| The groundwater flow and solute transport in the fractured media is an important research aspect in hydrogeology of nowadays, the result of which has important instructional significance on deep underground projects, prevention and cure of groundwater pollution and geologically treatment of radionuclide waste. This study is supported by Natural Science Foundation of China and Fok Ying Tung Education Foundation. Base on the conclusion from laboratory experiment, field tests and numerical simulation that channel flow is found both in fracture network and a single fracture, in which case the tranditional parallel-plate model is unsuitable any more because of the heterogenity of fracture rock, this paper design and carry out the experiment of flow in a single fracture channel physical model. It is found that (1) Reynolds number between channel model and tranditional model presents obvious difference and the judement of transition and turbulent area make mistake when channel flow is found. (2) Because of the special structure of channel ,the range of Darcy flow is so small that it will evolve swiftly to non-Darcy flow when waterpower gradient change. (3) The critical Reynolds number decreased with the increase of contact area ratio. (3) The result of logarithmic curve fitting on dispersion versus average velocity m is 1.3～1.9, which show that water flow state is non-Darcy, the same as that showing by dye trace test.(4)The relationship between dispersion and velocity appear linear or nonlinear in differet hydraulic condition, and quadratic term relation is found in the nonlinear area. (5)The traditional model ADE can simulate the tailing effect but not the multimodal phenomena. (6)Scale effect of dispersion is shown in the experiment and accord with DL=10-nLm. It's also found that the scale effect of dispersion is related with waterflow state and framework of fracture surface.
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