燃烧中几个单分子反应体系的非谐振效应理论研究

发布时间：2018-11-02 06:51

【摘要】：燃烧在日常生活中起着不可替代的作用。目前,世界上大约90%的能量都是由燃烧生成的。燃烧的应用十分广泛,几乎所有人类所需要的动力生产,都涉及到燃料的燃烧。在人类所需的动力生产中,发动机是燃料燃烧产生能量的一种重要热能动力装置。发动机内燃料燃烧的本质是化学反应。因此,对于燃料燃烧的化学反应动力学过程的研究,对提高燃烧效率、降低污染物排放以及寻找替代燃料等具有重要意义。而在发动机燃料燃烧过程中,燃料高温裂解过程是十分重要的。对于其化学反应动力学过程的研究,将有利于雾化质量的改善,空气的供给量、点火区域和燃烧室温度的控制。作为化学动力学的重要参数,化学反应速率常数是燃烧化学中的一项重要科学数据。此外,非谐振效应在单分子解离,尤其是在团簇分子中的重要性日益显著。本论文根据RRKM (Rice-Ramsperger-Kassel-Marcus)理论,用YL方法分别计算了单分子反应体系M2+(H2O)2(M=Be, Mg, Ca), CF3XCF2CH3(X=Cl,Br)和 CF3XCF2CD3(X=Cl, B r), CH3OOH 和 CD3OOD, CH2OHCH2OH, CH2OHCHOHCH2OH 和 CH3OCH3的速率常数,并且对反应体系的非谐振效应进行了研究。首先,用Gaussian03软件在MP2/6-311G(d,p), B3LYP/6-311++G(d,p), MP2/6-311++G(3df,3pd) , MP2/6-311++G(d,p) , MP2/6-311G(d,p)和MP2/6-311++G(3df,3pd)水平上分别对上述单分子反应体系的所有反应物和过渡态的构型进行优化,进而得到各个构型的简谐和非谐振振动频率。其次,用CCSD(T)或 CBS-QB3方法对优化后构型的单点能重新进行计算,该值经零点能修正后,继而得到各个单分子反应的势垒。最后,计算得出各个单分子反应的微正则系综总态数、态密度、速率常数以及正则系综速率常数。结果显示：(1)反应的速率常数随着系统温度的增加而增加,但其增长率却逐渐减小。(2)对于反应物分子结构相似的单分子解离反应而言,反应物分子的对称性越好,反应的非谐振效应越小。(3)在反应物分子D代情况下,反应体系的非谐振效应发生变化,也就是说同位素效应对于非谐振效应具有一定的影响。
[Abstract]:Combustion plays an irreplaceable role in daily life. Currently, about 90% of the world's energy is generated by combustion. Combustion is widely used, almost all the power production human needs, involving the combustion of fuel. The engine is an important thermal power device for generating energy from fuel combustion in the power production required by human beings. The essence of fuel combustion in an engine is chemical reaction. Therefore, the study of chemical reaction kinetics of fuel combustion is of great significance to improve combustion efficiency, reduce pollutant emissions and find alternative fuels. In the process of engine fuel combustion, the high temperature pyrolysis process is very important. The study of chemical reaction kinetics will be beneficial to the improvement of atomization quality, air supply, ignition area and combustion chamber temperature control. As an important parameter of chemical kinetics, chemical reaction rate constant is an important scientific data in combustion chemistry. In addition, the non-resonance effect is becoming more and more important in the dissociation of monolayers, especially in cluster molecules. Based on the RRKM (Rice-Ramsperger-Kassel-Marcus) theory, the rate constants of M _ 2 (H _ 2O) _ 2 (MRRKM, Mg, Ca), CF3XCF2CH3 (Mg, Ca), CF3XCF2CH3) and CF3XCF2CD3 (X _ nCl _ l, B r), CH3OOH, CD3OOD, CH2OHCH2OH, CH2OHCHOHCH2OH and CH3OCH3) have been calculated by YL method, respectively. The non-resonance effect of the reaction system is also studied. First of all, using Gaussian03 software in MP2/6-311G (DNP), B3LYP/6-311 G (dapp), MP2/6-311 G (3dfU 3pd), MP2/6-311 G (dapp), MP2/6-311G (dapp) and MP2/6-311 G (3df. The configurations of all the reactants and transition states are optimized at the 3pd level, and the harmonic and non-resonant vibration frequencies of each configuration are obtained. Secondly, the single point energy of the optimized configuration is recalculated by CCSD (T) or CBS-QB3 method. After the zero energy is corrected, the potential barriers of each monolayer reaction are obtained. Finally, the total number of states, the density of states, the rate constant and the regular ensemble rate constant of each monolayer reaction are calculated. The results show that: (1) the rate constant of the reaction increases with the increase of the system temperature, but the growth rate decreases gradually. (2) for the monolayer dissociation reaction with similar molecular structure, the better the symmetry of the reactant molecule is. (3) in the case of D generation of reactants, the non-resonance effect of the reaction system changes, that is to say, the isotope effect has a certain influence on the non-resonant effect.
【学位授予单位】：大连海事大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TK401

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