Primary air ratio change and gas interchangeability index correct for domestic gas cooker burning multi-source natural gases

In this paper, the influences of burner head temperature and gas properties on primary air ratio change of domestic gas cooker were studied, when natural gases interchange. Then though experimental test, the equation of AGA Lifting Index was modified and its interchangeability limits for Chinese natural gas interchangeability prediction was redefined. From results, when natural gases interchange, the original calculation equation of primary air ratio change should be corrected by temperature. The temperature correction coefficient m values1.1, when poor gas substitutes rich gas. As well as m values 0.9 when rich gas substitutes poor gas. And m values 1.0 when similar quality gases interchange. No flash-back and yellow tip were observed for all 17 domestic gas cookers under 11 test natural gases. Unfortunately, there were about half substitute natural gases appearing lifting, but all these gases were in the limit of AGA Lifting Index. Hence it verified that AGA Lifting Index IL can't be totally suitable when it's used to predict Lifting for Chinese natural gas interchangeability. According to natural gas interchangeability experiment on Chinese domestic gas cookers, it corrected the interchangeable limit of AGA Lifting Index IL as follows: total interchangeable, IL ≤ 1.09; interchangeable, 1.09＜IL＜1.13; un-interchangeable, IL ≥ 1.13.