex fluid network simulation.
Summary of the invention
The present invention proposes the Stability Modeling method that the real-time simulation of complex fluid network is solved using explicit Euler method, guarantees The stability that system equation solves when the real-time and fluid network Parameters variation of system emulation.
The modeling and simulating of actual complex fluid network often uses Implicit Method algorithm as system solution device, due to implicit Solver convergence is good, and in the adjustment of fluid network parameter, system is able to maintain preferable convergence.However, Implicit Method algorithm By carrying out the process of successive ignition solving system equation to each integration step, cause Implicit Method device solution efficiency poor, it is difficult to Guarantee the real-time of fluid network real-time simulation.For the real-time demand of complex fluid network real-time simulation, propose using aobvious Formula Euler method establishes complex fluid network system model as system solution algorithm.However, being when fluid network Parameters variation System model is easy to produce rigidity and causes to solve and is difficult to restrain, and for system instability, the invention proposes adaptive Shandongs Stick operator can guarantee system stability while guaranteeing system solution real-time when system parameter arbitrarily changes, thus It is proposed the complex fluid network stabilization modeling method towards real-time simulation.
According to an aspect of the invention, there is provided a kind of complex fluid network stabilization towards single machine real-time simulation is built Mould method, characterized by comprising:
Establish the element momentum model of complex fluid network；
Establish complex fluid network momentum model；
Analyze the characteristic of complex fluid network momentum model；
It is proposed the system stability condition of explicit fixed step size Euler method；
Complex fluid network stabilization ADAPTIVE ROBUST operator is established, system is imitative when ensureing the variation of complex fluid network parameter Genuine stability.
Figure of description
Fig. 1 is to be suitable for the invention temperature and humidity control system ventilation fluid network model schematic diagram.
Fig. 2 shows explicit Euler method convergence domain.
The variation of system features value when Fig. 3 shows valve opening adjustment.
The variation of system condition number when Fig. 4 shows valve opening adjustment.
Fig. 5 shows flow system flow response curve when valve opening is adjusted to 8%.
Fig. 6 shows improved system features value variation when valve opening adjustment.
Fig. 7 shows that valve opening is adjusted to improved flow system flow response curve when 8%.
Fig. 8 shows complex fluid network real-time simulation Stability Modeling method according to an embodiment of the invention Flow chart.
Specific embodiment
According to the present invention, complex fluid network is emulated using explicit Euler method, by taking temperature and humidity control system as an example, Its ventilation fluid network modulus principle figure is as shown in Figure 1, wherein ventilation fluid network uses active draft type, by cabin (101) Internal Hot wet air heating is delivered to condensing heat exchanger (105) through draft fan (103), cooling hydrofuge is carried out, to reach control The purpose of cabin temperature and humidity.
The convergence domain of explicit Euler method is with (- 1,0) in complex plane Left half-plane for the center of circle as shown in Fig. 2 dash area Unit circle in.Ventilation fluid network is emulated, when fluid network system parameter (valve opening) adjustment, will lead to and be Eigenmatrix characteristic value of uniting and its conditional number corresponding change, as shown in Figure 3 and Figure 4, when parameter is adjusted to certain value, system is asked Solution does not restrain, as shown in Figure 5.Therefore, the present invention proposes ADAPTIVE ROBUST operator, and no matter how system parameter adjusts, and system is special Value indicative controls in explicit Euler method absolute convergence domain, as shown in fig. 6, system emulation result is as shown in Figure 7.According to invention The flow chart of the complex fluid network real-time simulation Stability Modeling method of one embodiment is as shown in Figure 8.
A kind of temperature and humidity control system ventilation fluid network is suitable for the invention as shown in Figure 1, according to element momentum, matter It measures conservation equation (step 202) in Fig. 8), binding member connection relationship establishes ventilation fluid network pressure flow equation of momentum group (1) formula (step 203) in Fig. 8:
Wherein, Pi, i=1,2 ..., 5 indicate the outlet pressure of i-th of element, Pa；Ri, i=1,2 ..., 6 indicate i-th The frictional resistance of element, Pa s2/kg2；
When valve opening changes, it will lead to flow resistance when corresponding fluid flows through valve and corresponding change occur, Being easy to make above-mentioned equation group to generate Ill-posed characteristic, (step 204) in Fig. 8, Fig. 4 show system condition number to be changed with valve opening Situation.Therefore, in order to guarantee the accuracy of system solution, corresponding Autonomous Ordinary Differential Equations need to be constructed and (walked in Fig. 8 It is rapid 205):
Obviously, the solution of equation group (1) is unique singular point of autonomous system (2).Solve the feature of ordinary differential autonomous system (2) Matrix:
Wherein m=sign (w5)+|wdrain/w5| and | wdrain/w5|<<1。
The time-varying characteristics of valve opening make entire fluid network system Electro-hydraulic Proportional System, the variation of system features matrix Can correspond to makes system features value change.It is respectively corresponding different valve opening system features values and system shown in Fig. 3 and Fig. 4 Conditional number situation of change.When valve opening is greater than 30%, system features value and rigidity are than substantially constant, and system meets aobvious at this time Formula Euler method it is exhausted to the condition of convergence (| 1+h λ | < 1)；Valve opening adjustment continues to turn down, and the one of characteristic value of system is rapid Become smaller, system rigidity ratio increased dramatically, and when aperture is less than 10% or so, the one of characteristic value h λ of system1< -2, no longer Meet explicit Euler method absolute convergence condition.Correspondence system Traffic simulation result is as shown in figure 5, when system is run to 10s When valve opening is gradually adjusted to 8%, system emulation result does not restrain, and vibrates.
For this purpose, present inventors have proposed ADAPTIVE ROBUST operatorsTo reduce sytem matrix conditional number, guarantee system parameter The convergence of system when adjustment:
Wherein, subscript i indicates corresponding i-th of fluid network element,Indicate the adaptive of i-th of fluid network element Robust operator；H indicates that Euler method solves time step, s；M indicates the flow loss coefficient of counter element equation, m=sign (w) +|wdrain/w|。
Through the improved differential equation of ADAPTIVE ROBUST operator (step 206) is as shown in formula (5) in Fig. 8:
Corresponding improved sytem matrix are as follows:
Definition: A=(a is setij) it is that n × n ties up complex matrix, it enablesG is enabled againi=z ∈ C | | z- aii|<δi, (i=1,2 ..., n), i.e. GiFor on complex plane C with aiiFor center of circle δiFor the closed disk of radius, referred to as matrix A There are n Gai Eryuan for Gai Eryuan, n rank matrix A.
Theorem: if A=(aij) it is that n × n ties up complex matrix, your circle of the n lid of A is G1,G2,…,Gn, then:
(1) all eigenvalue λs of A are all in your disk of this n lid, i.e.,
(2) if there is k unions to form a connected region in n of A lid your disk, and with remaining n-k disk It is all non-intersecting, then just there is the k characteristic value of A, particularly, have in isolated your disk of lid and only one is special in this connected region Value indicative.
According to Gerschgorin theorem it is found that improve after system characteristic value h λJ’It is distributed in (- 1,0) as the center of circle, 1 is In the circle of radius, i.e., in the range as shown in Figure 2 of explicit Euler method absolute convergence domain.Real system feature Distribution value is with valve opening Variation is as shown in fig. 6, system can guarantee preferable convergence under valve any opening degree, the good (step in Fig. 8 of system stability 207)).When system valve opening is adjusted to 8%, correspondence system flow is responded as shown in fig. 7, demonstrating face proposed by the present invention To the correctness of the complex fluid network stabilization modeling method of real-time simulation.
The present invention has the advantage that compared with the conventional method
(1) it uses explicit solution algorithm and solves complex fluid network, system solution is high-efficient, real-time is good；
(2) there is ADAPTIVE ROBUST operator, improve complex fluid network system model, ensure that complex fluid network is joined The stability of system model when number variation；
(3) method of the invention is based on lid that disk theory and carries out theory analysis to complex fluid network system features value, It is theoretical in conjunction with derivation algorithm numerical stability, under the premise of guaranteeing system stability, greatly improve the real-time of system.

Claims (1)

1. the complex fluid network stabilization modeling method towards single machine real-time simulation, characterized by comprising:
Establish the element momentum model of complex fluid network；
Establish the element quality model of complex fluid network；
Establish complex fluid network momentum model；
Analyze the characteristic of complex fluid network momentum model；
Determine the system stability condition of explicit fixed step size Euler method；
Complex fluid network stabilization ADAPTIVE ROBUST operator is determined, so that system is imitative when ensureing the variation of complex fluid network parameter Genuine stability,
Wherein:
The step of establishing the element momentum model of complex fluid network includes that element momentum model is characterized are as follows:
Pin-Pout=Rw | w | (1)
In formula:
PinIndicate pressure at element inlet, unit Pa；
PoutIndicate pressure at component outlet, unit Pa；
R indicates the frictional resistance of element, and unit is Pa s2/kg2；
W expression flows through the mass flow of the working medium of element, and unit kg/s, w are that positive value indicates that working medium is flowed to out by element inlet Mouthful, indicate that working medium flows to entrance by component outlet for negative value,
The step of establishing the element quality model of complex fluid network includes that element quality model is characterized are as follows:
W=wn (2)
In formula:
wnIndicate flow through adjacent downstream element working medium mass flow, unit kg/s,
Described the step of establishing complex fluid network momentum model includes complex fluid network momentum model complex fluid net Network pressure flow equation group (3) characterization are as follows:
In formula:
Subscript 0~6 respectively indicates the element in complex fluid network, respectively cabin, pipeline, blower, pipeline, condensing heat-exchange Device, valve, pipeline,
P indicates component outlet pressure, unit Pa；
The mapped function relation of f expression pressure；
W indicates to flow through the working medium mass flow of element, unit kg/s；
R indicates the frictional resistance of element, and unit is Pa s2/kg2；
ΔP0For blower press, unit Pa；
wdrainFor condensate quality flow, unit kg/s,
The step of characteristic of the analysis complex fluid network momentum model includes the equation of momentum group for analyzing complex fluid network Eigenmatrix, the complex fluid network equation of momentum group eigenmatrix are as follows:
Wherein:
J indicates complex fluid network equation of momentum group eigenmatrix；
Characterize the condition number calculating method of complex fluid network characterization matrix condition are as follows:
Wherein:
The conditional number of cond (J) expression eigenmatrix J；
|λ(J)|maxIndicate the maximum characteristic value of modulus value of eigenmatrix J；
|λ(J)|minIndicate the smallest characteristic value of modulus value of eigenmatrix J,
The step of determining the system stability condition of explicit fixed step size Euler method includes the stability explicit fixed step size Euler method Condition determines are as follows:
|1+hλ|<1 (7)
Wherein:
H expression Euler method solution time step, unit s,
λ indicates system arbitrary characteristics value,
The step of determining complex fluid network stabilization ADAPTIVE ROBUST operator include complex fluid network stabilization oneself Robust operator is adapted to determine are as follows:
Wherein:
Subscript i indicates corresponding i-th of fluid network element,
Indicate the ADAPTIVE ROBUST operator of i-th of fluid network element；
The flow loss coefficient of m expression counter element equation, m=sign (w)+| wdrain/ w |, wdrainFor condensate quality flow.
CN201610007357.1A 2016-01-06 2016-01-06 Complex fluid network stabilization modeling method towards single machine real-time simulation Expired - Fee Related CN105677969B (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101322100A (en) * 2005-10-03 2008-12-10 中央洒水装置公司 System and method for evaluation of fluid flow in a piping system
CN104036062A (en) * 2013-03-05 2014-09-10 利弗莫尔软件技术公司 Numerical Simulation Of Fsi Using The Space-time Ce/se Solver With Moving Mesh For The Fluid Domain

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KR101267627B1 (en) * 2011-06-13 2013-05-27 한국과학기술원 SPH Fluid simulation method and system for Multi-Level Vorticity, recording medium for the same

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101322100A (en) * 2005-10-03 2008-12-10 中央洒水装置公司 System and method for evaluation of fluid flow in a piping system
CN104036062A (en) * 2013-03-05 2014-09-10 利弗莫尔软件技术公司 Numerical Simulation Of Fsi Using The Space-time Ce/se Solver With Moving Mesh For The Fluid Domain

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
流体网络仿真模块化建模方法研究;耿江华等;《船舶科学技术》;20150831;第37卷(第8期);第128-131页

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