Dr Yarjan Samad talks about what he's working on for the loop heat pipes, and why he's excited about the parabolic flight!
I am very excited to be working on this parabolic flight campaign to improve the performance of loop heat pipes. This fits very well with my research interests in the broad topic of functional foams and coatings based on graphene and layered materials. My research on these focuses on applications in aerospace, health, environment and energy applications.
In this project, my task is to modify the porosity of the porous metal used as the heat-exchange medium – known as the wick – in the loop heat pipe. At the Cambridge Graphene Centre, we deposit graphene-based inks in the wicks to develop architectures inside the pores of the metal. The smaller pores increase the capillary pressure and enhance the thermal power.
We have developed several batches of samples of coated wicks. Once coated, the capillary pressures and thermal powers are tested by the team in Université libre Bruxelles, Belgium.
We have obtained very promising results from the methods we are using to modify the wicks. Our current task is to optimise the coating methods further, varying parameters such as the concentration of the graphene based ink and reduction temperatures. The conditions that result in best capillary pressures and thermal power in ground conditions will then be selected to be tested in the parabolic flight in November
By modifying the wicks, the aim is to create a loop heat pipe that functions without any human interaction for decades. This would be ideal for space applications, where satellites must function continuously without maintenance. In addition to space, these loop heat pipes will also be promising for ground based applications such as transport. In the next steps of this project, I expect that it could be possible to completely replace the metallic structure with graphene and create an all-graphene porous wick that functions better, is easy to manufacture and is long lasting.
While my bigger interest lies in developing metallic wicks with much better properties than the state of the art, the opportunity to perform research in micro-gravity conditions on a parabolic flight makes the entire experience more thrilling and exciting. I am really excited to go on the parabolic flight in November so that we can validate our current promising results in space conditions and plan the future directions for this project.
16 August 2017 14:35