Superfluid Helium Evolution Phenomena (SHeEP)

research area: fluid dynamics

experiment title:

Superfluid Helium Evolution Phenomena

experiment acronym: SHeEP

funding agency: ESA

grant number: CORA - Program

performing organization:

Faculty of Mechanical and Power Engineering, Wrocław University of Technology, Poland

prime investigator:

Prof. Sławomir Paweł Pietrowicz

experiment objective

abstract

The proposed research is concerned with the thermal-flow phenomena occurring in superfluid helium-4 in the vicinity of the λ transition. In spite of what is generally considered to be an accurate description of this remarkable liquid, which is the two-fluid approach developed by Landau and Khalatnikov, an alternative modelling technique has been proposed. It is based on the Extended Irreversible Thermodynamics theory, thus breaking with the assumption of two mutually interpenetrating phases, characteristic for the said model. Instead of considering velocities of individual phases, one obtains a macroscopic description based on barycentric velocity of the fluid and heat flux density as dependent variables, which is convenient from an empirical point of view. Furthermore, this approach has been proven to be consistent with the classic one. In the above framework the λ transition may be depicted using the order parameter as an additional dependent variable for which a separate evolution equation is provided. This description seems alluring, bearing in mind that second order phase transitions arise from symmetry breaking. The main goal of this research is to validate the accuracy of the mono-fluid approach in view of the dynamics of the λ transition.

related publications

  • S. Takada, N. Kimura, M. Mamiya, T. Okamura, M. Nozawa, M. Murakami, Visualization study of bubble generation and collapse in He II under microgravity condition, AIP Conference Proceedings 1573, 292-299, 2014
  • S. Takada, N. Kimura, M. Mamiya, T. Okamura, M. Nozawa, M. Murakami, Visualization and temperature measurement during vapor bubble growth in He II film boiling under microgravity condition, Proceedings of 24th International Cryogenic Engineering Conference edited by K. Funaki, et al, IOP publishing, Tokyo, Japan, 119-122, 2013
  • N. Kimura, S. Takada, S. Gotoh, H. Kawamata, M. Iida, M. Murakami, H. Nagai, M. Mamiya, Development of a Small He II Cryostat with Optical Windows for a Microgravity Experiment, Cryogenics 51, 74-78, 2011
  • S. Takada, M. Murakami, N. Kimura, H. Kobayashi, Visualization study of the interface between superheated He II and superheated He I in a two-dimensional narrow channel by using the shadowgraph method, Cryogenics 49, 576-582, 2009

experiment campaigns

experiment year: 2016
number of drops: 32

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