Mathematical Modeling and Numerical Analysis of Thermal Distribution in Arch Dams considering Solar Radiation Effect

Table 4

Thermal properties of dam environmental system.

Parameter	Unit	Proposed range	Initial value	Final value
Thermal conductivity coefficient of concrete	W/m °K	(1, 4)	1	1.7
Specific heat coefficient of concrete	W/hr·Kg °C	(0.1, 0.4)	0.1	0.25
Solar absorptivity coefficient of concrete	—	(0.6, 0.85)	0.6	0.7
Emissivity coefficient of concrete surface	—	(0.3, 0.9)	0.5	0.8
Diffuse reflectance coefficient (upstream face)	—	Table 2	0.3	0.3
Diffuse reflectance coefficient (downstream face)	—	Table 2	0.2	0.2
Convection coefficient of air	W/m^2 °K	(5, 25)	60*	60*
Convection coefficient of water	W/m^2 °K	Variable	6000	6000

∗Considering the wind and radiation of air convection effects leads to increasing of this parameter significantly; refer to (3).