...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Combustion and Flame >Instantaneous 3D flame imaging by background-oriented schlieren tomography
【24h】

Instantaneous 3D flame imaging by background-oriented schlieren tomography

机译：通过面向背景的Schlieren层析成像进行瞬时3D火焰成像

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We apply background-oriented schlieren (BOS) imaging with computed tomography to reconstruct the instantaneous refractive index field of a turbulent flame in 3D. In BOS tomography, a network of cameras are focused through a variable index medium (such as a flame) onto a background of patterned images. BOS data consist of pixel-wise "deflections" between a reference and distorted image, caused by variations in the refractive index along the path between the camera and background. Multiple simultaneous BOS images, each from a unique perspective, are combined with a tomography algorithm to reconstruct the refractive index distribution (or optical density) in the probe volume. This quantity identifies the edges of the wrinkled turbulent flame surface. This is the first application of BOS imaging to flame tomography, setting the stage for low-cost 3D flame thermometry. Tomography is carried out within the Bayesian framework, using Tikhonov and total variation (TV) priors. The TV prior is more compatible with the abrupt spatial variation in the refractive index field caused by the flame front. We demonstrate the suitability of TV regularization using a proof-of-concept simulation of BOS tomography on an LES phantom. The technique was then used to reconstruct the instantaneous 3D refractive index field of an unsteady natural gas/air flame from a Bunsen burner using a 23-camera setup. Our results show how BOS tomography can capture and visualize 3D features of a flame and provide benchmark data for simulations. (C) 2018 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
机译：我们应用背景X射线断层扫描（BOS）成像和计算机断层摄影技术来重建3D湍流火焰的瞬时折射率场。在BOS层析成像中，摄像机网络通过可变折射率介质（例如火焰）聚焦到图案化图像的背景上。 BOS数据由参考图像和失真图像之间的像素级“偏差”组成，这是由于沿相机和背景之间的路径的折射率变化而引起的。多个同时出现的BOS图像（分别从一个独特的角度来看）与X线断层扫描算法相结合，以重建探针体积中的折射率分布（或光密度）。该数量确定了起皱的湍流火焰表面的边缘。这是BOS成像在火焰层析成像中的首次应用，为低成本3D火焰测温奠定了基础。断层扫描是在贝叶斯框架内使用Tikhonov和总变化（TV）先验技术进行的。电视先验与由火焰前缘引起的折射率场的突然空间变化更加兼容。我们证明了使用LES幻像上的BOS断层扫描的概念验证模拟电视正则化的适用性。然后，使用23相机设置，将该技术用于从本生灯燃烧器重建不稳定天然气/空气火焰的瞬时3D折射率场。我们的结果表明BOS层析成像如何捕获和可视化火焰的3D特征并为模拟提供基准数据。 （C）2018年燃烧研究所。由Elsevier Inc.出版。保留所有权利。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号