Thermal analysis of mass concrete embedded with double-layer staggered heterogeneous cooling water pipes
Thermal analysis of mass concrete embedded with double-layer staggered heterogeneous cooling water pipes
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DOI：
10.1016/j.applthermaleng.2011.10.016
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发表时间：
2012-03-01
影响因子：
6.4
通讯作者：
Li, Qingbin
中科院分区：
文献类型：
--
作者：
Yang, Jian;Hu, Yu;Li, Qingbin
施工过程中大体积混凝土水化热的排除对混凝土结构的质量和安全至关重要。基于考虑冷却水管效应和混凝土水化热影响的热传导等效方程，编制了双层错排非均质冷却水管大体积混凝土三维热分析有限元程序。根据等效冷却原理，推导了混凝土板内双层交错非均质冷却管的冷却函数。为提高小流量下等效热传导方程的适用性和精度，根据冷却函数的单调性和管流单相强迫对流换热经验公式，对冷却函数进行了修正。考虑混凝土后期水化热的影响，提出了混凝土绝热温升曲线的双指数函数拟合方法。随后，得到了混凝土的温度变化，并通过能量守恒原理估算了冷却水的出口温度。计算结果与国内某拱坝坝段实测数据的对比表明，该数值模型能够较准确地模拟大体积混凝土的温度变化。(C)2011爱思唯尔有限公司保留所有权利。
Removal of hydration heat from mass concrete during construction is important for the quality and safety of concrete structures. In this study, a three-dimensional finite element program for thermal analysis of mass concrete embedded with double-layer staggered heterogeneous cooling water pipes was developed based on the equivalent equation of heat conduction including the effect of cooling water pipes and hydration heat of concrete. The cooling function of the double-layer staggered heterogeneous cooling pipes in a concrete slab was derived from the principle of equivalent cooling. To improve the applicability and precision of the equivalent heat conduction equation under small flow, the cooling function was revised according to its monotonicity and empirical formulas of single-phase forced-convection heat transfer in tube flow. Considering heat hydration of concrete at later age, a double exponential function was proposed to fit the adiabatic temperature rise curve of concrete. Subsequently, the temperature variation of concrete was obtained, and the outlet temperature of cooling water was estimated through the energy conservation principle. Comparing calculated results with actual measured data from a monolith of an arch dam in China, the numerical model was proven to be effective in sufficiently simulating accurate temperature variations of mass concrete. (C) 2011 Elsevier Ltd. All rights reserved.