Rate parameters for coupled vibration-dissociation in a generalized SSH approximation. [Schwarz, Slawsky, and Herzfeld]
Rate parameters for coupled vibration-dissociation in a generalized SSH approximation. [Schwarz, Slawsky, and Herzfeld]
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广义 SSH 近似中耦合振动解离的速率参数。
DOI：
10.2514/3.312
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Chul Park
中科院分区：
文献类型：
--
作者：
S. Sharma;W. Huo;Chul Park
本文报道了氮在加热和冷却时发生非平衡弛豫过程的振动激发和解离的理论研究。碰撞引起的振动跃迁和从束缚振动状态到解离状态的跃迁的速率系数已经使用Schwarz （SSH）等人（1952）最初提出的理论的扩展来计算。高振动态和解离态被明确地包括在内，但旋转能量传递被忽略。将SSH理论计算的转移概率输入到主方程中，对主方程进行数值积分，确定振动态的总体分布和整体热力学性质。结果表明：(1)跃迁速率在结合振动能级的中间附近最小，导致了振动弛豫和解离速率的瓶颈；(2)高振动态与解离态总是处于平衡状态；(3)加热情况下，根据Landau-Teller理论，只有低振动状态松弛；(4)对于冷却情况，振动松弛不能用速率方程来描述；(5) Park（1985,1988）双温度模型近似有效；(6)在解离过程中去除的平均振动能约为解离能的30%。29日引用。«少
A theoretical study of vibrational excitations and dissociations of nitrogen undergoing a nonequilibrium relaxation process upon heating and cooling is reported. The rate coefficients for collisional induced vibrational transitions and transitions from a bound vibrational state into a dissociative state have been calculated using an extension of the theory originally proposed by Schwarz (SSH) et al. (1952). High-lying vibrational states and dissociative states were explicitly included but rotational energy transfer was neglected. The transition probabilities calculated from the SSH theory were fed into the master equation, which was integrated numerically to determine the population distribution of the vibrational states as well as bulk thermodynamic properties. The results show that: (1) the transition rates have a minimum near the middle of the bound vibrational levels, causing a bottleneck in the vibrational relaxation and dissociation rates; (2) high vibrational states are always in equilibrium with the dissociative state; (3) for the heating case, only the low vibrational states relax according to the Landau-Teller theory; (4) for the cooling case, vibrational relaxation cannot be described by a rate equation; (5) Park's (1985, 1988) two-temperature model is approximately valid; and (6) the average vibrational energy removed in dissociation is about 30 percent of themore » dissociation energy. 29 references.« less