冰期明渠水温模型

正确模拟明渠水温是分析冰情及优化调蓄水库布局的基础.基于历史气象资料,本文提出了水体与大气热交换的线性化模型和非线性模型,这些模型包含了太阳辐射、长波辐射、蒸发和对流热交换等主要因素.建立了水体与混凝土衬砌渠道热交换的参数化模型,考虑了衬砌结构、导热性能和地温等因素的影响.在此基础上,建立了明渠一维流动水温模型,提出了...

Water temperature models of open channels in glacial period

Correct simulation of water temperature in open channel is the basis for analyzing ice condition and optimizing the layout of storage reservoirs. Based on the historical atmosphere data, a linear model and a nonlinear model of heat exchange between water and atmosphere are proposed in this paper, including the influence of solar radiation, long-wave radiation, evaporation and convective heat exchange. A parameterized model of heat exchange between water body and concrete lining is established, taking into account the influence of lining structure, thermal conductivity and ground temperature. On this basis, the one-dimensional flow water temperature model of open channel is established, and the critical temperature criterion for water temperature change is proposed. Then, the recursive formula for numerical calculation of open channel water temperature is obtained by analyzing the characteristic line method. The critical length formula of water temperature from positive to negative under the condition of uniform flow is put forward, and the effects of air temperature, channel inlet water temperature, earth temperature and solar radiation on the critical length are analyzed. Finally, the effects of nonlinear heat exchange model and linear heat exchange model on the critical length are compared with a typical example.