The cross-fracture is one of the basic units of rock fracture network in the deep energy exploitation. The scientific evaluation of the fluid flow behavior of a cross-fracture is a key link in the description of the fluid flow behavior of deep fractured reservoirs. Based on the Weierstrass-Mandelbrot function and combined with 3D printing technology, numbers of cross-fracture models with different roughness levels controlled by the fractal dimension are developed. A new calculation method of the pressure-drop loss coefficient is proposed, and the competitive flow diversion behavior and fluid flow state of the two branch fractures are examined with different water head ratio. The results show that the roughness difference between the cross-fracture branches is the important factor controlling the phenomenon of competitive flow diversion. Cross-flow confluence will result in a notable pressure-drop loss, and with increasing fractal dimension of the branch fracture, a larger pressure-drop loss occurs, and the rough branch fracture obtains a larger flow rate proportion. Besides, the water head ratio condition of the inlets is another important factor for the cross fracture flow. When the pressure ratio between the rough inlet and smooth outlet equals 1, the pressure-drop loss is at its maximum, and the flow rate proportion of the rough branch fracture is at its minimum, and Re gradually increases while Eu clearly decreases with increasing water pressure. When the pressure ratio between the rough inlet and smooth outlet is not equal to 1, the pressure-drop loss, the competitive flow diversion ability of the branch fracture, Re and Eu will greatly change with increasing water head ratio. The results can provide new insights into the flow through a fractured reservoir.

交叉裂缝是深部能量开采中裂缝网络的基本单元之一。对裂缝的流体流动行为进行科学评估是描述深层裂缝性储层流体流动行为的关键环节。基于Weierstrass-Mandelbrot函数，并结合3D打印技术，开发了由分形维数控制的具有不同粗糙度级别的交叉断裂模型。提出了一种新的压降损失系数计算方法，并研究了在不同水头比情况下两个分支裂缝的竞争分流行为和流体流动状态。结果表明，交叉断裂分支之间的粗糙度差异是控制竞争分流现象的重要因素。错流汇合将导致明显的压降损失，并且随着分支裂缝的分形维数的增加，发生更大的压降损失，并且粗糙的分支裂缝获得更大的流量比例。此外，入口的水头比率条件是造成交叉裂缝流动的另一个重要因素。当粗糙入口和光滑出口之间的压力比等于1时，压降损失最大，粗糙分支裂缝的流量比例最小，并且Re逐渐增加，而Eu随水的增加而明显减少压力。当粗糙的入口和光滑的出口之间的压力比不等于1时，压降损失，分支裂缝的竞争分流能力，稀土元素和Eu元素将随着水头比的增加而发生巨大变化。这些结果可以为通过裂缝性油藏的流动提供新的见解。