【摘 要】
:
在胶凝温度以下,因蜡的结晶析出并形成三维空间网络结构,含蜡原油表现出复杂的非牛顿流体特性,如黏弹性、屈服应力和触变性等。目前,含蜡原油的触变性模型均为黏塑性模型,没
【机 构】
:
中国石油大学(北京)油气管道输送安全国家工程实验室
【基金项目】
:
国家自然科学基金重点项目(51134006).
论文部分内容阅读
在胶凝温度以下,因蜡的结晶析出并形成三维空间网络结构,含蜡原油表现出复杂的非牛顿流体特性,如黏弹性、屈服应力和触变性等。目前,含蜡原油的触变性模型均为黏塑性模型,没有考虑屈服点附近及之前物料所具有的黏弹特性。为此,提出了一个包含状态方程和速率方程、共10个未知参数的黏弹-触变模型。模型的剪应力由弹性应力和黏性应力构成,弹性应力为剪切模量与剪应变的乘积,剪切模量正比于结构参数和损耗函数。描述结构参数随时间变化的速率方程,假设结构破坏项与能量耗散率相关,克服了以往速率方程中结构破坏项与剪切率相关这一假设的不足
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