METAMODELLING APPROACH TO DESIGN THE ALLUVIAL CHANNELS AT INCIPIENT MOTION  

作　　者：Achanta Ramakrishna RAO Bimlesh KUMAR Gopu SREENIVASULU 

机构地区：[1]Prof., Civil department, IISc, India [2]Research Scholar, Civil department, IISc, India

出　　处：《International Journal of Sediment Research》2007年第3期218-227,共10页国际泥沙研究（英文版）

摘　　要：The design of an alluvial channel for critical conditions requires information about four basic parameters, i.e., particle size d, water depth y, energy slope Sf and average velocity u. Most of the investigators use a standard or modified form of the critical Shields＇ parameter to define the incipient motion of a particular grain size. Shields＇ diagram describes an iterative process of determining the incipient motion parameters. To design a process that does not require iteration, one must know the resistance relationship. The absence of a universal resistance equation increases the difficulty of defining the model. Metamodelling techniques are widely used in engineering designs to simulate a complex system. This article describes a Metamodel, which employs the radial basis function （RBF） network to predict the average velocity u and energy slope Sf based on experimental data of incipient condition. With the help of the Metamodel generated by the RBF network, design curves have been presented to predict the u and Sf based on known values of the particle size and water depth. It has been found that this model improves the predictability of incipient motion.The design of an alluvial channel for critical conditions requires information about four basic parameters, i.e., particle size d, water depth y, energy slope Sf and average velocity u. Most of the investigators use a standard or modified form of the critical Shields＇ parameter to define the incipient motion of a particular grain size. Shields＇ diagram describes an iterative process of determining the incipient motion parameters. To design a process that does not require iteration, one must know the resistance relationship. The absence of a universal resistance equation increases the difficulty of defining the model. Metamodelling techniques are widely used in engineering designs to simulate a complex system. This article describes a Metamodel, which employs the radial basis function （RBF） network to predict the average velocity u and energy slope Sf based on experimental data of incipient condition. With the help of the Metamodel generated by the RBF network, design curves have been presented to predict the u and Sf based on known values of the particle size and water depth. It has been found that this model improves the predictability of incipient motion.

关 键 词：Incipient motion METAMODEL MULTIQUADRIC Prediction error Radial-Basis function Sediment transport Shields＇ diagram 

分 类 号：TV146.1[水利工程—水力学及河流动力学]