Characteristics of lifted flames in nonpremixed turbulent confined jets

被引：58

作者：

Cha, MS ^{[1
]}

Chung, SH ^{[1
]}

机构：

[1] Seoul Natl Univ, Dept Mech Engn, Seoul 151742, South Korea

来源：

TWENTY-SIXTH SYMPOSIUM (INTERNATIONAL) ON COMBUSTION, VOLS 1 AND 2 | 1996年

关键词：

D O I：

10.1016/S0082-0784(96)80208-6

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

Characteristics of lifted flames in nonpremixed jets were studied experimentally with emphasis on the effects of the entrained flow field which was varied by placing a plate near the nozzle and by confining the jet. Results show that lifted flame behavior in a confined jet is drastically different: from that of a free jet. In the confined jet, the liftoff height is linearly proportional to the nozzle diameter and the flow velocity, while the liftoff height is independent of the nozzle diameter in the free jet. The ratio of the liftoff height at blowout to the nozzle diameter maintains a near-constant Value of 50 for both the free and confined jets. The blowout velocity is linearly proportional to the nozzle diameter in the free jet, whereas it is independent of the nozzle diameter in the confined jet. The jet Velocity at liftoff maintains a near-constant value for the free jet, while the liftoff velocity decreases with the increase in the nozzle diameter for the confined jet. The blockage effect of the plate near the non;le exit systematically reduces the liftoff height and a criterion is proposed to include such an effect in interpreting liftoff behavior.

引用

页码：121 / 128

页数：8

共 20 条

[1]

Becker HA, 1963, P COMBUST INST, V9, P7

[2]

Broadwell J.E., 1984, PROC COMBUST INSTIT, V20, P303, DOI [10.1016/S0082-0784(85)80515-4, DOI 10.1016/S0082-0784(85)80515-4]

[3]

CHEN YC, 1996, UNPUB COMBUST FLAME

[4] ON THE CHARACTERISTICS OF LAMINAR LIFTED FLAMES IN A NONPREMIXED JET [J].

CHUNG, SH ;

LEE, BJ .

COMBUSTION AND FLAME, 1991, 86 (1-2) :62-72

[5]

DAHM WJA, 1988, 22ND S INT COMB, P801

[6] Lift-off Heights and Visible Lengths of Vertical Turbulent Jet Diffusion Flames in Still Air [J].

Kalghatgi, Gautam T. .

COMBUSTION SCIENCE AND TECHNOLOGY, 1984, 41 (1-2) :17-29

[7] BLOW-OUT STABILITY OF GASEOUS JET DIFFUSION FLAMES .1. INSTILL AIR [J].

KALGHATGI, GT .

COMBUSTION SCIENCE AND TECHNOLOGY, 1981, 26 (5-6) :233-239

[8]

LEE BJ, 1994, 25 S INT COMB COMB I, P1175

[9]

LEE BJ, 1996, IN PRESS COMBUST FLA

[10]

Miake-Lye R.C., 1988, P COMBUST INST, V22, P817, DOI DOI 10.1016/S0082-0784(89)80091-8

← 1 2 →