一、前言在锅炉运行调整试验中,经常会遇到需对含尘气流进行速度、浓度等的测量。特别是在近年来直吹式制粉系统逐年增加,此问题显得更加突出。在用皮脱管或用皮脱管原理做成的测速管,对含尘气流进行测量后,用公式W=4.43(H/γ)~(1/2)计算流速时,如果用纯空气的重度γ代入上式,则上式中的动压头H 在用直接测量出的数据时,是否需要修正和如何进行修正,换一句话说,如果上式中用的是所测量出的动压头H,则重度γ是根据纯空气的γ_(?),还是含尘气流的γ(_((?)+.n)),或者是两者之间的某一个数,关于这个问题,虽然过去在杂志上曾有过报导,但意见不一致,如资料介绍,在一水平管段的试验台上专门进行了含尘气流浓度、速度、粒度对皮脱管读数影响的试验,根据试验结果,作者提出在计算流速时,动压头H 为皮脱管的读数,则重度γ为含尘气流混合物的重度;资料提到在煤粉体积浓度为500kg/m~3,温度120℃,原煤水分为5%时,在计算流速时如果用纯空气的重度,则动压头需乘以 First, the foreword In the boiler operation adjustment test, often meets the need to carry on the dusty air current velocity, the density and so on the measurement. Especially in recent years, direct blowing powder milling system increased year by year, the problem is even more prominent. In the case of a psoriasis tube or a psoriasis tube, the flow rate of dust is measured and the flow rate is calculated using the formula W = 4.43 (H / γ) ~ (1/2) Heavy γ into the above formula, then the above dynamic head H in the direct measurement of the data, whether it needs to be amended and how to correct, in other words, if the above equation is used in the measured dynamic pressure head H, the degree of γ is based on γ_ (?) Of pure air or γ (_ ((?) + .n)) of dust-containing gas flow, or a certain number between the two. Regarding this problem, In the magazine have been reported, but the views are inconsistent, such as the introduction of information, in a horizontal section of the test bed specifically for dust concentration, velocity, particle size of the test results of the pint tube, according to the test results, the author When calculating the flow rate, the head H is the reading of the pelt tube, the heavy γ is the heavy mixture of the dust-laden gas stream. The data mentioned that when the pulverized coal volume concentration is 500kg / m ~ 3, the temperature is 120 ℃ and the raw water is 5 %, When using the pure air when calculating the flow velocity of the heavy, the dynamic head to be multiplied by