Heat and Mass Transfer of Freezing of Melting Process of Soil Containing Sea Water

含海水土壤冻结融化过程的传热传质

• 批准号: 06650264
• 负责人: OKADA Masashi
• 金额: $ 1.34万
• 依托单位: Aoyama Gakuin University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06650264/
• 关键词: Sea water; Soil; Freezing; Porous medium; Aqueous solution; Forced convection; Natural convection; Numerical analysis; 熱物質移動

Soil is one of useful materials as a heat source for a heat pump system and as a cold energy strage. For a case that thermal energy including the laten heat is stored in soil containing sea water, it is important to study a freezing or melting process of a porous medium saturated with a NaCl - aqueous solution. In the present report, considering ground water flow or the ebb and flow, effects of natural and forced convection on the freezing around a horizontal cylinder in a porous medium saturated with 3 wt% NaCl aqueous solution was investigated analytically and experimentally. In the experiments a packed bed of glass beads was used as the porous medium. In order to clarify an interaction of natural convection and forced convection, the solution was let to flow upwardor downwared across the cylinder through the porous medium with various flow rates. By cooling the cylinder below the eutectic temperature the freezing around the cylinder was initiated. In order to visualize the interactive flow around the frozen layr, and experiment of freeaing around a cylinder in Hele-Shaw flow was carried out. A numerical analysis, in which heat and mass diffusions and flow in both liquid and mushy regions were taken into account, was carried out. The temperature distributions obtained from the analysis agreed well with the experimental results. Effects of the natural and forced convection on the freezing process --- the temperature distribution, the stream function contour, the shape of frozen region, the volume fraction of liquid phase in the mushy region, and the volume fraction of eutectic solid in the solid region --- were clarified. Effects of Peclet number and the flow direction on Nusselt number and a dimensionless volume of the solid phase were clarified.

土壤是作为热泵系统热源和冷能储备的有用材料之一。对于含有海水的土壤中储存热能（包括潜热）的情况，研究NaCl水溶液饱和多孔介质的冻结或融化过程具有重要意义。本文从分析和实验两方面研究了在含3wt % NaCl饱和多孔介质中，自然对流和强制对流对水平圆柱体周围冻结的影响。实验采用玻璃微珠填充床作为多孔介质。为了阐明自然对流和强制对流的相互作用，溶液以不同的流量在多孔介质中沿圆柱体向上向下流动。通过将钢瓶冷却到共晶温度以下，钢瓶周围开始冻结。为了可视化冻结层周围的相互作用流动，在Hele-Shaw流中进行了绕柱释放实验。在数值分析中，同时考虑了液体和糊状区域的热量和质量扩散和流动。分析得到的温度分布与实验结果吻合较好。阐明了自然对流和强制对流对冻结过程的影响——温度分布、流函数轮廓、冻结区形状、糊状区液相体积分数和固体区共晶固体体积分数。阐明了Peclet数和流动方向对固相的努塞尔数和无因次体积的影响。

项目成果

Masashi Okada: "Effects of natural and forced convection on freezing around a horizontal cylinder in a porous medium saturated with aqueous solution" Fifth International Symposium on Thermal Engineering and Science for Cold Regions. (1996)

Masashi Okada：“自然和强制对流对饱和水溶液多孔介质中水平圆柱体周围冷冻的影响”第五届寒冷地区热工程与科学国际研讨会。

Masashi OKADA and Ken-ichi TSUCHIYA: "Effects of natural and forced convection of freezing around a horizontal cylinder in a porous medium saturated with aqueous solution" Fifth International Symposium on Thermal Engineering and Science for Cold Regions.

Masashi OKADA 和 Ken-ichi TSUCHIYA：“在饱和水溶液的多孔介质中水平圆柱体周围自然和强制对流冷冻的影响”第五届寒冷地区热工程与科学国际研讨会。

岡田昌志: "水溶液で満たされた粒子充填層における水平円管周りの凍結" 第32回日本伝熱シンポジウム講演論文集. 1. 233-234 (1995)

Masashi Okada：“在充满水溶液的颗粒填充床中围绕水平圆形管道进行冷冻”第 32 届日本传热研讨会论文集 1. 233-234 (1995)。

Masashi Okada: "Effects of natural and forced convection on freezing around a horizontal cylinder in a porous medium saturated with aqueous solution" Fifth Int. Symposium on Thermal Engineering and Science for Cold Regions. (1996)

Masashi Okada：“自然和强制对流对饱和水溶液的多孔介质中水平圆柱体周围冷冻的影响”第五国际。

土屋賢一: "水溶液で満たされた粒子充てん層における水平円管周りの凍結" 日本機械学会論文集B編. 61. 4123-4129 (1995)

Kenichi Tsuchiya：“在充满水溶液的颗粒填充层中冻结水平圆形管道”，日本机械工程师学会汇刊，B 版 61. 4123-4129 (1995)。