Simulink在全混流反应器中的应用

尝试一种进行化工过程仿真的新方法，利用Matlab的仿真工具箱Sireulink，对全混流反应器进行可视化建模和仿真计算，以一个一级不可逆放热反应为例，进行稳态模拟及动态模拟，根据模拟结果提出反应器最优操作状态，并对动态模拟的各稳态操作点进行详细分析，同时提出了避免不稳定性的方法。结果表明，使用Simulink所建立的模型，具有很好的开放性和可移植性，还能轻松地分析过程动态特性，是进行建模仿真的好工具。     

计算机在多级串联全混流反应器中的应用

在多级串联全混流反应器中进行二级反应时,第N级反应器的出口浓度表达式中含有N个套起来的根号。运用递推关系式可求其值。但解析法求解费时费力,图解法又不够精确。本文克服了上述两种方法的不足,开发了一种新的方法,利用C 语言依据递推关系式编制程序,该程序能够迅速求解,而且程序运行结果与计算结果完全一致。该方法简便、快速、精确,在多级串联全混流反应器的设计中具有重要的应用价值。     

计算机在全混流反应器多级串联的应用

在全混流反应器多级串联作3/2级化学反应时,为了求各级反应器的出口浓度,就具体实例利用图解法、递推法和计算机程序法求解。结果表明：递推法计算结果和程序运行结果一致,但递推法费时费力,图解法又不够精确。只有计算机程序的方法简便、快速、精确,在全混流反应器多级串联的设计中具有重要的应用价值。而且,对实际化工生产过程的控制也具有重要意义。     

三种方法求全混流反应器多级串联的出口浓度

求出口浓度在全混流反应器多级串联的设计中具有重要的应用价值,对分析出口物料的组成也具有重要意义。目前常用的图解法和递推法精度低、速度慢。本文旨在研究一种精确、快速、通用的计算方法。通过计算机编程求解,并与传统方法比较,分析新方法在精度和速度上的优势。分析结果表明计算机程序法具有精确、快速、通用、方便的优点,可以显著提高计算效率,具有推广价值。     

基于LabVIEW的信号分析与仿真

信号分析作为数字信号处理的主要组成部分,在各个领域得到了广泛的应用.本文对信号的时域分析、频域分析以及联合时频分析方法进行了研究,设计了数据信号分析的软件体系结构,并采用LabVIEW工具以图形界面的方式实现了周期信号的分析与仿真.仿真结果表明基于LabVIEW的信号分析系统可以准确、高效地对信号进行多功能的分析,具有很好的应用前景.     

求多级串联全混流反应器的出口浓度——2/3级不可逆反应

在多级串联全混流反应器中进行2,3级不可逆化学反应时,求每一段反应器的出口浓度,在多级串联全混流反应器的设计中不仅具有重要应用价值,而且在实际的化学工业生产中也具有重要意义,经济效益显著。前文研究表明:可用作图法和代数法求解,但作图法不够精确,代数法求解又较为繁琐,且当反应器个数很多时,上述2种方法则无能为力。而计算机程序法能克服以上2种方法的不足。本文结合具体实例,依据第N段反应器的出口浓度的表达式,利用C*语言编制程序。通过该程序能讯速的求解。该法具有简便、精确、高效以及通用的优点,可以显著的提高计算效率,具有推广价值。     

光气合成反应器动态仿真

该文对光气合成管式反应器的动态仿真技术进行了研究.根据物料及焓守恒方程建立了管式反应器的动态机理模型,并根据模型的形式和特点选择了适当的数值计算方法,开发了光气反应器的动态模拟程序模块.模块应用结果表明,达到稳态时的结果能比较真实地反映生产实际情况,动态过程能很好地反映生产的变化趋势,并能完成对非正常工况的模拟.该模型对光气合成反应器动态特性和控制方式的研究以及光气合成相关工艺仿真培训系统软件的开发等都有重要的意义.     

基于LabVIEW呼吸机时间切换通气模式的建模仿真

呼吸机是医用必备工具,在临床应用中越来越普遍.虚拟技术能够为医生制定医疗方案提供一定的帮助.采用LabVIEW软件虚拟呼吸机前面板,并对呼吸机气流源、气管、肺等部分进行,建模.采用计算机动态模拟时间切换机械通气中物理过程,建立理论曲线快速演示和快速分析平台,探讨其它原理机械通气计算机仿真的可行性.     

混流生产线的Flexsim仿真应用研究

由于产品市场的变化,目前越来越多的工厂选择多品种,小批量的生产模式,混流生产线也被企业广泛采用.本文着重论述了混流生产线的投产排序问题,提出了影响其排序优劣的三种因素,并对每种因素对总加工时间的影响运用Flexsim仿真软件进行了研究,找出了寻求较优投产排序的方法.     

LabVIEW在蒸汽发生器动态仿真研究的应用

由于蒸汽发生器是压水堆的核心部件,而且蒸汽发生器的故障概率也比较高,因此蒸汽发生器的仿真研究是现今核电厂控制领域的重要课题之一。本文重点介绍一种新型仿真语言LabVIEW在蒸汽发生器仿真中的应用,对比以前所用到的仿真语言,这种语言带来许多的便利与强大的功能。     

Design of observer based nonlinear model predictive controller for a continuous stirred tank reactor

Model predictive control (MPC) schemes are now widely used in process industries for the control of key unit operations. Linear model predictive control (LMPC) schemes which make use of linear dynamic model for prediction, limit their applicability to a narrow range of operation (or) to systems which exhibit mildly nonlinear dynamics.

In this paper, a nonlinear observer based model predictive controller (NMPC) for nonlinear system has been proposed. An approach to design NMPC based on fuzzy Kalman filter (FKF) and augmented state fuzzy Kalman filter (ASFKF) has been presented. The efficacy of the proposed NMPC schemes have been demonstrated by conducting simulation studies on the continuous stirred tank reactor (CSTR). The analysis of the extensive dynamic simulation studies revealed that, the NMPC schemes formulated produces satisfactory performance for both servo and regulatory problems. Simulation results also include an inferential control case, where the reactor concentration is not measured but estimated from temperature measurement and used in the NMPC based on FKF and ASFKF formulations.     

Control of a non-isothermal continuous stirred tank reactor by a feedback-feedforward structure using type-2 fuzzy logic controllers

A control system that uses type-2 fuzzy logic controllers (FLC) is proposed for the control of a non-isothermal continuous stirred tank reactor (CSTR), where a first order irreversible reaction occurs and that is characterized by the presence of bifurcations. Bifurcations due to parameter variations can bring the reactor to instability or create new working conditions which although stable are unacceptable. An extensive analysis of the uncontrolled CSTR dynamics was carried out and used for the choice of the control configuration and the development of controllers. In addition to a feedback controller, the introduction of a feedforward control loop was required to maintain effective control in the presence of disturbances. Simulation results confirmed the effectiveness and the robustness of the type-2 FLC which outperforms its type-1 counterpart particularly when system uncertainties are present.     

Adaptive neural network control for a class of continuous stirred tank reactor systems

In this paper, the control problem of continuous stirred tank reactors （CSTR） is studied. The considered CSTR are required to contain unknown functions and unknown dead zone input. An adaptive controller that uses the neural networks （NNs） is provided to solve the unknown terms. The proposed approach overcomes the effect of the dead zone input. The dead zone input in the systems is compensated for by introducing a new Lyapunov form and Young＇s inequality. The backstepping procedure is exploited to implement controller design with adaptation laws. The stability is analyzed using Lyapunov method. The performance is examined for CSTR to confirm the effectiveness of the proposed approach based on computer simulation.     

A robust control scheme for nonlinear non-isothermal uncertain jacketed continuous stirred tank reactor

A Non-isothermal Jacketed Continuous Stirred Tank Reactor (CSTR) is extensively used in chemical as well as in other process industries to manufacture different products. The dynamics of non-isothermal CSTR are highly nonlinear and open-loop unstable in nature. Moreover, it may have parametric uncertainties, disturbances and un-modeled side reactions which may cause the reactor temperature to deviate from the reference value. This deviation may degrade quality of the product because the chemical reaction inside the CSTR depends on reactor temperature. For such a nonlinear, unstable and uncertain process, designing a control scheme with the ability to reject the effects of disturbances along with a good reference tracking capability is a challenging control engineering problem. In this work, a novel robust sliding mode control technique named as Improved Integral Sliding Mode Control (IISMC) has been presented for uncertain non-isothermal jacketed CSTR process. Moreover, a variety of recently developed sliding mode control techniques such as Classical Integral Sliding Mode Control (CISMC) and Super Twisted Algorithm based Sliding Mode Control (STA-SMC) have also been devised and compared with the proposed approach in order to investigate the effectiveness of the proposed scheme. A Lyapunov based analysis has also been provided to assure the robust stability of the closed loop process. Furthermore, in order to extend the state feedback approach to the output feedback scheme, two robust observers; High Gain Observer (HGO) and Extended High Gain Observer (EHGO), are also designed for the very process. They have also been compared with each other and have been investigated for robust stability using Lyapunov based approach. Finally, an output feedback control scheme using IISMC and EHGO has been presented and its performance has been examined and compared with the IISMC based state feedback approach. The simulation results show that the proposed control scheme effectively rejects the uncertainties and disturbances without leading the process to instability and offers good reference tracking capabilities.     

基于Takagi-Sugeno模糊双线性模型的连续搅拌反应釜H∞控制

本文研究了一类连续搅拌反应釜(CSTR)系统的H1控制问题. 系统中的非线性动态特性可采用Takagi-Sugeno(T-S)模糊双线性模型进行描述. 通过引入两个自由矩阵, 给出一个新的保证闭环模糊双线性系统在H1性能指标下全局渐近稳定的充分条件和控制器设计方法, 并且该条件最终可归结为求解一组线性矩阵不等式的可行性问题. CSTR系统的仿真结果表明设计方法的有效性.     

Stability analysis of non-interacting control of continuous stirred tank reactor†

A continuous stirred tank reactor operating around a stable equilibrium point and having interaction may become unstable when made noii-intcractivo by tho addition of compensators. Procedures for selecting the settings of tho feedback controllers to obtain any desired degree of stability in the non-interacting system are worked out in this paper. A numerical example of a continuous stirred tank reactor with an irreversible, exothermic first-order reaction is taken and controller settings for its stable non-interacting operation worked out.     

A continuous stirred tank heater simulation model with applications

This article presents a first principles simulation of a continuous stirred tank heater pilot plant at the University of Alberta. The model has heat and volumetric balances, and a very realistic feature is that instrument, actuator and process non-linearities have been carefully measured, for instance to take account of the volume occupied by heating coils in the tank. Experimental data from step testing and recordings of real disturbances are presented. The model in Simulink and the experimental data are available electronically, and some suggestions are given for their application in education, system identification, fault detection and diagnosis.     

Immersion and invariance adaptive control of a class of continuous stirred tank reactors

An immersion and invariance(I&I) manifold based adaptive control algorithm is presented for a class of continuous stirred tank reactors(CSTR) to realize performance-oriented control in this paper. The nonlinear contraction method is combined into the control law design to render the closed-loop CSTR system globally asymptotically stable, firstly. Then, the I&I method is used to form the adaptation law such that the off-the-manifold coordinate(the parameter estimation error) converges to zero using P-monotone property enforced by selecting tuning function in manifold. As a result, the state of the closed-loop CSTR converges to its desired value asymptotically. The simulation is given to illustrate the effectiveness of the presented algorithm.     

连续搅拌反应釜的固定时间命令滤波跟踪控制

针对一类连续搅拌反应釜系统的跟踪控制问题,提出一种基于反步法和模糊逻辑系统的自适应固定时间命令滤波控制方法.利用命令滤波器引入误差补偿机制消除滤波误差的影响,并解决反步法虚拟控制信号重复求导的问题;采用模糊逻辑系统对系统中存在的非线性部分进行逼近;利用固定时间控制方法使系统跟踪误差更迅速收敛至较小邻域内,且收敛时间不依赖系统初始状态;通过Lyapunov定理证明连续搅拌反应釜系统的闭环稳定性;利用Matlab/Simulink仿真实验验证所提出控制方法的有效性.与现有控制方法相比,该控制方法具有控制器结构简单、收敛速度快、控制精度高、无超调等优点.