Study on Mechanism of Rainwater Drinage in Thatched Roof and Aplication

为弄清杆式茅草屋的排水机理，首次研制了人工造雨装置，对杆式茅草屋的雨水行为进行了研究。其次，排水能力的玻璃杆或不锈钢杆茅草屋顶，这是用来代替茅草屋顶，在不同的距离杆，间距和layrs。最后，我们试图通过数值模拟来解释杆草屋面系统的排水机理。所得结果如下。(1)雨水在屋顶中的行为可以从两个观点来解释，即沿着杆流动和渗透到屋顶中。(2)对于沿着杆流动，我们发现有两种流动形式，即定常连续流动和非定常间断流动。(3)对于渗透到屋顶的水，合适的杆的距离被发现，有效地保持水。这就是为什么在屋顶中的杆的特定距离处观察到最高的排水能力。雨水随机渗透，福尔斯落在杆下的缝隙中，可以用概率来理解。(4)本文提出了一个描述雨水在杆式茅草屋顶中运动的二维模型，并尝试对该模型进行模拟。通过与试验结果的比较，认为该模型可以定量描述杆茅草屋顶的雨水行为。

The behavior of rainwater in a rod-thatched roof was investigaed to make clear the mechanism of water drainage of it. The apparatus that artificialy produces rainfalls was first develped for the research. Next, the abilities of drainage were measured for glass rod or stainless steel-rod thatches, which are used instead of a grass thatch, at various distances of rods, pitches and layrs. We finally tried to explain the drainage mechanism of rod-thatched roof systems through numerical simulation. The results obtained are as follows.(1) Behavior of rainwater in a roof can be explained from the two standpoints sicj as a fow along rods and penetration into a roof.(2) As for a flow along rods, We found out the two types of flow, namely, a steady continuous flow and an unsteady disconnected flow.(3) As for the water penetration into a roof, suitable distance of rods was found that holds water efficiently. This is the reason the hghestdrainage ability was observed at a particular distance of rods in a roof. Rainwater penetrates randomly falls down in gaps of beneath rods and it can be understood in terms of probabiities.(4) We proposed a two-dimensiona model of expressing the behavior of rainwater in a rod-thatch roof, and tried to simulate the behavior. Comparing to the test results, the model is considered to be available to describe quantitatively the behavior of rainwater in a rod-thatch roof.