【摘 要】
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During the design of pipeline,the determination of local resistant coefficient is often come arcoss. Thernsudden enlargement local resistant coefficient ζ1 = [
【机 构】
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Northeast Agricultural University, Harbin 150030,PRC
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During the design of pipeline,the determination of local resistant coefficient is often come arcoss. Thernsudden enlargement local resistant coefficient ζ1 = [1A1-A2]2rnis determined through theory. In the paper,thernsudden enlargement local resistant coefficient under the conditions of three kinds of A1-A2 was studied in rnexperi-ment. In the end ,the result shows that ζ1 is related not only to two flow cross sections ,but also to the velocirnresearch ,the relationship between ζ1A1-A2 and V1 was determined. In a word ,the hy-draulic calculation of pipeline can be done by taking correspondent ζ1 ,according to the design velocity V1 and A1/A2.
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