集中水流冲刷条件下浅沟径流流速特征研究  

Ephemeral Gully Flow Velocity under Concentrated Water Flow

作　　者：董月群[1] 雷廷武[1] 张晴雯[2] 颜燕[1] 刘芳芳[1] 

机构地区：[1]中国农业大学水利与土木工程学院,北京100083 [2]中国农业科学院农业环境与可持续发展研究所,北京100081

出　　处：《农业机械学报》2013年第5期96-100,共5页Transactions of the Chinese Society for Agricultural Machinery

基　　金：黄河水利委员会治黄专项资助项目(黄水保[2007]19号);中国农业大学研究生科研创新专项资助项目(KYCX2011086)

摘　　要：在室内不同坡度和径流流量条件下,用电解质示踪法和染色剂示踪法进行浅沟径流流速测量的对比研究。用采自北京的粉壤土在室内试验模拟浅沟侵蚀,测量并计算浅沟径流流速。在坡度5°、10°、20°,流量64、128、256 L/min条件下,进行浅沟水流流速的测定试验。测量结果表明,浅沟径流流速随坡长增加略有减小,随流量和坡度增大而增大。电解质示踪法测量得到的流速在0.55～1.60 m/s之间,而染色剂示踪法测量得到的流速为0.71～1.45 m/s,染色剂示踪法测量得到的流速略小于电解质示踪法测量结果。考虑到浅沟水流对示踪剂稀释及紊流对水流的扰动造成的视觉影响,电解质示踪法测量的流速具有其合理性。A series of flume experiments with a silt loam taken from Beijing were conducted to measure water flow velocity with two methods, the electrolyte tracer method and dye tracer method. A solute injector, a data logger for control and data acquisition was used for flow velocity measurement. The experiment involved three slope gradients （5°, 10° and 20°）, and three flow rates （64 L/min, 128 L/min and 256 L/min）. The results showed that the velocity of ephemeral gully water flow tended to decrease with slope length. The velocity increased with flow rate and slope gradient. The velocity measured by the electrolyte tracer method under the given experimental condition ranged from 0.55 m/s to 1.60 m/s, as compared with 0.71 m/s to 1.45 m/s by the dye tracer method. The velocities measured by the two methods were compared under different slope gradients and flow rates. The velocities measured by the dye tracer tended to be lower than those measured by the electrolyte tracer method. Considering the strong dilution and disturb effects of high rate water flow and strong turbulence on dye tracer, visual detection of dye movement should have caused later detection of the dye movement in water flow. All these indicate that the measured velocity of ephemeral flow seems rational.

关 键 词：浅沟侵蚀 径流 流速 电解质示踪法 

分 类 号：S152.7[农业科学—土壤学] S157[农业科学—农业基础科学]