TURBULENCE MEASUREMENT INSTRUMENT WITH A SILICON PIEZORE-SISTANCE BEAM

A newly developed turbulence measurement instrument is introduced in the paper.The transducer of the device is based on the principle of the effect of silicon piezoresistance that isintegrated in a Wheatstone bridge on a pure silicon beam. At one end of the beam, a small lightball is installed as the target forced by the water flow. The other parts are prevented from thewater flow with a sophisticated stainless steel tube. The instrument can be used to measure turbu-lent velocities either in clear Water or in flows bearing hyperconcentration of sediment. It can al-so be used to measure velocities in both glass flume and model experiments as well as in pipe ex-periment by being mounted in a special way.     

MODEL EXPERIMENT RESEARCH ON CROSS FRACTURE FLOW

This paper gives emphasis on the research of the problem of local head loss of cross fracture flow by a lot of model experiments,and a theoretical model of local head loss of cross fracture flow is founded by use of the momentum law of water flow.Through the correlation analysis between model experimental results and theoretical model,the correction coefficient of theoretical model is definite.The proposed calculation formula of local head loss of cross fracture flow can be used to analyze the problem of network fracture seepage.     

NUMERICAL SIMULATION OF 2-D TIDAL FLOW AND WATER QUALITY UNDER THE CURVILINEAR COORDINATES

This paper presents a numerical method to simulate the 2-D tidal flow and water quality under the curvilinear coordinates. In order to overcome the computational difficulties in natural rivers, such as the complicated boundary figures, the great disparity between length and width of computational domain, etc. , boundary-fitted grid is used, the irregular domain in physical plane is transformed into a rectangular domain in transformed plane, and the depth-averaged momentum equations and mass equation are rewritten and discretized based on the finite volume techniques in curvilinear coordinates. Practical application of the method is illustrated by an example for the Dachangzhen Section of the Yangtze River. A fair agreement between the values measured and computed demonstrates the validity of the method developed.     

关于地震主动动土压力计算公式探讨

水工建筑物地震主动动土压力计算较为复杂，在现行《水工建筑物抗震设计规范》中提供的计算公式存在一定缺陷。通过大量计算分析及验证，对现行规范计算公式提出了改进意见，供大家借鉴。