Instability of flow with temperature‐dependent viscosity: A model of magma dynamics
Instability of flow with temperature‐dependent viscosity: A model of magma dynamics
复制标题
具有与温度相关的粘度的流动不稳定性：岩浆动力学模型
DOI：
10.1029/90jb02342
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发表时间：
1991
影响因子：
--
通讯作者：
K. Helfrich
中科院分区：
文献类型：
--
作者：
J. Whitehead;K. Helfrich
在粘度与温度非常相关的材料中，从腔室通过冷却槽的流动可能产生指进不稳定性或时间相关行为，这取决于腔室的弹性特性、粘度-温度关系和槽的几何形状。描述了一项实验室实验，其中糖浆在恒压下从储液器流过浸入冷冻浴中的管子到达出口孔。流动是稳定的或周期性的，这取决于浴的温度和进入储液器的流速。理论表明，从稳定到周期性流动的过渡取决于压力和流量之间的稳态关系中的非线性。一个一般的稳定性标准是先进的，指出Peclet数必须在一定范围内的不稳定发展。决定振荡周期的参数。理论还表明，在某些条件下，通过缝隙的流动会出现指状不稳定性。定性实验室实验与石蜡铺展在冷板揭示了指进。
In material whose viscosity is very temperature dependent, flow from a chamber through a cooled slot can develop a fingering instability or time-dependent behavior, depending on the elastic properties of the chamber, the viscosity-temperature relationship, and the geometry of the slot. A laboratory experiment is described where syrup flows from a reservoir through a tube immersed in a chilled bath to an exit hole at constant pressure. Flow is either steady or periodic depending on the temperature of the bath and the flow rate into the reservoir. A theory indicates that the transition from steady to periodic flow depends on nonlinearities in the steady state relation between pressure and flow rate. A general stability criterion is advanced that states that the Peclet number must be within a certain range for instability to develop. Parameters governing the oscillation period are determined. Theory also indicates that flow through a slot would develop finger-like instabilities under certain conditions. Qualitative laboratory experiments with paraffin spreading over a cold plate reveal the fingering.