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ISSN Online: 2379-1748

7th Thermal and Fluids Engineering Conference (TFEC)
SJR: 0.152 SNIP: 0.14 CiteScore™:: 0.5

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Clarivate CPCI (Proceedings) Scopus
May, 15-18, 2022 , Las Vegas, NV, USA

FROST DEPOSITION IN TURBULENT FLOW OVER A COLD PLATE USING DIRECT NUMERICAL SIMULATION

Get access (open in a dialog) pages 667-670
DOI: 10.1615/TFEC2022.mpp.040931

Resumo

Using direct numerical simulation (DNS), a three-dimensional time- and space-dependent model has been introduced to predict frost buildup in turbulent flow accounting for both the air and frost layers. The air layer is fully resolved through computing the velocity, temperature, and vapor mass fraction fields, while the frost layer evolves due to mass and heat transfer. The immersed boundary method is implemented to dynamically couple complex non-linear interactions between heat and mass transfer at the evolving boundary. To make these simulations possible, a few computational challenges had to be ovecome. First, a source term has been added to the energy and transport equations to ensure zero gradients for the far-field conditions and to maintain a prescribed mean temperature and humidity for the free steam. Second, a constant mean flow thickness and a level of turbulence intensity in the numerical domain require that the mean frost thickness be subtracted after each time step. Third, a new time acceleration method has been introduced to account for the large disparity in time scales between the slow evolving frost layer and the fast-evolving turbulent flow field. A frost densification scheme has also been employed to control the frost properties in the direction normal to the plate. The numerical model has been validated with experimental data by comparing frost thickness and its growth rate in the laminar regime.