| 摘要 |
<p>A method of measuring a gas mass fraction (X) in a mass of liquid and gas flowing in direction (A) along pipeline (2) which includes a venturi formed by throat (10), convergent portion (12) and divergent portion (14). Adjacent the venturi (12, 10, 14) but upstream is a flow conditioner (28) creating a uniform mixture of gas and liquid downstream so as to reduce or avoid slip between the gas and liquid phases in the venturi. Differential pressure (DP1) is measured between a position upstream of the flow conditioner and a position intermediate the flow conditioner and venturi. Differential pressure (DP2) is measured between the throat and a position intermediate the flow conditioner and venturi. Differential pressure (DP3) is measured across the venturi. Computer (50) calculates the gas mass fraction (X) using a formula that may take the form: X = a.(DP1)?b.(DP2)c.(DP3)d¿.(DP2-DP3)e.(DP1+DP3)f, in which a, b, c, d, e and f are constants.</p> |
