NASA’s Quantum Leap in Combustion Research: The HPTC Apparatus
The NASA Scientific and Technical Information Program has taken a significant leap forward in its quest to explore combustion phenomena in high-pressure, trans-critical (HPTC) environments. Thanks to the development of a cutting-edge apparatus, NASA researchers are now equipped to delve into the intricate world of liquid droplet combustion like never before. This apparatus is poised to revolutionize our understanding of combustion processes, particularly auto-ignition, across a spectrum of fuel types and ambient conditions.
NASA Fuel Combustion Test Images Acquired by Mikrotron CoaXPress Camera
Central to this groundbreaking development is a specially designed pressure vessel meticulously carved from a single block of aluminum. Within this vessel, HPTC experiments come to life. Researchers can meticulously manipulate variables such as pressure, temperature, and oxygen content to simulate various conditions, all while scrutinizing the ignition and burning of minuscule fuel droplets. Each experiment is brief, typically lasting only ten seconds, with fuel droplets measuring a mere 1mm in diameter.
To capture these fleeting moments of combustion, a sophisticated array of cameras has been strategically positioned. Two cameras, stationed orthogonally outside the upper portion of the chamber, work in tandem to document the combustion events. One, a Mikrotron MC4082 four-megapixel monochrome camera, boasts a remarkable frame rate of 1,000 frames per second with a resolution of 960×960 pixels. It captures the droplet as a shadowgraph, employing fixed settings of 80 dB gain, 570 μs exposure, and a black level of 0. An LED backlight, synchronized to the Mikrotron camera, provides illumination at a wavelength of 525 nm.
Simultaneously, a USB3 HD color video camera records the flames at 180 fps, offering a resolution of 1024×1024 pixels. This camera provides variable gain and exposure settings for optimal flame capture during the experiments. An Allied Vision Prosilica GT 1290 Gigabit Ethernet HD monochrome camera is also part of the setup, delivering a shadowgraph view of droplet deployment before ignition. This camera operates at 30 fps, with a resolution of 960×960 pixels, automatic gain adjustment, and a 25 ms exposure.
The wealth of data collected by these cameras is efficiently processed and stored on a local PC running NorPix StreamPix digital video recording software. The images are saved in an 8-bit .seq format, a proprietary NorPix format that can be readily converted to audio video interleave (.avi) or tagged image file format (.tiff) files for further analysis.
What’s truly exciting about this innovation is that it opens the door for NASA researchers to conduct normal-gravity liquid droplet combustion experiments without the need for Zero Gravity test equipment. Moreover, there’s a tantalizing prospect on the horizon – the potential development of a similar capability for conducting high-pressure combustion and supercritical oxidation research aboard the International Space Station.
In summary, this apparatus represents a significant advancement in combustion research, offering scientists a remarkable tool to probe the mysteries of combustion in HPTC environments. With the help of state-of-the-art cameras, data collection systems, and an innovative pressure vessel, NASA is set to unlock new insights into the fundamental processes that drive combustion, paving the way for safer and more efficient combustion technologies both on Earth and in space.
About Mikrotron, a brand of SVS-Vistek GmbH:
As of January 1, 2022, Mikrotron became a part of SVS-Vistek GmbH. This integration marks a powerful synergy in the world of high-speed cameras, combining the strengths and expertise of both companies under the umbrella of TKH Vision. Mikrotron, now operating as a brand of SVS-Vistek, has earned international recognition for its small yet robust high-speed cameras in the industrial image processing sector. These digital high-speed cameras are revered for their exceptional technical performance and find applications in a myriad of industries, from industrial and scientific research to sports, advertising, and nature filmmaking.
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