Dulong-Petit传热规律下甲烷蒸汽重整反应器熵产率最小化  

Entropy generation rate minimization of steam methane reforming reactor with Dulong–Petit heat transfer law

作　　者：陈庆晓 夏少军[1,2,3] 王文华[1,2,3] 陈林根[1,2,3] CHEN Qing-xiao;XIA Shao-jun;WANG Wen-hua

机构地区：[1]海军工程大学热科学与动力工程研究室,湖北武汉430033 [2]海军工程大学舰船动力工程军队重点实验室,湖北武汉430033 [3]海军工程大学动力工程学院,湖北武汉430033

出　　处：《节能》2018年第3期31-40,共10页Energy Conservation

基　　金：国家自然科学基金项目(项目编号:51606218;51576207);海军工程大学自主立项科研项目(项目编号:20161504)

摘　　要：基于有限时间热力学理论,考虑管式活塞流转化管外热源与管内混合反应物间传热服从Dulong–Petit传热规律[q∝?(T)^(1.25)],对管式活塞流反应器中的甲烷蒸汽重整反应进行优化。在管外热源温度分布完全可控及氢气(H_2)产率、进口压力、进口反应混合物总摩尔流率和惰性气体氮气(N2)的摩尔流率均给定的条件下,以化学反应、粘性流动、传热过程的总熵产率最小为目标,应用非线性规划数值方法对反应器的最小熵产率以及管外温度的最优分布进行了数值求解,并与管外热源温度恒定、热源温度线性变化的两种参考反应器以及分别服从牛顿传热规律[q∝?(T)]和线性唯象传热规律[q∝?(T^(–1))]的最优反应器进行了比较。结果表明,最优反应器与2种参考反应器相比熵产率降低了58%以上;对反应器进行预加热有利于减小反应器的熵产率;对于最优反应器,中间段区域存在恒定的化学驱动力或恒定的热驱动力;传热规律对SMR反应器的热源与反应物温度最优构型及最小熵产率均有显著影响。Based on finite time thermodynamic theory,this paper optimizes the methane steam reforming reaction in a plug flow steam reactor,in which the heat transfer between the heat source and the reaction mixture is assumed to obey Dulong-Petit heat transfer law[q∝Δ(T)1.25].The minimum total entropy generation rate and the optimal temperature profile are obtained by using nonlinear programming numerical analysis approach with the condition that the heat source temperature is controllable and all the production of hydrogen,the inlet pressure,the total inlet molar flow rate and the molar rate of N2 are fixed.The obtained optimization results are compared with those of the reference reactors with the heat transfer strategies of constant and linear reservoir temperature operations and those for the minimum entropy generation rate of the case with Newtonian[q∝Δ(T)]and linear phenomenological[q∝Δ(T-1)]heat transfer laws.The optimal reactor can reduce the entropy generation rate by more than 58%compared to the two reference reactors;the preheating of the reactor can reduce the entropy generation rate;for the optimal reactor,there is constant chemical thermal driving force in the middle zone;the optimal temperature configurations of both the heat source and the reaction mixture for the minimum entropy generation rate are influenced by heat transfer law significantly.

关 键 词：甲烷蒸汽重整 管式反应器 熵产率最小化 有限时间热力学 

分 类 号：TK91[动力工程及工程热物理]