Diffusion form of the transport equation and the method of kinetic diffusion (application to one-dimensional planar geometry)

Atomic Energy ◽  
1999 ◽  
Vol 86 (1) ◽  
pp. 13-25 ◽  
Author(s):  
V. V. Seliverstov
Keyword(s):  
Transport Equation ◽  
Planar Geometry ◽  
One Dimensional ◽  
Kinetic Diffusion ◽  
Diffusion Form

Two-Fluid CFD Model of Adiabatic Air-Water Upward Bubbly Flow Through a Vertical Pipe With a One-Group Interfacial Area Transport Equation

2009 ◽  
Author(s):  
Deoras Prabhudharwadkar ◽  
Chris Bailey ◽  
Martin Lopez de Bertodano ◽  
John R. Buchanan
Keyword(s):  
Experimental Data ◽  
Transport Equation ◽  
Bubbly Flow ◽  
Interfacial Area ◽  
Correct Prediction ◽  
Interfacial Area Transport ◽  
One Dimensional ◽  
Interfacial Area Transport Equation ◽  
The One ◽  
Two Fluid

This paper describes in detail the assessment of the CFD code CFX to predict adiabatic liquid-gas two-phase bubbly flow. This study has been divided into two parts. In the first exercise, the effect of Lift Force, Wall Force and the Turbulent Diffusion Force have been assessed using experimental data from the literature for air-water upward bubbly flows through a pipe. The data used here had a characteristic near wall void peaking which was largely influenced by the joint action of the three forces mentioned above. The simulations were performed with constant bubble diameter assuming no bubble interactions. This exercise resulted in selection of the most appropriate closure form and closure coefficients for the above mentioned forces for the range of flow conditions chosen. In the second exercise, the One-Group Interfacial Area Transport equation was introduced in the two-fluid model of CFX. The interfacial area density plays important role in the correct prediction of interfacial mass, momentum and energy transfer and is affected by bubble breakup and coalescence processes in adiabatic flows. The One-Group Interfacial Area Transport Equation (IATE) has been developed and implemented for one-dimensional models and validated using cross-sectional area averaged experimental data over the last decade by various researchers. The original one-dimensional model has been extended to multidimensional flow predictions in this study and the results are presented in this paper. The paper also discusses constraints posed by the commercial CFD code CFX and the solutions worked out to obtain the most accurate implementation of the model.

L[sup 1]-Uniqueness of Weak Solution for One-Dimensional mass Transport Equation

2009 ◽  
Author(s):  
Ludovic Dan Lemle ◽  
Tudor Bi^nzar ◽  
Flavius Pater ◽  
Theodore E. Simos ◽  
George Psihoyios ◽  
...  
Keyword(s):  
Weak Solution ◽  
Mass Transport ◽  
Transport Equation ◽  
One Dimensional ◽  
Mass Transport Equation

The LTSNsolution of the transport equation for one-dimensional cartesian geometry withc= 1

Kerntechnik ◽  
2008 ◽  
Vol 73 (1-2) ◽  
pp. 57-60 ◽  
Author(s):  
C. F. Segatto ◽  
M. T. Vilhena ◽  
D. V. Marona
Keyword(s):  
Transport Equation ◽  
One Dimensional ◽  
Cartesian Geometry

First bent form for the hydroxo-bridged cis-diammineplatinum(II) dimer [Pt2(NH3)4(μ-OH)2](ClO4)2

2004 ◽  
Vol 60 (3) ◽  
pp. 255-262 ◽  
Author(s):  
Ken Sakai ◽  
Yosuke Konno ◽  
Noboru Takayama ◽  
Satoru Takahashi
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Planar Geometry ◽  
One Dimensional ◽  
The Third ◽  
Geometrical Features ◽  
Hydrogen Bonding Network ◽  
The One ◽  
Carbonate Salts ◽  
Perchlorate Salt

The third crystal structure containing the hydroxo-bridged cis-diammineplatinum(II) dimer has been determined for a perchlorate salt of the complex, [Pt2(NH3)4(μ-OH)2](ClO4)2. However, the dinuclear cations in the nitrate and the carbonate salts, [Pt2(NH3)4(μ-OH)2](NO3)2 [Faggiani, Lippert, Lock & Rosenberg (1977). J. Am. Chem. Soc. 99, 777–781] and [Pt2(NH3)4(μ-OH)2](CO3)·H2O [Lippert, Lock, Rosenberg & Zvagulis (1978). Inorg. Chem. 17, 2971−2975], were reported to possess a nearly planar geometry. The cation in the title perchlorate salt has been found to possess an exceptional bent form in which two Pt coordination planes within the dimer are tilted at an angle of 151.7 (1)° to one another. The diplatinum entity has a syn orientation with regard to the conformation of two hydroxo bridges, in part due to the one-dimensional hydrogen-bonding network achieved in the crystal structure. DFT MO investigations have also been carried out to reveal that the planar-bent selection could be induced by the anti–syn selection at the H(hydroxo) atoms. Comparison has also been made between the geometrical features of the three salts from the viewpoint of the orientation of H(hydroxo) atoms.

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