Abstract:

Operation safety should be paid more attention for chemical reactor systems in the presence of uncertainty and time delay to prevent environmental pollution events and human injury. The uncertainty deviation maybe unadjustable during the practical operation, such the maximum tolerable delay of chemical reactor systems under uncertainty should be figured out to guarantee the operation safety. A delay tolerability index problem (DTI) and computing framework is proposed to find the maximum tolerable delay for continuous chemical reactor systems. Firstly the continuous reactor system is linearized by Taylor series spreader formula and modeling as transform function by using Laplace transform. Secondly the dynamic response performance is tested for the system with PID control, where the control action is optimized by the nonlinear control design package (NCD). Finally the delay tolerability index problem (DTI) is figured out based on the bisection search method combing with dynamic response analysis. A continuous reactor-separator system is investigated to compute the maximum tolerable delay index when the expected uncertainty deviation is considered as unadjustable condition during the operation. The analysis results demonstrate that the proposed framework/strategy may provide a simple and effective tool for the computing and application of delay tolerability index (DTI), which is also useful for the operation safety and reliability of chemical reactor system under uncertainty.

Key words: chemical reactor, time delay, uncertainty, optimize

摘要：

化工反应器系统具体操作过程中常会受到时滞和不确定参数影响，在一些操作工况下不确定参数是不可调节的。为了保证化工系统实际操作的安全和可靠性以避免环境污染事件和人员伤害，系统所能耐受的最大时滞值非常有必要得到求解和分析。提出了含不确定参数的化工反应器系统的时滞耐受度指数问题、给出了求解和应用分析框架。首先对反应器系统进行建模，采用泰勒展开式和拉普拉斯变换将反应器系统线性化成为含不确定参数及时滞的传递函数模型。其次采用PID闭环控制的控制策略对系统进行动态响应性能测试，PID参数采用MATLAB的NCD（nonlinear control design package）模块进行优化。最后采用二分法结合系统的动态响应性能测试结果对系统所能耐受的最大时滞值τ_max进行求解。以一个典型具有连续进出料的反应-分离系统为案例，对含不确定参数的反应器系统的时滞耐受度指数进行了求解和分析。研究结果表明，所提出的研究策略可以为含不确定参数的连续反应器系统的时滞耐受度指数的求解提供快速、简洁有效的方法和思路，从而提高化工反应器系统实际运行的安全和可靠性。

关键词: 化工反应器, 时滞, 不确定性, 优化