TY - JOUR
T1 - Experimental investigation on heat loss and combustion in methane/oxygen micro-tube combustor
AU - Li, Junwei
AU - Zhong, Beijing
PY - 2008/5
Y1 - 2008/5
N2 - To understand working features of a micro-tube combustor, combustion of CH4/O2 was carried out in three types of micro-tubes with the same outer diameter of 3 mm. In the tests, combustion characteristics and heat loss in micro-tubes were studied. It is shown that when equivalence ratio was lower than unity, CH4 was not completely oxidized and a great amount of gas H2 and CO was produced, which lowered the combustion heat release. If equivalence ratio is a little larger than unity, CH4 was completely oxidized to gas CO2 and water vapor, and the reaction released the maximum combustion heat. Meanwhile, heat loss of the tube wall was the largest. Heat loss of the stainless steel tube occupied 22% of the heat release at most. Since the wall emissivity of stainless steel tube was larger than that of ceramic tube, radiative heat loss was very large and the most occupied 70% of the total heat loss. Additionally, because thermal conductivity of ceramic was less than that of stainless steel, temperature gradient along axis was larger than that of stainless steel tube, which was disadvantageous to axis heat transfer and flame stabilization.
AB - To understand working features of a micro-tube combustor, combustion of CH4/O2 was carried out in three types of micro-tubes with the same outer diameter of 3 mm. In the tests, combustion characteristics and heat loss in micro-tubes were studied. It is shown that when equivalence ratio was lower than unity, CH4 was not completely oxidized and a great amount of gas H2 and CO was produced, which lowered the combustion heat release. If equivalence ratio is a little larger than unity, CH4 was completely oxidized to gas CO2 and water vapor, and the reaction released the maximum combustion heat. Meanwhile, heat loss of the tube wall was the largest. Heat loss of the stainless steel tube occupied 22% of the heat release at most. Since the wall emissivity of stainless steel tube was larger than that of ceramic tube, radiative heat loss was very large and the most occupied 70% of the total heat loss. Additionally, because thermal conductivity of ceramic was less than that of stainless steel, temperature gradient along axis was larger than that of stainless steel tube, which was disadvantageous to axis heat transfer and flame stabilization.
KW - Heat loss
KW - Micro-combustion
KW - Micro-combustor
UR - http://www.scopus.com/inward/record.url?scp=38849127410&partnerID=8YFLogxK
U2 - 10.1016/j.applthermaleng.2007.06.001
DO - 10.1016/j.applthermaleng.2007.06.001
M3 - Article
AN - SCOPUS:38849127410
SN - 1359-4311
VL - 28
SP - 707
EP - 716
JO - Applied Thermal Engineering
JF - Applied Thermal Engineering
IS - 7
ER -