Directional solidification occurs in industrial and natural processes, such as freeze-casting, metal processing, biological cryopreservation and freezing of soils. Translational temperature gradient stage allows to control the process of directional solidification and to visualise it with optical microscope. In this stage freezing velocity and temperature gradient are decoupled and are independently controlled. Here we study the dynamics of the phase transition interface in thin water samples using translational temperature gradient stage. We follow position of the ice-water interface with optical microscopy and compare it to solution of one dimensional Stefan problem in the low velocity limit. We find an agreement between experimental observations and theoretical predictions for constant velocity and during acceleration of the ice front. This work presents a practical framework for analysis and design of experiments on a translational temperature gradient stage.

中文翻译：

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平移温度梯度阶段单向冻结和熔化动力学的热通量平衡描述

定向凝固发生在工业和自然过程中，例如冷冻铸造、金属加工、生物冷冻保存和土壤冷冻。平移温度梯度阶段允许控制定向凝固过程并用光学显微镜对其进行可视化。在这个阶段，冷冻速度和温度梯度是分离的，并且是独立控制的。在这里，我们使用平移温度梯度阶段研究薄水样中相变界面的动力学。我们用光学显微镜跟踪冰水界面的位置，并将其与低速极限中的一维 Stefan 问题的解决方案进行比较。我们发现在恒定速度和冰锋加速期间的实验观察和理论预测之间存在一致。