Feasibility Study of a "Snow Dam" Concept

近年来，在日本，人们对将雪用于各种目的，以更好地服务于多雪地区的生活越来越感兴趣。本研究报告了一个全新的想法，收集和储存雪作为“雪坝”，并利用延迟的融水补充夏季的用水需求的可行性。这个想法不是建立一个像混凝土坝一样的结构，而是在适当的选址条件和技术的峡谷中收集雪。需要技术来收集峡谷中的雪并降低融化速度，以便在最需要的时候提取水来提供供应。各种技术进行了审查。结果表明，法国研制的Gaz.ex雪崩爆破装置是一种很有前途的雪崩爆破技术，但其能收集的雪量还有待于进一步的实验研究;建立了粉雪雪崩的流体动力学模型，预测了粉雪雪崩的碎片体积、雪崩的行进高度和速度。该模型考虑了山坡的三维地形。它包括动量平衡的二维处理、空气和雪的质量守恒方程和湍流能量守恒的近似方程，控制和延缓融化的技术包括处理雪坝和预测融雪径流。后者需要对峡谷深处的大坝进行小尺度径流分析研究，而且计算必须在整个夏季进行。一个分布式融雪径流模型的开发和应用到几个概念性的雪坝，它考虑到地形和气象分布。1990年4月3日开始的中野河流域的融雪计算表明，概念上的雪坝增加了夏季至8月的流量。

Recently in Japan, there is a mounting interest in using snow for various purposes that better serve life in snowy areas. This study reports feasibility of a totally new idea of gathering and storing snow as a "snow dam" , and using the delayd meltwater to supplement water demand in summer.The idea is not to build a structure that stands like a concrete dam, but to gather snow in gorges where siting conditions and technology are appropriate. Technology is needed both to gather snow in gorges and to reduce rates of melting, so that water can be extracted to provide a supply when it is most needed. Various kinds of technologies are reviewed. It is concluded that Gaz.ex, an avalanche-blasting device recently developed in France, appears a promising technology for this purpose and that further experimental studies should be needed for getting a quantitative answer as to how much snow can be gathered.A fluid dynamical model of powder-snow avalanches is developed for prediction of the debris volume and the running course height and speed of the artificial avalanches. This model takes into account three-dimensional topography of mountain slopes. It consists of the two-dimensional treatment of momentum balance, the mass conservation equations of air and snow, and an approximate equation of conservation of turbulent energy.Technology to control and delay the melting consists of treating snow dams and predicting snowmelt runoff. The latter requires research on small-scale runoff analysis in a dam located deep in a gorge, and the calculation has to be done well through the summer season. A distribution snow melt runoff model was developed and applied to several conceptual snow dams, which takes into account both topographical and meteorological distributions. A snowmelt calculation in the Nakano River basin started on April 3,1990, demonstrates that the conceptual snow dams increase summer stream flow well into August.