The Use of Air Staging to Reduce the NO<sub>x</sub>Emissions from Coal Burning Rijke Pulse Combustors

Miller, N.; Powell, E. A.; Chen, F.; Zinn, B. T.

doi:10.1080/00102209308935321

Cited by 11 publications

(5 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thermo-acoustic systems have been exploited in the past to perform beneficial functions in a number of industrial applications. Examples include: promoting higher combustion efficiency, [10][11][12] fuel savings, 13,14 controlled waste incineration, 15 slurry atomization, 16 reduced pollutant formation, [17][18][19][20][21][22][23][24][25][26] increased fuel residence time in combustion chambers, [27][28][29] increased convective heat transfer rates, 30 and lower operating and equipment costs. 13,31,32 The basic mechanisms that trigger the beneficial consequences are invariably associated with controlling the acoustic field 31 in order to improve mixing 33 and/or heat transfer.…”

Section: Introductionmentioning

confidence: 99%

“…13,31,32 The basic mechanisms that trigger the beneficial consequences are invariably associated with controlling the acoustic field 31 in order to improve mixing 33 and/or heat transfer. 14,[34][35][36][37] One of the archetypal applications of thermoacoustics arises in the operation of coal-fired furnaces 14,20,28,31 and gas turbines. 6,35,38 In addition to its function in improving combustion efficiency, a pulsating pressure field is used to increase the size of exhaust particles.…”

Section: Introductionmentioning

confidence: 99%

“…In trying to circumvent this deficiency, it has been demonstrated that acoustic energy is capable of promoting the agglomeration of fine ash particles entrained in high temperature gas streams. 11,12,[17][18][19][20][21]24,26,29,39 As the name suggests, acoustic agglomeration is a process in which high intensity sound is used to assemble micron and submicron sized particles in aerosols. The effect of sound is to cause relative motions between particles and increase their collision rate.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The Rijke tube revisited via laboratory and numerical experiments

Majdalani

2001

35th AIAA Thermophysics Conference

View full text Add to dashboard Cite

In this paper, results proceeding from experimental studies and numerical simulations of the time-dependent flowfield inside a Rijke tube are presented and interpreted. A discussion is carried out based on existing speculations and standard scaling concepts. The main results include a similarity parameter that appears to play an important role in the heat driven oscillations. This parameter relates heat perturbations to velocity, pressure, and the square of a characteristic length. A hypothesis that relates heat oscillations to the compounded effects of pressure and velocity oscillations is discussed. This is done via computational, experimental, and scaling considerations. Since previous analytical theories have linked heat oscillations to either velocity or pressure coupling, the current analytical model agrees with and reconciles between both schools of thought. In compliance with the Rayleigh criterion, it is found that the heat source must be positioned at a critical distance of quarter length from the tube's entrance for resonance to occur. At that location, the modular product of acoustic velocity and pressure, known as the energy-flux vector modulus, is maximized. This observation confirms our proposed interpretation since the critical point where thermoacoustic coupling is maximized corresponds to the same spatial location where the modulus of acoustic intensity is largest. Furthermore, both numerical and laboratory experiments suggest that pressure oscillations inside the Rijke tube grow commensurately with increasing heat input. With a sufficiently small heat input, the acoustic sinks exceed the sources and acoustic attenuation takes place. In that case, no appreciable sound can be generated. Conversely, when the heat input is augmented beyond a critical threshold, acoustic sinks become insufficient, and rapid acoustic amplification ensues. The experiment also indicates the importance of the air's mean flow convection currents in the coupling mechanism. It is found that unless the air's mean flowrate is appreciable, no acoustic amplification can exist. To demonstrate the vitality of air currents, a strong mean flow is induced artificially by means of an exhaust fan. At the outset, acoustic growth is reported in both vertical and horizontal tube orientations. It is concluded that forced air currents can compensate for the lack of buoyancy in the horizontal tube configuration.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The Rijke tube revisited via laboratory and numerical experiments

Majdalani

2001

35th AIAA Thermophysics Conference

View full text Add to dashboard Cite

show abstract

“…This is primarily motivated by their potential applications in the environmental/coastal, biological, medical/health and industrial sectors [1]. Within this last category, where reciprocating flows play a predominant role, we can highlight applications such as oil well drilling [2], heat exchangers in Stirling motors, pulse-tube cryocoolers and gas turbines [3][4][5]. On the other hand, among the most notable advances in the medical/health field include artificial hearts and ventricular assist devices whose design involves the utilization of different types of pumps (diaphragm, pusher-plate, peristaltic, centrifugal and axial flow) to produce pulsatile blood flow [6,7].…”

Section: Introductionmentioning

confidence: 99%

“…the area A of the mouthpiece. d) Two opening positions of the mobile claw to indicate the area A1 (shown in purple color), as well as the internal volume of the socket, the latter corresponding to the intermediate position (3). Clearly, the volume of the socket changes with the theta angle and also with time.…”

mentioning

confidence: 99%

Accelerated corrosion of low carbon steel by oscillatory acidic streams generated with a bio-inspired claw device

Godínez,

Montoya-Rangel,

Montoya

2024

PLoS ONE

View full text Add to dashboard Cite

A mechanical device inspired by the pistol shrimp snapper claw was developed. This technology features a claw characterized by a periodic opening/closing motion, at a controlled frequency, capable of producing oscillating flows at transitional Reynolds numbers. An innovative method was also proposed for determining the corrosion rate of carbon steel samples under oscillating acidic streams (aqueous solution of HCl). By employing very-thin carbon steel specimens (25 μm thickness), with one side coated with Zn and not exposed to the stream, it became possible to electrochemically sense the Zn surface once the steel sample was perforated, thus providing the average dissolution rate into the most relevant pit on the steel surface. Furthermore, a laser light positioned beneath the metallic sample, along with a camera programmed to periodically capture images of the steel surface, facilitated the accurate counting of the number of newly formed pits. The system consisting of the thin steel sample and the Zn coating can be seen as a type of corrosion sensor. Furthermore, the proposed laser illumination method allows corroborating the electrochemical detection of pits and also establishing their location. The techniques crafted in this study pave the way for developing alternative corrosion sensors that boast appealing attributes: affordability, compactness, and acceptable accuracy to detect in time and space localized damage.

show abstract

An experimental study on the impact of acoustics and spray quality on the emissions of CO and NO from an ethanol spray flame

McQuay

Dubey

Nazeer

1998

Fuel

View full text Add to dashboard Cite

The Use of Air Staging to Reduce the NO_xEmissions from Coal Burning Rijke Pulse Combustors

Cited by 11 publications

References 2 publications

The Rijke tube revisited via laboratory and numerical experiments

The Rijke tube revisited via laboratory and numerical experiments

Accelerated corrosion of low carbon steel by oscillatory acidic streams generated with a bio-inspired claw device

An experimental study on the impact of acoustics and spray quality on the emissions of CO and NO from an ethanol spray flame

Contact Info

Product

Resources

About

The Use of Air Staging to Reduce the NOxEmissions from Coal Burning Rijke Pulse Combustors

Cited by 11 publications

References 2 publications

The Rijke tube revisited via laboratory and numerical experiments

The Rijke tube revisited via laboratory and numerical experiments

Accelerated corrosion of low carbon steel by oscillatory acidic streams generated with a bio-inspired claw device

An experimental study on the impact of acoustics and spray quality on the emissions of CO and NO from an ethanol spray flame

Contact Info

Product

Resources

About

The Use of Air Staging to Reduce the NO_xEmissions from Coal Burning Rijke Pulse Combustors