| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method and a system for measuring calories of liquefied natural gas for improving measurement accuracy of a gas calorific value of the liquefied natural gas. <P>SOLUTION: A method and a system for measuring calories of liquefied natural gas are constituted so that density operation means 13 calculates liquid density D<SB POS="POST">x</SB>of liquefied natural gas to be measured by the following liquid density derivation function from liquid density D<SB POS="POST">w</SB>, reference temperature T<SB POS="POST">w</SB>, and characteristic frequency relevant information F<SB POS="POST">w</SB>of first reference fluid, liquid density D<SB POS="POST">a</SB>, reference temperature T<SB POS="POST">a</SB>, and characteristic frequency relevant information F<SB POS="POST">a</SB>of second reference fluid, temperature T<SB POS="POST">x</SB>and characteristic frequency relevant information F<SB POS="POST">x</SB>of the liquefied natural gas to be measured, and a coefficientαon the basis of storage information of density operation information storage means 11, measurement information of temperature measurement means 7, and detection information of frequency relevant information detection means, and the coefficientαis set to a numeric value according to the temperature T<SB POS="POST">x</SB>of the liquefied natural gas to be measured. D<SB POS="POST">x</SB>=f[D<SB POS="POST">w</SB>,D<SB POS="POST">a</SB>,F<SB POS="POST">x</SB><SP POS="POST">2</SP>×(1-α×T<SB POS="POST">x</SB>),F<SB POS="POST">a</SB><SP POS="POST">2</SP>×(1-α×T<SB POS="POST">a</SB>),F<SB POS="POST">w</SB><SP POS="POST">2</SP>×(1-α×T<SB POS="POST">w</SB>)]. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
