Rheological properties of elastoviscoplastic liquid in tubes
管内弹粘塑性液体流变特性研究

摘要

许多流体动力学过程都与液体特性息息相关,而液体的机械和物理特性可以通过建立不同模型来描述，通过研究相关的模型，可以描述部分流体力学的过程。本文通过建立一个力学模型，定性分析不同系统中发生的形变过程，用来研究连续介质运动的封闭理论，特别是应力和应变之间的运动。常见的力学模型有：弹性模型、粘性模型和塑性模型，而力学模型是以胡克定律为理论依据，建立相关模型来显示弹性体的力学状态。实践表明，有更为复杂的流体不遵守这一定律，这些流体之一是弹粘塑性流体。本研究通过建立一个力学模型来描述液体的弹粘塑性特性。通过计算弹粘塑性流体的总应力，即计算弹性变形对应的应力与粘塑性阻的方程，用于计算部分管道的速度和给定液体的体积流量。计算表明，随着可压缩性的增加，液体的流速部分增加，从而在所提出的模型的基础上，使得在考虑体积弹性膨胀系数的情况下，模型仍具有积极的效果。

Abstract

Many fluid dynamic processes are closely related to the characteristics of liquids, and the mechanical and physical properties of liquids can be described by establishing different models, through the study of relevant models, part of the fluid dynamics process can be described. In this paper, a mechanical model is established to qualitatively analyze the deformation process occurring in different systems, which is used to study the closed theory of continuum motion, especially the motion between stress and strain. The common mechanical models are elastic model, viscous model and plastic model, and the mechanical model is based on Hooke's law to establish a relevant model to show the mechanical state of the elastic body. Practice has shown that there are more complex fluids that do not obey this law, and one of these fluids is an elastic-viscoplastic fluid. In this study, a mechanical model is established to describe the elasto-viscoplastic properties of liquids. By calculating the total stress of elasto-viscoplastic fluid, that is, the equation of calculating the stress corresponding to elastic deformation and viscoplastic resistance, it is used to calculate the velocity of some pipes and the volume flow of given liquid. The results show that with the increase of compressibility, the flow rate of the liquid partially increases. Based on the proposed model, the model still has a positive effect when the coefficient of volumetric elastic expansion is considered.