non-linear fluid flow through porous medium

例句：

1. 1.The flow of the fluid is non-linear due to the presence of obstacles.
   流体流动由于障碍物的存在是非直线的。
2. 2. The model assumes a non-linear relationship between temperature and humidity.
   该模型假设温度和湿度之间存在非线性关系。
3. 3. The data shows that the system operates in a non-linear manner.
   数据显示该系统以非线性方式运行。