近十幾年來，土石流於台灣造成多次重大災害，故逐漸為人們所關心，如何防治土石流成為ㄧ個重要的議題。而不論是雪崩、山崩、土石流，目前諸多對於此類崩塌流場的研究，皆視為一個顆粒流的狀態，換句話說，就是針對一堆乾或濕的粒子所造成崩塌流場的現象去做其分析研究，所以顆粒崩塌流的研究，成為此類研究核心的部份，也是最基礎、最重要的部份。因此本研究計畫針對此類顆粒體於傾斜滑道中崩塌運動行為，進行三年期之研究。第一年的計畫將針對乾顆粒在重力驅動下於傾斜矩形流槽中的流動行為做探討，並利用在滑道上架設鏡子來反射顆粒流場狀況，進而發展出一套三維影像分析方法去針對流動中的顆粒體積佔有率做量測，以研究當顆粒體在加速運動時，體積佔有率的變化及其中物理意義。第二年及第三年計畫將進一步觀察顆粒在加速流動中遭受阻礙物的阻擋所產生的變化及影響。其中第二年計畫在矩形流槽中加入半圓柱阻礙物，讓加速流動中的顆粒流體產生震波，並分析其流場基本性質，且沿用第一年所發展出來的三維影像分析方法去計算其顆粒體積佔有率，並利用DEM模擬顆粒的運動行為，與實驗結果相比較。第三年計畫則將在平板流槽上架設不同角度之三角柱阻礙物，利用所量測出來的流場速度去獲得震波產生的位置，並與文獻所推導出來的震波理論去做驗證。本研究計畫對於土石流相關基礎研究扮演極重要的角色。而本研究室也與德國大學專業學術人員進行土石流動相關學術交流多年，再憑藉著過去十年來本實驗室所累積的豐富經驗與成果，相信可以順利執行以上研究計畫。 Rapid flows of granular materials on inclined surfaces are often encountered in engineering applications involving the mineral and food processing, bulk materials handling, and also found in geophysical situations. In the geophysical context, rock-fall, landslides and snow-slab avalanches set up to large-scale of granular materials in motion. Because of the importance of industrial and geophysical applications, granular chute flow down inclines is a popular fundamental research issue of rapid flows. This aims of the three years NSC project is to investigate the dynamics of granular down in an inclined chute. In the first year we will develop a pseudo three-dimensional measurement method to calculate the solid fraction of granular flows down an inclined rectangular chute. Comparing to the sophisticated magnetic resonance imaging (MRI) or the radioactive positron emission particle tracking (PEPT), this measurement method is verified a cost-effective and nonhazardous alternative for ordinary laboratories. The granular shock formation produced by using a fixed semi-circular cylinder obstacle in a rectangular sliding chute will be studied in the second year. The relative physical properties will be discussed and also the measurement method developed in first year project will also be applied to measure the distribution of solid fraction in granular shock. Discrete element method will also be studied and compared with experiment results in granular chute flow. In the third year, we will study the oblique granular shock by setting a triangular prism obstacle on a plane chute. The velocity field and the position of shock will be determined by PIV method. The laser sheet will be used to measure the distribution of flow height when granular flow through the oblique shock. In addition, we also will compare the experimental results with the shock theory. With the progress of this project, we wish have a great contribution to the fundamental research of debris flow. We, with a decade of relevant experiences and a robust cooperation with international institutes, are delighted to apply for it and supposed to execute the project effectively. 研究期間：10008 ~ 10107
