海冰盐度影响下冰水热力过程的试验研究
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摘要
北极多年海冰的渡夏与冰脊形成的初始阶段均属于海冰升温的热力学过程。在卤水作用下,海冰在升温过程中需要融化内部的固态冰以达到温盐平衡。为研究海冰升温过程中盐度对宏观热力学性质的影响,本文设计了冰块试样在水中的一维浸没试验。将具有相同初始温度(-32℃)、不同盐度(0 ppt, 2.65 ppt, 12 ppt)的冰试样浸至0.2℃的淡水环境中,并测试试样内部温度场与厚度变化。试验结果表明,高盐度海冰的最终冰厚增加量超过31%,而淡水冰则仅为15%。海冰内部卤水的活跃改变了海冰的宏观比热并大幅度提高了其潜在的内能变化量。同时,将内能变化的实测结果与Schwerdfeger模型理论计算结果进行了对比。分析得出,真实环境中在海冰卤水迁移引起的盐度不均匀分布与卤水外排使得Schwerdfeger模型无法准确描述海冰升温过程中热力学性质。此外,通过对新生冰进行冰晶测试中所观测的柱状结构及晶粒尺寸特征也进一步验证了试验结果的可靠性。
The warming-up process of sea ice widely exists in summer ice and the initial phase of ice ridge consolidation.Due to the brine migration, the internal pure ice is melted to maintain the salinity-temperature equilibrium. To study theinfluences of salinity on the thermal properties, one-dimensional submerging experiments were designed to put the icesample into the salty water. A group of ice samples with the same initial temperature(-32℃) and various salinities(0 ppt,2.65 ppt, 12 ppt) were submerged into water with 0.2℃. During each test, the ice growth and temperature profile weremeasured simultaneously. From the result, it shows that the ice growth of 12 ppt sample is more than 31% while the fresh icesample has grown around 15%. The brine action increases the specific heat of saline ice and boosts the potential of inertialenergy. Meanwhile, a comparison is done between measurements and calculation from Schwerdfeger model. It is shown thatSchwerdfeger model does not predict the thermal process properly due to the brine migration induced inhomogeneousdistribution and salt drainage. Besides, the ice texture from thin section shows that the experiments are performed well alongone dimension.
The warming-up process of sea ice widely exists in summer ice and the initial phase of ice ridge consolidation.Due to the brine migration, the internal pure ice is melted to maintain the salinity-temperature equilibrium. To study theinfluences of salinity on the thermal properties, one-dimensional submerging experiments were designed to put the icesample into the salty water. A group of ice samples with the same initial temperature(-32℃) and various salinities(0 ppt,2.65 ppt, 12 ppt) were submerged into water with 0.2℃. During each test, the ice growth and temperature profile weremeasured simultaneously. From the result, it shows that the ice growth of 12 ppt sample is more than 31% while the fresh icesample has grown around 15%. The brine action increases the specific heat of saline ice and boosts the potential of inertialenergy. Meanwhile, a comparison is done between measurements and calculation from Schwerdfeger model. It is shown thatSchwerdfeger model does not predict the thermal process properly due to the brine migration induced inhomogeneousdistribution and salt drainage. Besides, the ice texture from thin section shows that the experiments are performed well alongone dimension.
引文
Bailey,E.,D.Feltham,P.Sammonds,2010.A model for the consolidation of rafted sea ice.Journal of Geophysical Research:Oceans,115(C4).
Bailey E,Sammonds P,Feltham D,2012.The consolidation and bond strength of rafted sea ice.Cold Regions Science and Technology,83:37-48.
Eshwan R,Henry B,Peter O,et al,2015.Turbulent heat exchange between water and ice at an evolving ice-water interface.Journal of Fluid Mechanics,798:572-597.
Galley R,Else B,Geilfus N-X,et al,2015.Imaged brine inclusions in young sea ice-Shape,distribution and formation timing.Cold Regions Science and Technology,111:39-48.
Griewank P J,Notz D,2013.Insights into brine dynamics and sea ice desalination from a 1-D model study of gravity drainage.Journal of Geophysical Research:Oceans,118(7):3370-3386.
Hibler W D,Weeks W F,Mock S J,1972.Statistical aspects of sea‐ice ridge distributions.Journal of Geophysical Research,77(30):5954-5970.
H?yland K V,Liferov P,2005.On the initial phase of consolidation.Cold regions science and technology,41(1):49-59.
H?yland K V,2002.Consolidation of first-year sea ice ridges.Journal of Geophysical Research:Oceans,107(C6).
Jardon F P,Vivier F,Vancoppenolle M,et al,2013.Full-depth desalination of warm sea ice.Journal of Geophysical Research:Oceans,118(1):435-447.
Lepp?ranta M,1993.A review of analytical models of sea‐ice growth.Atmosphere-Ocean,31(1):123-138.
Lepp?ranta M,Hakala R,2012.The structure and strength of first-year ice ridges in the Baltic Sea.Cold Regions Science&Technology,20(3):295-311.
Lepp?ranta M,Lensu M,Kosloff P,et al,1995.The life story of a firstyear sea ice ridge.Cold Regions Science and Te chnology,23(3):279-290.
Liferov P,H?yland K V,2004,In-situ ice ridge scour tests:experimental set up and basic results.Cold regions science and technology,40(1):97-110.
Middleton C,Thomas C,de Wit A,et al,2016.Visualizing brine channel development and convective processes during artificial sea-ice growth using Schlieren optical methods.Journal of Glaciology,62:1-17.
Sammonds P R,Murrell S A,Rist M A,1998.Fracture of multiyear sea ice.Journal of Geophysical Research Oceans,103(C10):21795-21816.
Schwerdtfecer P,1963.The thermal properties of sea ice.Journal of Glaciology,4(36):789-807.
Shestov A,Marchenko A,2016a.The consolidation of saline ice blocks in water of varying freezing points:Laboratory experiments and computer simulations.Cold Regions Science and Technology,122:71-79.
Shestov A,Marchenko A,2016b.Thermodynamic consolidation of ice ridge keels in water at varying freezing points.Cold Regions Science and Technology.121:1-10.
Timco G,Burden R,1997.An analysis of the shapes of sea ice ridges.Cold regions science and technology,25(1):65-77.
Wiese M,Griewank P,Notz D,2015.On the thermodynamics of melting sea ice versus melting freshwater ice.Annals of Glaciology,56(69):191-199.
Yen Y C,1981.Review of thermal properties of snow,ice and sea ice,in CRREL Report.U.S.Army Cold Regions Research and Engineering Laboratory:Hanover.
季顺迎,聂建新,李锋,等,2000.渤海冰脊分析及其设计参数.中国海洋平台,6:2-6.
季顺迎,刘宏亮,许宁,等,2013.渤海海冰断裂韧度试验.水科学进展,24(3):386-391.
王昆,刘潘,金生,等,2017.基于热力学过程的渤海海冰生消模型.水科学进展,28(1):116-123.
谭冰,李志军,卢鹏,等,2012.南极冬季威德尔海西北部的冰脊表面形态.水科学进展,1:117-123.
Bailey E,Sammonds P,Feltham D,2012.The consolidation and bond strength of rafted sea ice.Cold Regions Science and Technology,83:37-48.
Eshwan R,Henry B,Peter O,et al,2015.Turbulent heat exchange between water and ice at an evolving ice-water interface.Journal of Fluid Mechanics,798:572-597.
Galley R,Else B,Geilfus N-X,et al,2015.Imaged brine inclusions in young sea ice-Shape,distribution and formation timing.Cold Regions Science and Technology,111:39-48.
Griewank P J,Notz D,2013.Insights into brine dynamics and sea ice desalination from a 1-D model study of gravity drainage.Journal of Geophysical Research:Oceans,118(7):3370-3386.
Hibler W D,Weeks W F,Mock S J,1972.Statistical aspects of sea‐ice ridge distributions.Journal of Geophysical Research,77(30):5954-5970.
H?yland K V,Liferov P,2005.On the initial phase of consolidation.Cold regions science and technology,41(1):49-59.
H?yland K V,2002.Consolidation of first-year sea ice ridges.Journal of Geophysical Research:Oceans,107(C6).
Jardon F P,Vivier F,Vancoppenolle M,et al,2013.Full-depth desalination of warm sea ice.Journal of Geophysical Research:Oceans,118(1):435-447.
Lepp?ranta M,1993.A review of analytical models of sea‐ice growth.Atmosphere-Ocean,31(1):123-138.
Lepp?ranta M,Hakala R,2012.The structure and strength of first-year ice ridges in the Baltic Sea.Cold Regions Science&Technology,20(3):295-311.
Lepp?ranta M,Lensu M,Kosloff P,et al,1995.The life story of a firstyear sea ice ridge.Cold Regions Science and Te chnology,23(3):279-290.
Liferov P,H?yland K V,2004,In-situ ice ridge scour tests:experimental set up and basic results.Cold regions science and technology,40(1):97-110.
Middleton C,Thomas C,de Wit A,et al,2016.Visualizing brine channel development and convective processes during artificial sea-ice growth using Schlieren optical methods.Journal of Glaciology,62:1-17.
Sammonds P R,Murrell S A,Rist M A,1998.Fracture of multiyear sea ice.Journal of Geophysical Research Oceans,103(C10):21795-21816.
Schwerdtfecer P,1963.The thermal properties of sea ice.Journal of Glaciology,4(36):789-807.
Shestov A,Marchenko A,2016a.The consolidation of saline ice blocks in water of varying freezing points:Laboratory experiments and computer simulations.Cold Regions Science and Technology,122:71-79.
Shestov A,Marchenko A,2016b.Thermodynamic consolidation of ice ridge keels in water at varying freezing points.Cold Regions Science and Technology.121:1-10.
Timco G,Burden R,1997.An analysis of the shapes of sea ice ridges.Cold regions science and technology,25(1):65-77.
Wiese M,Griewank P,Notz D,2015.On the thermodynamics of melting sea ice versus melting freshwater ice.Annals of Glaciology,56(69):191-199.
Yen Y C,1981.Review of thermal properties of snow,ice and sea ice,in CRREL Report.U.S.Army Cold Regions Research and Engineering Laboratory:Hanover.
季顺迎,聂建新,李锋,等,2000.渤海冰脊分析及其设计参数.中国海洋平台,6:2-6.
季顺迎,刘宏亮,许宁,等,2013.渤海海冰断裂韧度试验.水科学进展,24(3):386-391.
王昆,刘潘,金生,等,2017.基于热力学过程的渤海海冰生消模型.水科学进展,28(1):116-123.
谭冰,李志军,卢鹏,等,2012.南极冬季威德尔海西北部的冰脊表面形态.水科学进展,1:117-123.