부산대학교 도서관

Rainfall infiltration is an important source of groundwater recharge, but it is difficult to measure the infiltration rate directly in practice. For example, using traditional double-ring infiltrometers is unable to measure complete infiltration process. Installation of soil moisture meters or manometers requires experts and consumes high costs. Since the heat exchange between the groundwater and soils is incessant and affects the temperature profiles in strata (subsurface temperature profiles, STP), some studies have used the heat as a groundwater flow tracer to observe the interaction between surface water and groundwater for the past few years. Therefore, this study utilizes a distributed temperature sensing system (DTS) to measure the subsurface temperature profiles and develops a new heat-transfer analytical model combined with the optimization method to estimate in-situ infiltration rates. Moreover, this study executes an infiltration test in an experimental field built at the National Taiwan University campus. We set up three rainfall events with different rainfall patterns and compare the infiltration rate measured by a flowmeter with that estimated by the present model and method. The results show that under the different rain patterns, the curves of the estimated infiltration rate are similar to those of the measured infiltration rate. Also, the STP simulated by the developed model are consistent with a numerical model. These validate the correctness of the present method and its feasibility in field application. This estimation method has the advantage of high efficiency in calculation. The information of soil hydrogeological parameters is needless, but only that of soil thermal properties is. Finally, the developed model has more extensive applicability in boundary and initial conditions than previous models, and can become a more useful tool for groundwater infiltration analysis.