kHz-rate four-dimensional fluorescence tomography using an ultraviolet-tunable narrowband burst-mode optical parametric oscillator

Halls, Benjamin R.; Hsu, Paul S.; Jiang, Naibo; Legge, Ethan S.; Felver, Josef; Slipchenko, Mikhail N.; Roy, Sukesh; Meyer, Terrence R.; Gord, James R.

doi:10.1364/optica.4.000897

Cited by 69 publications

(21 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Optical emission tomography facilitates the detection of 2D or even 3D distributions of the chemiluminescence emission of laminar and turbulent hydrocarbon flames of any geometry. The development and application of tomographic methods for the reconstruction of flame structures in laminar and turbulent flames have gained a lot of interest in the past decade [1,2], for example, to image the distribution of chemiluminescent species or the volumetric OH-LIF signal [30][31][32][33], as well as the 3D flow field using tomographic particle image velocimetry (tomo PIV) [2,[34][35][36][37]. Floyd et al [6] and Anikin et al [3] were the first to investigate turbulent flames with optical emission tomography.…”

Section: Introductionmentioning

confidence: 99%

Two-Dimensional Tomographic Simultaneous Multispecies Visualization—Part II: Reconstruction Accuracy

2020

View full text Add to dashboard Cite

Recently we demonstrated the simultaneous detection of the chemiluminescence of the radicals OH* (310 nm) and CH* (430 nm), as well as the thermal radiation of soot in laminar and turbulent methane/air diffusion flames. As expected, a strong spatial and temporal coupling of OH* and CH* in laminar and moderate turbulent flames was observed. Taking advantage of this coupling, multispecies tomography enables us to quantify the reconstruction quality completely independent of any phantom studies by simply utilizing the reconstructed distribution of both species. This is especially important in turbulent flames, where it is difficult to separate measurement noise from turbulent fluctuations. It is shown that reconstruction methods based on Tikhonov regularization should be preferred over the widely used algebraic reconstruction technique (ART) and multiplicative algebraic reconstruction techniques (MART), especially for high-speed imaging or generally in the limit of low signal-to-noise ratio.

show abstract

Section: Introductionmentioning

confidence: 99%

Two-Dimensional Tomographic Simultaneous Multispecies Visualization—Part II: Reconstruction Accuracy

2020

View full text Add to dashboard Cite

show abstract

“…Thus, every camera samples both angular and spatial content (i.e., the light field). A few methods exist to capture multiple views per camera: (1) fiber optic bundles that branch from the main sensor with independent optics and mounting, effectively creating miniature cameras, have been used for optical coherence tomography [5,6] and background oriented schlieren (BOS) [7]; (2) relay prisms and mirrors in front of the primary objective produce either a stereoscope [8] or a quadscope [9], which have been demonstrated for a variety of high-speed diagnostic techniques, including tomo-PIV [10,11], LIF [9,12], and multi-color LIF [13,14]; (3) insertion of a microlens array between the primary objective and imaging sensor creates a plenoptic camera [15], which has been used for a wide variety of applications, including PIV [16][17][18][19][20], PTV [21][22][23], background-oriented schlieren [24], chemiluminescence [25], and pyrometry [25].…”

Section: Introductionmentioning

confidence: 99%

On the Impact of Subaperture Sampling for Multispectral Scalar Field Measurements

Clifford¹,

Thurow²

2020

Optics

View full text Add to dashboard Cite

The novel 3D imaging and reconstruction capabilities of plenoptic cameras are extended for use with continuous scalar fields relevant to reacting flows. This work leverages the abundance of perspective views in a plenoptic camera with the insertion of multiple filters at the aperture plane. The aperture is divided into seven regions using off-the-shelf components, enabling the simultaneous capture of up to seven different user-selected spectra with minimal detriment to reconstruction quality. Since the accuracy of reconstructed features is known to scale with the available angular information, several filter configurations are proposed to maintain the maximum parallax. Three phantoms inspired by jet plumes are simulated onto an array of plenoptic cameras and reconstructed using ASART+TV with a variety of filter configurations. Some systematic challenges related to the non-uniform distribution of views are observed and discussed. Increasing the number of simultaneously acquired spectra is shown to incur a small detriment to the accuracy of reconstruction, but the overall loss in quality is significantly less than the gain in spectral information.

show abstract

“…For example, volumetric imaging of important intermediate flame species such as OH, and PAH has been demonstrated with a repetition rate up to 10 kHz (Halls et al. 2017 b , c ). The development of VT has greatly facilitated understanding of complex combustion processes such as flame ignition and combustion instability (Ma et al.…”

Section: Introductionmentioning

confidence: 99%

Online in situ prediction of 3-D flame evolution from its history 2-D projections via deep learning

2019

View full text Add to dashboard Cite

Online in situ prediction of 3-D flame evolution has been long desired and is considered to be the Holy Grail for the combustion community. Recent advances in computational power have facilitated the development of computational fluid dynamics (CFD), which can be used to predict flame behaviours. However, the most advanced CFD techniques are still incapable of realizing online in situ prediction of practical flames due to the enormous computational costs involved. In this work, we aim to combine the state-of-the-art experimental technique (that is, time-resolved volumetric tomography) with deep learning algorithms for rapid prediction of 3-D flame evolution. Proof-of-concept experiments conducted suggest that the evolution of both a laminar diffusion flame and a typical non-premixed turbulent swirl-stabilized flame can be predicted faithfully in a time scale on the order of milliseconds, which can be further reduced by simply using a few more GPUs. We believe this is the first time that online in situ prediction of 3-D flame evolution has become feasible, and we expect this method to be extremely useful, as for most application scenarios the online in situ prediction of even the large-scale flame features are already useful for an effective flame control.

show abstract

kHz-rate four-dimensional fluorescence tomography using an ultraviolet-tunable narrowband burst-mode optical parametric oscillator

Cited by 69 publications

References 30 publications

Two-Dimensional Tomographic Simultaneous Multispecies Visualization—Part II: Reconstruction Accuracy

Two-Dimensional Tomographic Simultaneous Multispecies Visualization—Part II: Reconstruction Accuracy

On the Impact of Subaperture Sampling for Multispectral Scalar Field Measurements

Online in situ prediction of 3-D flame evolution from its history 2-D projections via deep learning

Contact Info

Product

Resources

About