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用实验方法对具有不同的等效直径比β值的V锥流量计的性能(特性)进行评价。流量计的性能是雷诺数和上游干扰的函数。利用水和油作为被测介质,在一个较宽的雷诺数范围内进行实验。在V锥流量计的上游5D、10D和15D处安装有一个闸阀,利用该阀作为扰流件来研究上游速度分布对V锥流量计的影响。具体的作法是在阀的不同开度(如开度为25%、50%、75%和全开)下做实验。根据实验研究可以看出:V锥流量计的流出系数Cd几乎与雷诺数无关。对于β=0.64的V锥流量计流出系数值为0.7256±1.78%,而对于β=0.77的V锥流量计,流出系数值为0.7315±1.9%。如果在V锥流量计的上游10D或更远处装有扰流件,则不会影响流出系数值。如果在V锥流量计的上游5D处安装扰流件,则Cd值的变化约为6%。
Experimental methods were used to evaluate the performance (characteristics) of V-cone flow meters with different equivalent diameter ratio β values. Flowmeter performance is a function of Reynolds number and upstream interference. Using water and oil as the measured media, experiments were conducted over a wide range of Reynolds numbers. A gate valve was installed upstream of the V-cone flowmeter at 5D, 10D and 15D to study the effect of upstream velocity distribution on the V-cone flowmeter using this valve as a spoiler. The specific practice is to open the valve at different opening (such as the opening of 25%, 50%, 75% and fully open) under the experiment. According to the experimental study, it can be seen that the outflow coefficient Cd of the V-cone flowmeter is almost independent of the Reynolds number. For the V cone flowmeter with β = 0.64, the outflow coefficient was 0.7256 ± 1.78% and for the V cone flowmeter with β = 0.77, the outflow coefficient was 0.7315 ± 1.9%. If the spoiler is installed 10D or more upstream of the V-cone meter, the outflow coefficient will not be affected. If the spoiler is installed 5D upstream of the V cone meter, the change in Cd value is about 6%.