Non-thermal equilibrium two-phase flow: General formulation and application to the lithosphere-asthenosphere boundary

在莫纳什大学（澳大利亚墨尔本）3个月的休假框架内，现有的岩浆系统两相流理论将被扩展到考虑非热平衡条件。在部分熔融的地幔区域，熔体的迁移通常用低粘性流体通过高粘性可变形基质的多孔流动来描述和模拟。假设孔隙度的长度尺度足够小（晶粒尺度），以保持基体和熔体之间的热平衡。然而，由于各种过程，如沟槽或岩脉形成，这个长度尺度可能会增加，导致熔体和基体之间的非热平衡。由于在一般情况下，基体和熔体以不同的速度和方向运动，这种不平衡取决于熔体和基体流动的历史，即需要一个新的理论公式来描述该系统的能量守恒。在本项目中，将开发这样一个公式，并对其进行简化测试，并将其应用于岩石圈-软流圈边界附近部分熔融的区域。蒙纳士大学的主持人（R. Weinberg教授和A. Cruden教授）在岩浆系统领域的专业知识为本项目的合作提供了良好的环境。

Within the framework of 3 month sabbatical leave at Monash University (Melbourne, Australia) the existing theory of two phase flow of magmatic systems will be extended to account for non-thermal equilibrium conditions. Migration of melt in a partially molten mantle region is usually described and modelled by porous flow of a low viscous fluid through a highly viscous deformable matrix. The length scale of the porosity is assumed sufficiently small (grain scale) so that thermal equilibrim between matrix and melt is maintained. However, due to various processes such as channeling or dyke formation this length scale may be increased, resulting in a non-thermal equilibrium between the melt and matrix. Because in the general case the matrix and melt move with different speeds and directions, this disequilibrium depends on the history of melt and matrix flow, i.e. a new theoretical formulation is required to describe the energy conservation of this system. In this project such a forumlation will be developed, simplifications will be tested and applied to the partially molten region near the lithosphere-asthenosphere boundary (LAB). The expertise of the hosts at Monash (Prof. R. Weinberg, Prof. A. Cruden) in the field of magmatic systems provides an excellent environment for cooperation in this project.