Thermal Conductivity Model for Polyurethane Insulation Material in Consideration of Moisture

WANG Hou-mi; LIU Chao; MING Feng

doi:10.11988/ckyyb.20220259

PDF(5816 KB)

Journal of Changjiang River Scientific Research Institute ›› 2023, Vol. 40 ›› Issue (8) : 157-162. DOI: 10.11988/ckyyb.20220259

Hydraulic Structure and Material

Thermal Conductivity Model for Polyurethane Insulation Material in Consideration of Moisture

WANG Hou-mi¹, LIU Chao¹, MING Feng^2,3

Author information +

History +

Abstract

Laying insulation materials is an effective measure to mitigate the freezing damage to channels. However, the absorption of moisture by insulation materials can lead to a deterioration in their thermal insulation performance. To investigate the impact of moisture content on thermal conductivity of insulation materials, a model predicting thermal conductivity taking moisture content into account was established using the homogenization method based on the minimum thermal resistance law. Furthermore, the influence of porosity and moisture content on thermal conductivity was examined. The proposed model was then validated against experimental results and an existing model. The findings reveal that thermal conductivity decreases with the increase of porosity, but increases with the increase of moisture content. The error between the predicted and measured results is less than 5%, thereby confirming the feasibility of the proposed model in calculating the thermal conductivity of insulation materials. Additionally, moisture is identified as a significant factor in diminishing the thermal insulation performance of polyurethane rigid foam. Consequently, enhancing the hydrophobic properties of insulation materials holds great practical significance in improving its thermal insulation performance. Several suggestions are put forward to enhance the hydrophobicity of polyurethane insulation materials.

Key words

canal / insulation material / thermal conductivity / polyurethane / prediction model

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

WANG Hou-mi, LIU Chao, MING Feng. Thermal Conductivity Model for Polyurethane Insulation Material in Consideration of Moisture[J]. Journal of Changjiang River Scientific Research Institute. 2023, 40(8): 157-162 https://doi.org/10.11988/ckyyb.20220259

References

[1] 杨晓松, 杨保存, 王正中, 等. 考虑太阳辐射的寒区混凝土衬砌渠道冻害机理[J]. 长江科学院院报, 2016, 33(6):41-46, 52.
[2] 汪恩良, 靳婉莹, 韩红卫, 等. 寒区衬砌渠道冻害防治技术研究进展[J]. 黑龙江大学工程学报, 2018, 9(2): 86-91.
[3] LI S, ZHANG M, TIAN Y,et al. Experimental and Numerical Investigations on Frost Damage Mechanism of a Canal in Cold Regions[J]. Cold Regions Science and Technology, 2015, 116: 1-11.
[4] 石娇, 张希栋, 甄志磊, 等. 基于温度-应力耦合的冻土地区渠道衬砌防冻胀效果及适应性评价[J]. 长江科学院院报, 2022, 39(3):131-136, 142.
[5] 赵波, 李敬玮, 孟川, 等. 渠道保温材料保温性能演化规律的试验研究[J]. 中国水利水电科学研究院学报, 2017, 15(5):354-359.
[6] 杨金龙, 米海惠, 苏振国, 等. 含水率对建筑外墙保温材料导热性能的影响[J]. 建筑材料学报, 2017, 20(6): 986-990.
[7] 王志国, 张佳, 秦芮. 保温多孔材料含湿传热过程分析模型[J]. 功能材料, 2019, 50(7):7017-7023.
[8] 黄坤, 白宇帅, 张春云, 等. 多孔介质等效导热系数研究进展[J]. 东北电力大学学报, 2021, 41(4):1-15.
[9] 韩国库, 许健, 仇鹏, 等. 新型渠道保温防渗材料导热性能试验研究[J]. 中国水运(下半月), 2018, 18(8): 169-170.
[10] SHIN A H-C, KODIDE U. Thermal Conductivity of Ternary Mixtures for Concrete Pavements[J]. Cement and Concrete Composites, 2012, 34(4): 575-582.
[11] TAOUKIL D, EL BOUARDI A, SICK F, et al. Moisture Content Influence on the Thermal Conductivity and Diffusivity of Wood-Concrete Composite[J]. Construction and Building Materials, 2013, 48: 104-115.
[12] ROTTMANN M, BEIKIRCHER T, EBERT H-P. Thermal Conductivity of Evacuated Expanded Perlite Measured with Guarded-Hot-Plate and Transient-Hot-Wire Method at Temperatures between 295 K and 1073 K[J]. International Journal of Thermal Sciences, 2020, 152: 106338.
[13] 杨正宏,李婷婷,于龙.低密度泡沫混凝土导热系数模型研究[J].建筑材料学报,2020,23(2):322-327.
[14] BOURIH K, KADDOURI W, KANIT T, et al. Modelling of Void Shape Effect on Effective Thermal Conductivity of Lotus-Type Porous Materials[J]. Mechanics of Materials, 2020, 151: 103626.
[15] SHEN Y, XU P, QIU S,et al. A Generalized Thermal Conductivity Model for Unsaturated Porous Media with Fractal Geometry[J]. International Journal of Heat and Mass Transfer, 2020, 152: 119540.
[16] 陈瑞,宫经伟.基于细观复合材料的寒区混凝土导热系数模型[J].长江科学院院报,2020,37(9):142-148.
[17] CHIKHI M. Effective Thermal Conductivity of Porous Biomaterials: Numerical Investigation[J]. Journal of Building Engineering, 2020, 32: 101763.
[18] CARSON J K, LOVATT S J, TANNER D J,et al. An Analysis of the Influence of Material Structure on the Effective Thermal Conductivity of Theoretical Porous Materials Using Finite Element Simulations[J]. International Journal of Refrigeration, 2003, 26(8): 873-880.
[19] 龚建清, 张婵韬. 玻化微珠保温砂浆导热系数模型研究[J]. 湖南大学学报(自然科学版), 2014, 41(6): 99-105.
[20] KAROGLOU M,MOROPOULOU A,MAROULIS Z B,et al. Water Sorption Isotherms of Some Building Materials[J]. Drying Technology, 2005, 23(1/2): 289-303.
[21] SASS J H, LACHENBRUCH A H, MUNROE R J. Thermal Conductivity of Rocks from Measurements on Fragments and Its Application to Heat-Flow Determinations[J]. Journal of Geophysical Research, 1971, 76(14): 3391-3401.
[22] WANG Y, LIU K, LIU Y,et al. The Impact of Temperature and Relative Humidity Dependent Thermal Conductivity of Insulation Materials on Heat Transfer through the Building Envelope[J]. Journal of Building Engineering, 2022, 46: 103700.
[23] 严正, 程朝, 邱少稳, 等. 硅改性水性聚氨酯的研究进展[J]. 现代涂料与涂装, 2018, 21(7): 23-26.
[24] 王维, 王冬, 东为富. 新型疏水聚氨酯硬质泡沫的绿色制备及其性能研究[J]. 中国塑料, 2021, 35(4):23-29.