CFD Simulations Devoted to the Study of Fitting Effects on the Phase Distribution in Parallel Vertical Channels
-
F. Devia
,
M. Fossa
Abstract
Uneven distribution of phases in plate heat exchangers is a cause of reduction in both thermal and fluid-dynamic performances. With respect to two-phase flows, phase separation in manifolds with several outlets is a complex phenomenon and no general rules are available for predicting the phase distribution at header–channel junctions. The design of compact heat exchangers and their distributors is still based on empirical approaches and both experimentation and numerical analyses are needed for defining the best geometries able to reduce the mass flow rate non-uniformities in parallel channels. In this paper, a series of CFD simulations are carried out to infer the effects of a protrusion fitting (inside the header) on the single-phase distribution in parallel upward vertical channels fed by a common horizontal distributor. The numerical results are compared with both experimental single-phase and two-phase (liquid/gas) experimental data. The effects of the operating conditions are investigated and general conclusions on the differences and analogies between single-phase and two-phase flows in the present problem are discussed.
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©2015 by De Gruyter
Articles in the same Issue
- 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
Articles in the same Issue
- 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
