층류 동축류 제트 부상화염에서 부력에 의한 자기진동과 루이스 수에 의한 자기진동 비교에 관한 실험적 연구
Experimental Study on Comparison between Buoyancy Driven and Lewis Number Induced Self-excitations in Laminar Lifted Coflow-jet Flames
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Experimental study in laminar propane coflow jet flames has been conducted to investigate self-excitations. For various propane mole fractions and jet velocities, two types of self-excitation were observed: (1) buoyancydrivenself-excitation (hereafter called BDSE) and (2) Lewis-number-induced self-excitation coupled with (1)(hereafter called LCB). The mechanism of Lewis-number-induced self-excitation (hereafter called LISE) isproposed. When the system Damköhler number was lowered, LISE was shown to be launched. The LISE isclosely related to heat loss, such that it can be launched in even helium-diluted methane coflow-jet flame (Lewisnumber less than unity). Particularly, The LISE becomes significant as the Damköhler number decreases andheat-loss is excessively large.
Abstract
Experimental study in laminar propane coflow jet flames has been conducted to investigate self-excitations. For various propane mole fractions and jet velocities, two types of self-excitation were observed: (1) buoyancydrivenself-excitation (hereafter called BDSE) and (2) Lewis-number-induced self-excitation coupled with (1)(hereafter called LCB). The mechanism of Lewis-number-induced self-excitation (hereafter called LISE) isproposed. When the system Damköhler number was lowered, LISE was shown to be launched. The LISE isclosely related to heat loss, such that it can be launched in even helium-diluted methane coflow-jet flame (Lewisnumber less than unity). Particularly, The LISE becomes significant as the Damköhler number decreases andheat-loss is excessively large.
참고문헌 (14)
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