| 摘要 |
PCT No. PCT/SE85/00537 Sec. 371 Date Oct. 16, 1986 Sec. 102(e) Date Oct. 16, 1986 PCT Filed Dec. 20, 1985 PCT Pub. No. WO86/03834 PCT Pub. Date Jul. 3, 1986.A method of measuring the volume (V) of a gas in a container (20) comprises varying the container volume according to a sine wave between a minimum and a maximum value, the variation being made at a constant frequency but at varying amplitude, to obtain a predetermined pressure difference ( DELTA p), and the volume difference ( DELTA V) corresponding to said predetermined pressure difference ( DELTA p) being determined by detecting the points of time when at least two points on the sine wave are attained which correspond to two predetermined values of the container volume. By measuring the time between the two points on the sine wave, the sine wave peak values for the volume difference ( DELTA V) corresponding to said predetermined pressure difference ( DELTA p) may be calculated and, thus, the said volume difference ( DELTA V). By means of the formula V= DELTA Vxp0x eta / DELTA p, wherein p0=the static pressure and eta =Cp/Cv wherein Cp an Cv are the specific heat capacity at, respectively, constant pressure and constant volume for the gas within the container, the gas volume (V) in the container may then be determined. An apparatus for carrying the method into effect has also been constructed. |
