Numerical Study Of Flow And Heat Transfer In The Near Field Of Nuclear Waste Repository In Saturated Rock With Fault

This paper mainly presents the research based on the the deep geological disposal of high level radioactive waste, in the numerical simulation we need to change the parameters of the faulted zone (including permeability, position, dip, width) in order to find the character of flow and heat transfer in the near field of nuclear waste repository in saturated rock with fault.The mainly conclusions are:When heat flux affects the boundary, it can not pass over the faulted zone and affect the other rock mass in the condition of high permeability coefficient value, the temperature gradient within the fault zone is very small,the temperature of the faullt zone is nearly eaqul to the temperature of bottom boundary;it can pass over the faulted zone and affect the other rock mass in the condition of medium value but the convective heat role of the flow in the faulted zone should not be ignored; in the low value the final temperature field is nearly exactly as the field without the faulted zone, and the convective heat role of the flow in the faulted zone can be ignored. With larger permeability coefficient, the heat transfer to boundary required shorter time, and the temperature of the faullt zone is smaller.Set two unsymmetric faults in the model, through the duration which heat transfer to boundary to get the impact to the temperature field of the zone by the distance D between faulted zone and the center of heat source,the faulted zone width d and the permeability coefficient k.With two faults at left and right zone,if the water flow through the two faults in per unit time is equal, that's to say, the product of the permeability coefficient k and the faulted zone width d is constant, than we can consider the coefficient k and d of the left and right falut are equal in order to simplify the model.Especially in the condition of high or medium permeability coefficient value,the outcome of the simplification is very close to what before it, the temperature difference between the two faults is within 5%. That's to say,the impact to the temperature field of the zone ofκand d is linear. The relationship between the impact,which is exerted by D, on the whole temperature field and other two parameters are nonlinear.The impact of faulted zone dip to the final temperature field. In the condition of same Infiltration water pressure, the horizontal faulted zone is much larger than the vertical faulted zone; if the angle of vertical faulted zone is different, the nearer the lower faulted zone to the heat, the shorter time the faulted zone affects the boundary temperature, however, almost no significant difference between the final temperature.