1.前言一般说,气体流量比液体流量更难测量,因对液体可略去压缩性、热膨胀及蒸气等复杂因素的影响。从商品流量计看,一般气体流量计的精度要低一些。但有的单位需要高精度测定气体流量,故需精密地校准流量计。气体流量校准装置从前采用气体钟罩,但受钟罩大小的限制,每分钟流量最多为几百升。更大时 1. Introduction Generally speaking, the gas flow is more difficult to measure than the liquid flow, because the liquid can be neglected compressibility, thermal expansion and steam and other complex factors. From the commodity flow meter, gas meters generally lower accuracy. However, some units need high-precision gas flow measurement, it is necessary to accurately calibrate the flow meter. Gas flow calibrators have historically been gas bellows, but are limited by bell sizes up to a few hundred liters per minute. Bigger