流变仪响应特性对含蜡原油屈服应力测试结果的影响

发布时间：2018-03-10 21:16

本文选题：含蜡原油　切入点：屈服特性　出处：《油气储运》2017年04期 　论文类型：期刊论文

【摘要】：含蜡原油的屈服特性对管道停输再启动起主导性作用。目前,含蜡原油屈服应力大多利用实测的流变曲线,依据某判定条件确定。利用2台同为控制应力型但不同型号的流变仪开展实验,发现在测试的初始阶段,相同剪切加载条件下不同流变仪的实际响应特性(剪切率)不同,流变曲线差别较大;分析含蜡原油在2台流变仪下的屈服响应特性,发现其屈服应力、屈服应变差别较大,即含蜡原油屈服特性与流变仪加载后的实际响应特性密切相关。因此,含蜡原油屈服应力的确定需要考虑流变仪在测试过程中的实际加载条件。基于固体力学中材料强度极限的概念,将含蜡原油黏弹-触变模型中弹性应力的最大值定义为屈服应力。新提出的确定屈服应力的方法能够考虑流变仪在测试过程中的实际加载过程,物理意义也更加明确。
[Abstract]:The yield characteristics of waxy crude oil play a leading role in pipeline shutdown and restarting. At present, the yield stress of waxy crude oil is mostly based on the measured rheological curves. According to a certain judgment condition, two rheometers which are stress controlled but of different models are used to carry out experiments. It is found that the actual response characteristics (shear rate) of different rheometers are different under the same shear loading condition in the initial stage of the test. The yield response characteristics of waxy crude oil under two rheometers are analyzed, and the yield stress and yield strain of waxy crude oil are found to be quite different. That is, the yield characteristics of waxy crude oil are closely related to the actual response characteristics of rheometer after loading. The determination of yield stress of waxy crude oil needs to consider the actual loading condition of rheometer in the testing process. Based on the concept of material strength limit in solid mechanics, The maximum value of elastic stress in viscoelastic-thixotropic model of waxy crude oil is defined as yield stress. The new method for determining yield stress can take into account the actual loading process of rheometer in the testing process and the physical meaning is more clear.
【作者单位】：中国石油大学(华东)/山东省油气储运安全省级重点实验室;
【基金】：国家自然科学基金资助项目“胶凝原油管道启动问题中关键非定常参量研究”,51574274 山东省自然科学基金资助项目“含蜡原油非线性黏弹特性研究”,2014BSE28055
【分类号】：TE81

【相似文献】