Dust deflagration remains a severe safety hazard in process industries. Flame propagation velolities can be identified using high-speed cameras at sufficient frame rates. This usually leads to a trade-off in camera shutter settings so that either the dust cloud remains underexposed and is hardly visible, or the flame is too bright and saturates the camera pixels. We introduced a novel test setup using a laser light sheet to illuminate the particle cloud while, at the same time, the camera settings can be chosen in way that pixel saturation can be kept on a low level in the flame area. The recordings are done with a color high-speed camera and then processed in the YCbCr color space. Beside macroscopic values like the vertical dust cloud and flame propagation velocities we also obtain spatially resolved velocity data by using optical flow algorithms.

Electrical capacitance tomography (ECT) is a powerful tool to investigate multiphase flows in three dimensions. The sensors are extremely simple (a set of copper electrodes) and inexpensive. However, the reconstruction problem to obtain the material distribution from the capacitance measurements is ill-posed and ill-conditioned. Hence, a smart choice of reconstruction algorithm and the use of prior information is important to obtain fast and reliable data reconstruction in real-time.