Preliminary Investigation of Three-Dimensional Flame Measurements with a Plenoptic Camera

Abstract

Light field imaging with a plenoptic camera offers a straightforward method for capturing three-dimensional information about a flow with a single camera. Chemically reacting flows are a subject of great interest in the aerospace industry; however, there is little research regarding the imaging of combustion processes or flames with a plenoptic camera. A preliminary investigation into the viability of three-dimensional flame measurements with a plenoptic camera is conducted. A high-level overview of the key concepts undergirding the plenoptic camera is given. Three-dimensional deconvolution is described as a promising volume reconstruction technique. Some initial results are presented. Preliminary conclusions are shared with a brief discussion of the direction of future work. NomenclatureFlow Diagnostics Laboratory ALFA = Auburn Light Field Analyzer FOV = field of view GIF = Graphics Interchange Format LIDAR = light detection and ranging LIF = laser induced fluorescence LFI = light field imaging LFM = light field microscopy MART = multiplicative algebraic reconstruction technique mm = millimeters PIV = particle image velocimetry PNG = Portable Network Graphics PSF = point spread function = image distance = new image distance TIFF = Tagged Image File Format = refocusing factor

Investigation and optimization of sampling characteristics of light field camera for flame temperature measurement

“…[10][11][12] In recent years, the light field camera is applied in combustion to investigate the flame radiation information and reconstruct the 3-D temperature distribution. [13][14][15][16][17][18][19][20][21] For example, Sun et al [13] proposed a novel algorithm to reconstruct the 3-D temperature distribution of ethylene-air diffusion flames based on the radiative transfer equation and Planck's radiation law, where a commercial focused light field camera (Raytrix R29) was used to sample the flame radiative information. Niu et al [16,17] developed an algorithm to reconstruct the temperature and the radiative properties of a rotationally symmetrical flame using the light field camera.…”

“…Niu et al [16,17] developed an algorithm to reconstruct the temperature and the radiative properties of a rotationally symmetrical flame using the light field camera. Jeffrey et al [18] also proposed a light field camera system to measure the flame cross-sectional radiative intensity based on a vertical view of the camera and a deconvolution method. Above studies illustrates the practicality of the light field camera for the flame temperature measurement.…”

Integral Photography Technique for Three-Dimensional Imaging of Dusty Plasmas

“…Combined with intrinsic fluorescence spectroscopy [33], specification of dust's materials will be available not only for standard polymer but also for unusual target such as microorganisms [34,35]. Moreover, deconvolution techniques [36,37] will extend the integral photography to determine 3D distribution of spatially continuous light sources [38]. 3D information of bremsstrahlung emissivity distribution should be obtained Table 2.…”

Advanced Laser-Based Techniques for Gas-Phase Diagnostics in Combustion and Aerospace Engineering

“…The third method is using new sensors combined with numerical techniques to produce instantaneous measurements with better-defined spatial resolution. One example is using a plenoptic camera 239 which implements an array of micro-lenses in front of the sensor that capture both the intensity and the direction for light rays simultaneously. Comparing with tomographic methods, the plenoptic camera approach reduces the complexity of the measurement system and can also accommodate limited optical access.…”