Optimization of venturi-cascade enveloped burners

Conference · Thu Dec 31 04:00:00 EST 1998

OSTI ID:357758

Qubbaj, A R; Gollahalli, S R ^[1]

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1. Univ. of Oklahoma, Norman, OK (United States). School of Aerospace and Mechanical Engineering

An experimental study to control CO, NO and soot emissions of a propane diffusion flame by modifying the air infusion into the flame is presented. The modification was achieved by installing a cascade of venturis around the burning gas jet through which the air inflow was enhanced into the combustion zone. Propane jet diffusion flame at three Reynolds numbers (3600, 5100 and 6500) corresponding to burner-rim-attached, transition from attached to lifted, and fully lifted configurations were examined with different venturi sizes and spacing distributions. Temperature, CO{sub 2}, O{sub 2} and pollutant emissions (CO and NO) in the exhaust combustion products were measured before and after the modification and optimal conditions were obtained. The influence of venturi size was stronger than that of the spacing distribution. The optimal venturi diameter was between D/d = 27.5 and D/d = 3.5 which corresponded to an approximate clearance of 3 to 10 mm between the venturi throat and the burning jet (and most likely near the upper limit). The optimal configuration was the equal spacing in which the venturis were distributed equally over the flame length. The best effect of venturis was observed on the flame in transition from attached to lifted configurations. The Cascading technique at its optimal conditions compared to the baseline case of this study has shown the following: (1) visible flame length increases approximately by 18%; (2) CO{sub 2} concentration increases by 174%; and (3) CO and NO emission indices decrease by 87% and 33% respectively.

• OSTI ID: 357758
• Report Number(s): CONF-980213--
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
AIR FLOW
AIR POLLUTION ABATEMENT
CARBON MONOXIDE
COMBUSTION KINETICS
DESIGN
GAS BURNERS
NITRIC OXIDE
PROPANE
SOOT
VENTURI TUBES