OCR Text |
Show 1 1 4-2-1 Steady S ta te Aspect (1) rIeat efficiency and fuel consumption Comparing wi th the evaporation combustion for 2 --2.5 excess air ratio, th~ foam combustion achieves complete combustion even at low excess air ratio. Low excess air resul t high exhaust gas temperatur~ and it increases the effectiveness of the radiation coefficient. In other ward, the foam combustion can decrease fuel consumptioQ (2) C 0 genera t i on As mix'ing of the vaporized fuel and air is accelated, COgeneration decreases as well as the spray combustioQ (3) N Ox genera t ion It is known that NOx formation is storongly dependent on temperature, and local super-hea t causes the format i on of N Ox . And as the burner is divided pre-mix zone and main combustion zone by burner ring, the foam combustion burner achieves nearly complete combustioQ Because of the homogeneous phase burning and complete combustion, the foam combustion reduces ~Ox generation as well as the evaporation combustioQ (Coefficient of Radiation) = (Radiated H.e.2t)/(Fuel Value) ~ 5 0 ....., c 0 4 0 ~ "C c:: 3 0 '0 -0 2 0 c:: G) --() 1 0 ~ 8 0 0 Foam Corbustlon (excess air ratio: 1.4-2.0) ___ :-----, ----- Ev~rat1on CcxrDustion (excess air ratio: 2.0-2.5) 2 .. - Fuel Consumpt,i on ( t /h) 3 Fig. 11 Heat efficiency and . f~el consumptIon ~ -o u "o u ,. o z O. 1 ___ --,....----r----, "- 0.05 /"--- .. Ev"'''''''ration Carbust~ ... ""r" . '"'" Spray Coabustion \ Fj Conbustion oL---~--~---~ 2 3 Fuel Consumpti on ( t /h) Fig. 12 COgeneration 5 0 ~ - o 2 3 Fuel Consumpti on ( t /h) Fig. 13 NOx generation |