In this bachelor's thesis, we designed the boiling chamber of a micropropulsion engine as part of the propulsion system for CubeSat satellites. The first part of the thesis is devoted to a review of the theoretical basis of thrust in aerospace engineering and the literature in the field of micropropulsion technology for manoeuvring small satellites. We then focus on a selected part of this technology, i.e. vaporizing liquid microthrusters (VLM), and the associated instabilities in the boiling process that have a negative impact on the vaporation process. Additive technologies (3D printing) have been chosen to fabricate the boiling chamber of the microthruster, which have drastically changed the development processes in the field of microfluidics. The limitations of the chosen technology in terms of accuracy, temperature stability and fusion capability were tested, followed by the design of the geometry of the boiling chamber and the establishment of a measurement test site to visualise the vaporisation process in the boiling chamber. Several boiling chamber designs were iteratively developed and tested, with a focus on the control of the vapour backflow and the arrangement of the microfins. During the experimental validation, we captured images with a high-speed camera and analysed them with appropriate software, focusing on the locations of vapour bubble formation and travel. During the operation of the boiling chamber, we detected the expected boiling instability problems and confirmed the hypothesis that the geometry of the microfins and the geometry of the inlet channel of the boiling chamber is of key importance for preventing instabilities during the microthrusters operation.
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