Pressure drop in selected porous materials used for thermal regenerators

In the present study modeling of permeability of open-porosity ceramic materials used in non-polarizing electrodes is addressed. The structure of the material filling the electrode determines the infiltration of the ceramic structure by electrolyte, which influences the efficiency of the electrodes. The composition of electrode material was characterized with Scanning Electron Microscope Hitachi S3500N with EDS detector and the structure was determined with use of XRadia XCT400 tomograph . The complex geometry of porous materials has been designed using procedure based on Laguerre-Voronoi tessellations (LVT). A set of porous structures with different geometrical features has been developed using LVT algorithm. The approach used here allows to investigate the influence of geometrical features such pore size variation on the permeability of studied materials. Pressure drop characteristics of the developed structures has been analyzed using finite volume method (FVM). The results show that permeability of porous materials is strongly related with distribution of pore size. The study exhibits the utility of developed design procedure for optimization of non-polarizing electrodes performance.

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The Effect of the Presence of Very Cohesive Geldart C Ultra-Fine Particles on the Fluidization of Geldart A Fine Particle Beds

Processes ◽

10.3390/pr7010035 ◽

2019 ◽

Vol 7 (1) ◽

pp. 35 ◽

Cited By ~ 2

Author(s):

Abbas Kamranian Marnani ◽

Andreas Bück ◽

Sergiy Antonyuk ◽

Berend van Wachem ◽

Dominique Thévenin ◽

...

Keyword(s):

Pressure Drop ◽

Fine Particles ◽

Mean Values ◽

Fine Powders ◽

Group A ◽

Total Mixture ◽

The Subject ◽

Materials Used ◽

Ultra Fine Particles ◽

Particle Beds

The effect of the presence of ultra-fines (d < 10 μm) on the fluidization of a bed containing fine particles (d < 100 μm), is the subject of this paper. Practically, it can happen due to breakage or surface abrasion of the fine particles in some processes which totally changes the size distribution and also fluidization behaviour. The materials used in this study are both ground calcium carbonate (GCC); fine is CALCIT MVT 100 (Geldart’s group A) and ultra-fine is CALCIT MX 10 (group C). The experimental results for different binary mixtures of these materials (ultra-fines have 30%, 50%, or 68% of the total mixture weight) show that the physical properties of the mixtures are close to those of pure ultra-fine powders. Using mean values of the bed pressure drop calculated from several independent repetitions, the fluidization behaviour of different mixtures are compared and discussed. The fluidization behaviour of the mixtures is non-reproducible and includes cracking, channelling and agglomeration (like for pure ultra-fine powders). Increasing the portion of ultra-fine materials in the mixture causes a delay in starting partial fluidization, an increase in the bed pressure drop as well as a delay in reaching the peak point.

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Application of Porous Materials to Annular Plain Seals: Part 1—Static Characteristics

Journal of Tribology ◽

10.1115/1.3261991 ◽

1989 ◽

Vol 111 (4) ◽

pp. 655-660 ◽

Cited By ~ 3

Author(s):

S. Kaneko

Keyword(s):

Pressure Drop ◽

Laminar Flow ◽

Porous Materials ◽

Continuity Equation ◽

Reynolds Equation ◽

Porous Matrix ◽

Fluid Film ◽

Force Component ◽

Static Characteristics ◽

Axial Acceleration

Porous materials are applied to the annular plain seals employed in pumps by insertion into the inlet part of the seal. The static characteristics of the seals with the porous materials are studied in the laminar-flow regime. The Reynolds equation for the fluid film in the seal clearance is modified to include a so-called filter term, and the pressure equation for the porous matrix is obtained from Darcy’s law and the continuity equation. These equations are applied to the system and are numerically solved with the pressure drop mainly due to the axial acceleration of liquid at the inlet end of the seal being taken into account. Results show that the annular plain seals with the porous materials have larger fluid film force component along the line of centers and smaller one perpendicular to the former than the ordinary solid seals.

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Pressure Drop Measurement of Porous Materials: Flashback Arrestors for a N2O/C2H4 Premixed Green Propellant

52nd AIAA/SAE/ASEE Joint Propulsion Conference ◽

10.2514/6.2016-5094 ◽

2016 ◽

Cited By ~ 2

Author(s):

Lukas K. Werling ◽

Steffen Müller ◽

Andreas Hauk ◽

Helmut K. Ciezki ◽

Stefan Schlechtriem

Keyword(s):

Pressure Drop ◽

Porous Materials ◽

Green Propellant

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Analysis of Transport Processes for Layered Porous Materials Used in Industrial Applications

Mathematics — Key Technology for the Future ◽

10.1007/978-3-642-55753-8_20 ◽

2003 ◽

pp. 243-251 ◽

Cited By ~ 1

Author(s):

H. Neunzert ◽

A. Zemitis ◽

K. Velten ◽

O. Iliev

Keyword(s):

Porous Materials ◽

Industrial Applications ◽

Transport Processes ◽

Materials Used

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Similarity rule between heat transfer and pressure drop of porous materials

AIChE Journal ◽

10.1002/aic.690381115 ◽

1992 ◽

Vol 38 (11) ◽

pp. 1840-1842 ◽

Cited By ~ 11

Author(s):

Kenji Fukuda ◽

Tetsuya Kondoh ◽

Shu Hasegawa

Keyword(s):

Heat Transfer ◽

Pressure Drop ◽

Porous Materials ◽

Similarity Rule

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Acoustic performance of countersunk micro-perforated panel in multilayer porous material

Building Acoustics ◽

10.1177/1351010x19886588 ◽

2019 ◽

Vol 27 (1) ◽

pp. 3-20 ◽

Cited By ~ 1

Author(s):

L Yuvaraj ◽

S Jeyanthi

Keyword(s):

Additive Manufacturing ◽

Porous Material ◽

Porous Materials ◽

Transfer Matrix Method ◽

Sound Absorption ◽

Integration Method ◽

Absorption Bandwidth ◽

Acoustic Performance ◽

Hole Profile ◽

Materials Used

This study investigates the acoustic performance of a countersunk micro-perforated panel, along with two distinct porous materials used in a multilayer porous absorber configuration. Additive manufacturing is applied to create sub-millimeter perforation with different hole spacings on polymer micro-perforated panels. Experiments are conducted in an impedance tube, in which the effects of the perforation ratio, air gap, and varying porous layer configurations on the sound absorption capabilities are investigated. For validation, considering the converging hole profile in the micro-perforated panel, an integration method with end correction is used to calculate the tapered section impedance, and the traditional Maa theory is used for the uniform hole. The theoretical impedance of the multilayer absorber is calculated using the transfer matrix method and subsequently compared to the experimental results. The results demonstrate that the countersunk hole micro-perforated panel exhibits a significant improvement in sound absorption, and the introduction of porous materials extends the sound absorption bandwidth. Furthermore, the results indicate that the sound absorption capability depends on the porous material placement in the multilayer absorber configuration.

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