Solid deposition in the ITER cryogenic viscous compressor

Zhang, Dongsheng; Miller, Franklin G.; Pfotenhauer, John M.

doi:10.1016/j.cryogenics.2016.05.006

Cited by 4 publications

(1 citation statement)

References 23 publications

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“…helium, hydrogen, tritium, especially at moderately low temperatures [17][18][19][20][21]. It can be important to model helium, hydrogen and tritium flows in many technological fields such as cryogenic pumps [22,23], cryogenic systems used in the huge fusion reactor ITER [24,25], monochromatic beams of helium [26,27], helium microscope [28,29], acoustic thermometry at a low temperature [30,31], experimental set-up to measure the neutrino mass [32,33], etc. In spite of the high practical interest to model gases at low temperatures, the quantum scattering has not been implemented yet in the DSMC method.…”

Section: Introductionmentioning

confidence: 99%

Modeling of transport phenomena in gases based on quantum scattering

Sharipov

2018

Physica A: Statistical Mechanics and its Applications

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A quantum interatomic scattering is implemented in the direct simulation Monte Carlo (DSMC) method applied to transport phenomena in rarefied gases. In contrast to the traditional DSMC method based on the classical scattering, the proposed implementation allows us to model flows of gases over the whole temperature range beginning from 1 K up any high temperature when no ionization happens. To illustrate the new numerical approach, two helium isotopes 3 He and 4 He were considered in two canonical problems, namely, heat transfer between two planar surfaces and planar Couette flow. To solve these problems, the ab initio potential for helium is used, but the proposed technique can be used with any intermolecular potential. The problems were solved over the temperature range from 1 K to 3000 K and for two values of the rarefaction parameter δ = 1 and 10. The former corresponds to the transitional regime and the last describes the temperature jump and velocity slip regime. No influence of the quantum effects was detected within the numerical error of 0.1 % for the temperature 300 K and higher. However, the quantum approach requires less computational effort than the classical one in this temperature range. For temperatures lower than 300 K, the influence of the quantum effects exceed the numerical error and reaches 67% at the temperature of 1 K.

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Section: Introductionmentioning

confidence: 99%

Modeling of transport phenomena in gases based on quantum scattering

Sharipov

2018

Physica A: Statistical Mechanics and its Applications

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Viscous and thermal velocity slip coefficients via the linearized Boltzmann equation with ab initio potential

Basdanis,

Valougeorgis,

Sharipov

2023

Microfluid Nanofluid

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The viscous and thermal velocity slip coefficients of various monatomic gases are computed via the linearized classical Boltzmann equation, with ab initio potential, subject to Maxwell and Cercignani–Lampis boundary conditions. Both classical and quantum interatomic interactions are considered. Comparisons with hard sphere and Lennard–Jones potentials, as well as the linearized Shakhov model are performed. The produced database is dense, covers the whole range of the accommodation coefficients and is of high accuracy. Using symbolic regression, very accurate closed form expressions of the slip coefficients, easily implemented in the future computational and experimental works, are deduced. The thermal slip coefficient depends, much more than the viscous one, on the intermolecular potential. For example, in the case of diffuse scattering, the relative differences in the viscous slip coefficient data between HS and AI potentials are less than 4%, whilst the corresponding ones in the thermal slip coefficient data are about 6% for He, reaching 15% for Xe. Quantum effects are considered for He, at temperatures 1–104 K to deduce that deviations from the classical behaviour are not important in the viscous slip coefficient, but they become important in the thermal slip coefficient, where the differences between the classical and quantum approaches reach 15% at 1 K. The computational effort of solving the linearized Boltzmann equation with ab initio and Lennard–Jones potentials is the same. Since ab initio potentials do not contain any adjustable parameters, it is recommended to use them at any temperature.

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