关键词: 河工模型, 河道水流, 水面线, 床面, 水力模型, 过水断面, 水流运动, 几何形态, 比尺, 粗糙度

Abstract: This paper points out that if the line of water surface in a prototype river is similar to that in a model river, both prototype river and model river will satisfy the gravity similarity criterion and the resistance similarity criterion. These two criteria must be satisfied in fixed bed river models. #br# According to the Beronoulli equation we shall obtrain the result shown above, but there will be a process before we can obtain it. #br# The following is the scale relations for the fixed bed river models: #br# (1) For the geometrically similar systems: #br#δn=δl^(1/6) or δλ=1 #br# (2) For the so-called distorted river models (here δl ≠δh): δn=（1/δl)^(1/2)(Rp/Rm)^(2/3) or #br# δλ=(1/δl)(Rp/Rm) #br# All these various formulae are based on the Bornoulli equation.