Due to the complexity of the multiphase flow process and the limitation of traditional single sensor, the existing measurement methods can not meet the requirement of accurate measurement for industrial processes. In ...
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Due to the complexity of the multiphase flow process and the limitation of traditional single sensor, the existing measurement methods can not meet the requirement of accurate measurement for industrial processes. In order to solve the problem of accurate and comprehensive information acquisition of the multiphase flow process, a multi-sensor fusion method is proposed for multiphase flow parameter measurement. A conductance-ring sensor and a cone-shape differential pressure sensor are selected as the means of measurement. The cross-correlation velocity measurement technology is combined with the measurement model of differential pressures. Kalman centralized fusion estimation method not only can realize the effective information fusion between heterogeneous sensors, but also can satisfy accurate and real-time requirements of the multiphase flow parameters estimation. The experiment results have verified the feasibility of the method.
Two-phase flow is a frequently encountered and widely existed flow phenomenon in industrial processes. Accurate measurement on its process parameters has always remained a challenge for both the academic and engineeri...
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Two-phase flow is a frequently encountered and widely existed flow phenomenon in industrial processes. Accurate measurement on its process parameters has always remained a challenge for both the academic and engineering world. An inner-out conductance ring sensor is proposed to measure the dispersion phase fraction in an annular flow channel. The sensing field distribution along with the sensitivity distribution has been numerically studied through simulations, two typical phase distributions of stratified flow and bubbly flow are simulated for phase concentration measurement analysis of the inner-out conductance ring sensor. A prototype of this sensor is fabricated and tested in static experiments. The experiment results demonstrate that the proposed conductance sensor outputs a voltage directly proportional to the phase fraction within the target annular channel. The deviation of experiment measurement to numerical work is analyzed.
In this paper, the problem of finite-time control for a class of uncertain Markovian jump systems subject to disturbance and input constraint is investigated. The system to be considered is more general where only par...
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In this paper, the problem of finite-time control for a class of uncertain Markovian jump systems subject to disturbance and input constraint is investigated. The system to be considered is more general where only partial information of transition probabilities is known. In practical systems, the amplitude that can be made to the manipulated variables is always limited. Therefore, a control algorithm should be considered in this situation. A sufficient condition is established to ensure that the state trajectory remains in a bounded region of the state space in mean square sense over a fixed time interval. Based on it, the corresponding finite-time stochastic stabilization criterion is proposed by considering the input constraint simultaneously. Numerical examples are given to show the validity of the proposed methods.
In nature world and engineering production and living, multi-phase flow plays a very important role. The research of multi-phase flow in the pipe condition is necessary and the experiment device of it is very helpful....
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In nature world and engineering production and living, multi-phase flow plays a very important role. The research of multi-phase flow in the pipe condition is necessary and the experiment device of it is very helpful. For this reason, a PC-Based small-scale physical experimental system is build by Tianjin Key Laboratory of process Measurement and control. Its control system combines configuration software and Visual Basic software, the executive system is made up of several electric control valves, and the sensors consist of pressure sensors, temperature sensors, flow rate sensors, ultrasonic liquid level sensors, and so on. There are a variety of signals like digital signals, pulse signals, current analog signals, voltage analog signals, etc. And by this experimental device, the typical flow pattern can be formed, and the basic requirements of multi-phase flow research can be met. Some built-in problems and more new function have been added. These improvements of the system make it be more convenient according to the increasing demand of the multi-phase experiments.
The requirement of gas flow facility with high pressure is increasing. But, the experiences of development the closedloop high pressure facility are not enough. Critical flow sonic Nozzles gas flow facility with mediu...
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The aim of this work is to present an entropy-like Lyapunov function based dynamic feedback design technique for quasi-polynomial and Lotka-Volterra systems. It is shown, that the dynamic feedback design problem is eq...
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The aim of this work is to present an entropy-like Lyapunov function based dynamic feedback design technique for quasi-polynomial and Lotka-Volterra systems. It is shown, that the dynamic feedback design problem is equivalent to the feasibility of a bilinear matrix inequality. The problem is also formulated as a control Lyapunov function based feedback design when the Lyapunov function parameters are given, the solution of this problem can be obtained by solving a linear matrix inequality. The developed method is illustrated on a simple numerical example.
The exponential stabilization problem of a class of linear systems with actuator saturation is addressed in this paper. In an approach different from the previous results where the continuous controllers are used all ...
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ISBN:
(纸本)9781467355339
The exponential stabilization problem of a class of linear systems with actuator saturation is addressed in this paper. In an approach different from the previous results where the continuous controllers are used all the time, here the periodically intermittent control is proposed to ensure the exponential stability of the closed-loop systems. An exponential stability criterion is suggested using the contractive invariant ellipsoid as an estimate of the domain of attraction. In addition, the exponential convergence rate is explicitly given. The feedback controller can also be designed by regarding the feedback gain as an additional variable. A numerical example is presented to illustrate the effectiveness of our theoretical analysis.
This paper focuses on the admissibility condition for fractional-order singular system with order α∈(0, 1). The definitions of regularity, impulse-free and admissibility are given first, then a sufcient and necessar...
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This paper focuses on the admissibility condition for fractional-order singular system with order α∈(0, 1). The definitions of regularity, impulse-free and admissibility are given first, then a sufcient and necessary condition of admissibility for fractional-order singular system is established. A numerical example is included to illustrate the proposed condition.
A novel adaptive data driven control strategy is proposed for general discrete nonlinear systems. The controller is designed based on the Simultaneous Perturbation Stochastic Approximation (SPSA) method, and is constr...
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A novel adaptive data driven control strategy is proposed for general discrete nonlinear systems. The controller is designed based on the Simultaneous Perturbation Stochastic Approximation (SPSA) method, and is constructed through use of a Function Approximator (FA), which is fixed as a neural network here. In this novel approach, the parametric estimation is designed to be adaptive, which greatly improves the control ability. The proposed control strategy is finally applied to solve nonlinear tracking problems for discrete-time nonlinear systems. The feasibility and effectiveness of the proposed adaptive data driven control strategy is well demonstrated through Simulation comparison tests.
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