Abstract:
Heavy tail is an important topic of solute transport. Spatial structures like the immobile domain and lenticle lense will lead to the heterogeneity of porous media which results in the distribution of heavy tail. Finger flow caused by variation of density will also lead to heavy tail. Based on the above theory, this paper chooses NaCl as the tracer since it is a kind of conservative solute. The sand column experiment is used to study the influences of the immobile domain, concentration and temperature on solute transport. The results show that the immobile domain will lead to the delay of the breakthrough curves, the reduction of peak and the distribution of heavy tail. The larger the amount of the immobile domain is, the more obvious the heavy tail is. The higher the concentration is, the more obvious the heavy tail is. The heavy tail will be intensified with a higher temperature. Among all the influence factors, the immobile domain mostly influences the distribution of solute transport more, and concentration and temperature follow.