A CFD Study on Two-Phase Frozen Flow of Air/Water Through a Safety Relief Valve
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Moftah Alshaikh
Abstract
The air-water two phase critical flows through a safety relief valve commonly used in the refrigeration industry is examined with particular emphasis on the prediction of the critical mass flowrates using CFD based approaches. The expansion of the gas through the valve and the associated acceleration is coupled to the liquid phase and results in changes to the velocity slip with the possibility of influencing the choking conditions and the magnitude of the critical mass flows. These conditions are poorly reported in the literature for safety valves. This paper presents a study where the ability of established two phase multi-dimensional modelling approaches to predict such conditions are investigated. Comparison with the simplified mixture model will show that this model tends to underestimate mass flowrates for medium to high liquid mass fraction. However, the two fluid model can adequately account for the thermal and mechanical non equilibrium for these complex flow conditions with the use of simplified droplet sizing rules.
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©2015 by De Gruyter
Artikel in diesem Heft
- Frontmatter
- Editorial
- Special Issue Published in the Occasion of the 13th International Conference on Multiphase Flows in Industrial Plants (13th MFIP) held in Sestri Levente (Italy) from the 17th to the 19th of September 2014
- Special Issue Articles
- Behaviour and Stability of the Two-Fluid Model for Fine-Scale Simulations of Bubbly Flow in Nuclear Reactors
- A Model on the Stability of a Pipe in an Aerated Silo
- Enhancement of MSF Using Microbubbles
- Single Air Bubble Breakup Experiments in Stirred Water Tank
- Frictional Pressure Drop during Two-Phase Flow of Pure Fluids and Mixtures in Small Diameter Channels
- A Practical Approach to Operational Hydrodynamic Slug Analysis in Pipelines
- The Thermosiphon Cooling System of the ATLAS Experiment at the CERN Large Hadron Collider
- Energy Intensity Reduction of Ca-Looping CO2 Capture by Applying Mixing Loop Seals and Cyclonic Systems
- A CFD Study on Two-Phase Frozen Flow of Air/Water Through a Safety Relief Valve
- CFD Study of the Hydrodynamics of Slug Flow Systems: Interaction between Consecutive Taylor Bubbles
- CFD Simulations Devoted to the Study of Fitting Effects on the Phase Distribution in Parallel Vertical Channels
Artikel in diesem Heft
- Frontmatter
- Editorial
- Special Issue Published in the Occasion of the 13th International Conference on Multiphase Flows in Industrial Plants (13th MFIP) held in Sestri Levente (Italy) from the 17th to the 19th of September 2014
- Special Issue Articles
- Behaviour and Stability of the Two-Fluid Model for Fine-Scale Simulations of Bubbly Flow in Nuclear Reactors
- A Model on the Stability of a Pipe in an Aerated Silo
- Enhancement of MSF Using Microbubbles
- Single Air Bubble Breakup Experiments in Stirred Water Tank
- Frictional Pressure Drop during Two-Phase Flow of Pure Fluids and Mixtures in Small Diameter Channels
- A Practical Approach to Operational Hydrodynamic Slug Analysis in Pipelines
- The Thermosiphon Cooling System of the ATLAS Experiment at the CERN Large Hadron Collider
- Energy Intensity Reduction of Ca-Looping CO2 Capture by Applying Mixing Loop Seals and Cyclonic Systems
- A CFD Study on Two-Phase Frozen Flow of Air/Water Through a Safety Relief Valve
- CFD Study of the Hydrodynamics of Slug Flow Systems: Interaction between Consecutive Taylor Bubbles
- CFD Simulations Devoted to the Study of Fitting Effects on the Phase Distribution in Parallel Vertical Channels
