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arXiv · 2509.14442

Indoor Airflow Imaging Using Physics-Informed Background-Oriented Schlieren Tomography

Arjun Teh·Wael H. Ali·Joshua Rapp·Hassan Mansour
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Abstract

We develop a framework for non-invasive volumetric indoor airflow estimation from a single viewpoint using background-oriented schlieren (BOS) measurements and physics-informed reconstruction. Our framework utilizes a light projector that projects a pattern onto a target back-wall and a camera that observes small distortions in the light pattern. While the single-view BOS tomography problem is severely ill-posed, our proposed framework addresses this using: (1) improved ray tracing, (2) a physics-based light rendering approach and loss formulation, and (3) a physics-based regularization using a physics-informed neural network (PINN) to ensure that the reconstructed airflow is consistent with the governing equations for buoyancy-driven flows.

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Arjun Teh, Wael H. Ali, Joshua Rapp, Hassan Mansour. 2025-09-17. Indoor Airflow Imaging Using Physics-Informed Background-Oriented Schlieren Tomography. https://arxiv.org/abs/2509.14442

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