羧酸酯分子结构有限元分析及液体热导率估算

Finite element analysis of molecular structure and estimation of liquid thermal conductivity of carboxylates

在化工生产中热导率是基本的热力学数据。羧酸酯类有机物是重要的化工原料,但对其热导率的估算研究较少。作者在有限元分析方法基础上,用振动力学方法求解羧酸酯分子结构固有频率,用势能最小原理求解各节点的位移矢量,用量化计算方法中的重原子集居电荷计算羧酸酯分子结构的电荷-位移参量,建立了羧酸酯类有机物液体热导率的估算模型。结果表明,用羧酸酯分子结构固有频率、电荷-位移、温度等参量建立的液体热导率估算模型,不仅对48个羧酸酯分子在不同温度下的746个液体热导率数据具有较好的相关性、显著性和稳定性,而且对训练集以外的羧酸酯分子液体热导率具有很好的预测性。估算结果与Sastri方法和Latini方法比较,不仅相对误差明显减小,而且估算条件简化,可适用的估算范围得到扩大,目标分子结构可以更为复杂。

Thermal conductivity is a basic thermodynamic data in chemical engineering.Carboxylates are important organic raw materials,while its thermal conductivity estimation is limited.Based on finite element analysis,the natural frequency of carboxylate molecular structure was solved by vibration mechanics,and the displacement vector of each node was solved by potential energy minimum principle and the charge-displacement parameter of carboxylate molecular structures was calculated by heavy atomic charge of the quantum calculation method.The results show that the liquid thermal conductivity estimation model based on natural frequency of carboxylic acid ester molecules,charge-displacement and temperature parameters are applicable for the correlation of 48 carboxylates of 746 liquid thermal conductivity data at different temperatures,it can also be used for the prediction of liquid thermal conductivity of carboxylates not in the training set.Compared with Sastri and Latini methods,the result shows that the error is smaller,the estimation condition is simpler,the estimation range is wider and the target molecule structure is more complex.