The Transient Analysis Of Longdistance Water Transmission System And Engineering Applications Based On AFT Impulse Software

For long-distance water pipelines, when the flow changes, the steady flow conditions will be destroyed, the steady flow conditions will change into unsteady flow conditions, that is, transient flow conditions. When the unsteady flow conditions come to a new steady flow conditions, the hydraulic parameters change dramatically, the degree of the change are beyond the constant flow designs, and will cause very negative impacts on the system., if they change too fast, the pipelines will be destroyed, and even have serious accidents. So, it is very necessary to do some research to the long-distance water pipelines.In this paper, on the basis of summing, there are detailed analysis and research on some important issues, and some corresponding conclusions. After that, based on the specific example, form a hydraulic model using specialized engineering software, adding the research results, and then, calculate and analysis of the results, give some scientific advices.This paper includes the following aspects:1. Analysis the hydraulic characteristics of the long-distance water supply system, and the mathematical method. When get the steady results, we use the Newon——Raphson method.2. Introduce some methods for getting the results of unsteady flow condition, describe and analysis the popular method: method of characteristic line, and do some derivations to the method.3. Analysis the reason and theory of cavitation, and get some mathematical model for cavitation. Then, we analysis the results with and without the cavitiation model, and get some conclusions.4. For some parts of the long-distance pipeline, such as valves, we give the transient model and the cavition model.5. Give a brief introduction of the professional engineering software, calculate the actual project, and give some scientific advices based on the conclusion results.