基于基环平差流量调节的锅炉水动力计算方法

Algorithm for boiler hydrodynamic calculation based on basic loop adjustment by flow regulation

鉴于采用经典的图解法在求解复杂结构锅炉的水动力特性时存在诸多的局限性,提出了一种通用的基于基环平差流量调节的锅炉水动力计算方法.算法建立了由"节点"和"阻力区段"组成的"有向流程图"所表示的计算模型,并依据流量守恒和阻力平衡的基本原理给出了节点的流量连续性方程和基环上的阻力闭合差平衡方程,进而分"粗调"和"细调"2个阶段,采用不同流量调节策略逐步缩小基本环路上的闭合压差来完成对方程的迭代求解.算法与锅炉的具体流程拓扑结构无关,能够适用于任意结构锅炉的水动力计算.实际应用表明,该算法具有优良的通用性,能够显著提高锅炉水动力计算的精度和效率.

Boiler hydrodynamic calculation mainly adopts graphic method,which is quiet complicated and tedious for solving complex boiler systems and sometimes difficult to obtain accurate results. For making up the insufficiencies of graphic method,a general algorithm for boiler hydrodynamic calculation based on basic loop adjustment by flow regulation was presented. First,a directed graph calculation model composed of ＂nodes＂ and ＂resistance sections＂ was established,and the flow continuity equations of nodes and resistance balance equations of basic loops were provided based on the model. Second,the successive iteration method was used for solving the equations. Considering the influence of heat and gravity,the solving procedure was divided into two stages,i.e.,rough flow regulation and refined flow regulation. Different adjustment strategy was implemented in each stage to reduce the resistance closure of each basic loop gradually until the solution was convergent. The algorithm is independent with the flow topology structure and suitable for hydrodynamic calculations of various configuration boilers. Practical applications show that the proposed algorithm has excellent generality and is easy to be programmed; moreover,both the accuracy and the speed of calculation are greatly improved.