ETD

• custom parameter code validation.
• Infrared images post-processing
• Microgravity
• Pulsating Heat Pipe

The Thermal Control Subsystem (TCS) has always played a key role in spacecraft design. Its primary objective is to maintain all spacecraft, payload and subsystems within their required temperature constraint during each mission phase. Moreover, the continuous miniaturization of electronic components along with the complexity rising of mission re- quirements are pushing towards the research of new solutions.
An emerging technology, the Pulsating or oscillating Heat Pipes (PHP), is one of the cheapest and most reliable thermal management systems. For these reasons is one of the most promising not only for space applications but also for civil ones. However, since the phenomena that govern its functioning are not well understood, its large scale adoption is still far from being reality. In the last two decades many significant efforts have been done to develop numerical models of such devices, but just few of them are able to perform a complete thermo-hydraulic simulation. One of the most sophisticated models present in literature is the one developed by V. Nikolayev, which reproduced many physical phe- nomena observed in PHPs. Nevertheless, it has not been validated yet due to the lack of experimental data.
This thesis represents a first step towards a complete validation of Nikolayev’s model using experimental data provided by the University of Pisa. First, an experimental data post-processing has been performed to obtain all the relevant quantities for the valida- tion. Then, a model update was developed in order to represent as closely as possible the real device with all its features. Startup simulation results, carried out on multiple parameters, show a remarkable agreement from both qualitative and quantitative point of view. This could not be possible without a good description of all the interactions between dominant phenomena governing PHP operations.