Evaporation model of cluster scattering from surfaces

A dynamic film model is developed in the parallel CFD code GASFLOW-MPI for passive containment cooling system (PCCS) utilized in nuclear power plant like AP1000 and CAP1400. GASFLOW-MPI is a widely validated parallel CDF code and has been applied to containment thermal hydraulics safety analysis for different types of reactors. The essential issue for PCCS is the heat removal capability. Research shows that film evaporation contributes most to the heat removal capability for PCCS. In this study, the film evaporation model is validated with separate effect test conducted on the EFFE facility by Pisa University. The test region is a rectangle gap with 0.1m width, 2m length, and 0.6m depth. The water film flowing from the top of the gap is heated by a heating plate with constant temperature and cooled by countercurrent air flow at the same time. The test region model is built and analyzed, through which the total thermal power and evaporation rate are obtained to compare with experimental data. Numerical result shows good agreement with the experimental data. Besides, the influence of air velocity, wall temperature and gap widths are discussed in our study. Result shows that, the film evaporation has a positive correlation with air velocity, wall temperature and gap width. This study can be fundamental for our further numerical study on PCCS.

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Computational Simulation of Boil-Off Gas Formation inside Liquefied Natural Gas Tank Using Evaporation Model in ANSYS Fluent

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.393.839 ◽

2013 ◽

Vol 393 ◽

pp. 839-844 ◽

Cited By ~ 11

Author(s):

Mohamad Shukri Zakaria ◽

Kahar Osman ◽

Mohd Noor Asril Saadun ◽

Muhammad Zaidan Abdul Manaf ◽

Mohd Hafidzal Mohd Hanafi

Keyword(s):

Natural Gas ◽

Gulf Coast ◽

Current Model ◽

Computational Simulation ◽

The United States ◽

Liquefied Natural Gas ◽

Ansys Fluent ◽

Evaporation Model ◽

Gas Formation ◽

Lng Tank

Research on the waste energy and emission has been quite intensive recently. The formation, venting and flared the Boil-off gas (BOG) considered as one of the contribution to the Greenhouse Gas (GHG) emission nowadays. The current model or method appearing in the literature is unable to analyze the real behavior of the vapor inside Liquefied Natural Gas (LNG) tank and unable to accurately estimate the amount of boil-off gas formation. In this paper, evaporation model is used to estimate LNG Boil-Off rate (BOR) inside LNG tank. Using User Define Function (UDF) hooked to the software ANSYS Fluent. The application enable drag law and alternative heat transfer coefficient to be included. Three dimensional membrane type LNG cargos are simulated with selected boundary condition located in the United States Gulf Coast based on average weather conditions. The result shows that the value of BOR agrees well with the previous study done with another model and with International Marine organization (IMO) standard which is less than 0.15% weight per day. The results also enable us to visualize the LNG evaporation behaviors inside LNG tanks.

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The Intranuclear-Cascade-Evaporation Model

Computer Techniques in Radiation Transport and Dosimetry ◽

10.1007/978-1-4684-3608-2_20 ◽

1980 ◽

pp. 311-322 ◽

Cited By ~ 1

Author(s):

Tony W. Armstrong

Keyword(s):

Evaporation Model ◽

Intranuclear Cascade

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Implementation of a phenomenological evaporation model into a porous network simulation for water management in low temperature fuel cells

10.37099/mtu.dc.etds/360 ◽

2012 ◽

Author(s):

David L. Fritz

Keyword(s):

Water Management ◽

Fuel Cells ◽

Low Temperature ◽

Network Simulation ◽

Porous Network ◽

Evaporation Model ◽

Low Temperature Fuel Cells

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The Influence of Moss Colonization and Biochar Application on Evaporation Losses and Surface Crack in Shallow Carbonate–Derived Laterite During Dry–Wet Cycles

10.21203/rs.3.rs-1109021/v1 ◽

2021 ◽

Author(s):

Lulu Che ◽

Dongdong Liu ◽

Dongli She

Keyword(s):

Soil Moisture ◽

Soil Surface ◽

Soil Evaporation ◽

Interactive Effects ◽

Surface Cracks ◽

Evaporation Model ◽

Soil Desiccation ◽

Evaporation Losses ◽

Soil Moisture Conservation ◽

Surface Temperature Field

Abstract AimsSoil water deficit in karst mountain lands is becoming an issue of concern owing to porous, fissured, and soluble nature of underlying karst bedrock. It is important to identify feasible methods to facilitate soil water preservation in karst mountainous lands. This study aims to seek the possibility of combined utilization of moss colonization and biochar application to reduce evaporation losses in carbonate-derived laterite.MethodsThe treatments of the experiments at micro-lysimeter included four moss spore amounts (0, 30, 60, and 90 g·m−2) and four biochar application levels (0, 100, 400, and 700 g·m−3). The dynamics of moss coverage, characteristics of soil surface cracks and surface temperature field were identified. An empirical evaporation model considering the interactive effects of moss colonization and biochar application was proposed and assessed.ResultsMoss colonization reduced significantly the ratio of soil desiccation cracks. Relative cumulative evaporation decreased linearly with increasing moss coverage under four biochar application levels. Biochar application reduced critical moss coverage associated with inhibition of evaporation by 33.26%-44.34%. The empirical evaporation model enabled the calculation of soil evaporation losses under moss colonization and biochar application, with the R2 values ranging from 0.94 to 0.99.Conclusions Our result showed that the artificially cultivated moss, which was induced by moss spores and biochar, decreased soil evaporation by reducing soil surface cracks, increasing soil moisture and soil surface temperature.Moss colonization and biochar application has the potential to facilitate soil moisture conservation in karst mountain lands.

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