scholarly journals Mathematical model of multicomponent mixture flow of gases with regard to the possibility of the liquid phase

2018 ◽  
pp. 1-36
Author(s):  
Victor Timofeevich Zhukov ◽  
Yuri Germanovich Rykov ◽  
Olga Borisovna Feodoritova
Keyword(s):  
Mathematical Model ◽  
Liquid Phase ◽  
Multicomponent Mixture ◽  
Mixture Flow

Modeling of aerated upflow fixed bed reactors for nitrification

1999 ◽  
Vol 39 (4) ◽  
pp. 85-92 ◽  
Author(s):  
J. Behrendt
Keyword(s):  
Mathematical Model ◽  
Mass Transfer ◽  
Liquid Phase ◽  
Gas Phase ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Bulk Liquid ◽  
Initial Value ◽  
Fixed Bed Reactors ◽  
Number Of Cells

A mathematical model for nitrification in an aerated fixed bed reactor has been developed. This model is based on material balances in the bulk liquid, gas phase and in the biofilm area. The fixed bed is divided into a number of cells according to the reduced remixing behaviour. A fixed bed cell consists of 4 compartments: the support, the gas phase, the bulk liquid phase and the stagnant volume containing the biofilm. In the stagnant volume the biological transmutation of the ammonia is located. The transport phenomena are modelled with mass transfer formulations so that the balances could be formulated as an initial value problem. The results of the simulation and experiments are compared.

Application of a Bubble-Induced Turbulence Model to Subcooled Boiling in a Vertical Pipe

1999 ◽  
Author(s):  
Mahmut D. Mat ◽  
Yüksel Kaplan ◽  
Olusegun J. Ilegbusi
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Liquid Phase ◽  
Turbulence Model ◽  
Transport Equations ◽  
Subcooled Boiling ◽  
Vertical Pipe ◽  
Void Fractions ◽  
Turbulence Production ◽  
The Mathematical Model

Abstract Subcooled boiling of water in a vertical pipe is numerically investigated. The mathematical model involves solution of transport equations for vapor and liquid phase separately. Turbulence model considers the turbulence production and dissipation by the motion of the bubbles. The radial and axial void fractions, temperature and velocity profiles in the pipe are calculated. The estimated results are compared to experimental data available in the literature. It is found that while present study satisfactorily agrees with experimental data in the literature, it improves the prediction at lower void fractions.

scholarly journals Mathematical model study on the damage of the liquid phase to productivity in the gas reservoir with a bottom water zone

Petroleum ◽  
2018 ◽  
Vol 4 (2) ◽  
pp. 209-214 ◽  
Author(s):  
Xiaoliang Huang ◽  
Xiao Guo ◽  
Xinqian Lu ◽  
Xiang Zhou ◽  
Zhilin Qi ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Liquid Phase ◽  
Bottom Water ◽  
Gas Reservoir ◽  
Water Zone ◽  
Model Study

scholarly journals DETERMINATION OF CHARACTERISTICS AND SMOKE EXHAUSTERS PARAMETERS IN CONDITIONS OF INDEPENDED AND JOINT WORK WITH OTHER DEVICES BASED ON MATHEMATICAL MODEL

2018 ◽  
Vol 1 (2) ◽  
pp. 10-17
Author(s):  
A Kodryk ◽  
O Titenko ◽  
V Prysiazhniuk ◽  
S Semychaievskyi
Keyword(s):  
Mathematical Model ◽  
Aerodynamic Resistance ◽  
Exhaust System ◽  
Axially Symmetric ◽  
Axial Fan ◽  
Joint Work ◽  
Mixture Flow ◽  
Operating Modes ◽  
Table Data ◽  
Independent Work

The principle of construction and examples of implementation of the developed mathematical model of the smoke exhaust system designed for operational use in case of fire for the elimination of gas pollution and lowering the temperature in the premises. Estimated target features of the installation are based on existing experience, namely: expected aerodynamic airway resistance: 80 Pa and volumetric air mixture flow rate of 3.3 m3/s. The specified characteristics and parameters necessary for the design, or modernization of existing axial fans, and their choice for three operating modes: independent work, joint work with the supply of finely divided water, joint work with the foam generating plant. Simplifications were used in the development of a mathematical model: scheme of the design of the axial fan, which does not involve the presence of a guiding apparatus; it is assumed that the flow in the operating cavity of the pump is axially symmetric; it is assumed that the thermodynamic process taking place in the pump cavity is isothermal; simplified formula of the lifting factor and drag coefficient of the grid is used on the basis of known table data. The mathematical model takes into account: the dimensions of the smoke exhaust system, the number and size of the blades, the angle of attack of the blade, the frequency of rotation, the amount of aerodynamic resistance of the airway, the density and the amount of supply of finely divided water or foam. The examples of the implementation of the developed mathematical model of the smoke exhaust system are illustrated in the form of diagrams of the location of the working points (volume flow of air mixture, m3/s, pressure, Pa; power of the engine of the smoke exhaust system, W) at operation of a smoke exhaust system in the conditions of the average airway for the three above-mentioned operating modes.

Solving Practical Industrial Problems in Two-Phase Multicomponent Mixture Flow - Critical Velocity

2001 ◽  
Vol 22 (1) ◽  
pp. 32-40 ◽  
Author(s):  
J. Kohoutek ◽  
J. Zachoval ◽  
M. Odstrcil ◽  
P. Stehlik
Keyword(s):  
Critical Velocity ◽  
Multicomponent Mixture ◽  
Two Phase ◽  
Mixture Flow

The Temperature Dependence of Band Maxima Molar Absorptivities of the Carbon-Halogen Stretching Mode in Tertiary Butyl Chloride, Bromide, and Iodide in the Liquid Phase

1987 ◽  
Vol 41 (3) ◽  
pp. 468-471 ◽  
Author(s):  
J. E. Katon ◽  
Stanislaus R. Lobo ◽  
J. C. Simpson
Keyword(s):  
Mathematical Model ◽  
Liquid Phase ◽  
Temperature Dependence ◽  
Linear Relationship ◽  
Molar Absorptivity ◽  
Absolute Temperature ◽  
Significant Error ◽  
Butyl Chloride ◽  
Tertiary Butyl ◽  
Relationship Of

The absorbances at the peak maxima of the carbon-halogen stretching mode of t-butyl chloride, bromide, and iodide have been measured as a function of temperature. With the use of corrected concentration and pathlengths, these data have been converted into molar absorptivities at the respective peak maxima. The data have then been analyzed statistically for the purpose of developing a mathematical model for the dependency of molar absorptivity, at these peak maxima, on the absolute temperature. In all three cases, a linear relationship of the form e = XT + Y was found to satisfactorily fit the data. The molar absorptivity of all three band maxima decreases approximately 1% per Kelvin. This result indicates that attempts to apply Beer's law at temperatures other than that used to derive the constants will lead to significant error if the temperatures differ by more than a few degrees.

Dissolved Oxygen Convection and Diffusion Numerical Simulation of Water and Air Mixture Flow in Circular Pipe

2011 ◽  
Vol 383-390 ◽  
pp. 6651-6656
Author(s):  
Ze Gao Yin ◽  
Xian Wei Cao ◽  
Dong Sheng Cheng ◽  
Le Wang
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Dissolved Oxygen ◽  
Oxygen Concentration ◽  
Pipe Flow ◽  
Concentration Distribution ◽  
Dissolved Oxygen Concentration ◽  
Mixture Flow ◽  
Velocity Pressure ◽  
And Diffusion

In Fluent, the 3-D RNG k–ε mathematical model is employed to compute water and air mixture pipe flow. The dissolved oxygen convectionaεnd diffusion model is established to simulate the concentration distribution of dissolved oxygen with user defined scalar method. Velocity, pressure and dissolved oxygen concentration are computed. Then, dissolved oxygen concentration and pressure are compared with the data of physical model, and they agree with each other approximately, showing it is valid and reliable to compute the mixture pipe flow and dissolved oxygen concentration with the model .Furthermore, under a specific condition, velocity, pressure and dissolved oxygen concentration of water and air mixture pipe flow are computed and their characteristics are analyzed.

The Temperature Dependence of Band Maxima Molar Absorptivities of the Carbon-Bromine Stretching Modes in n-Butyl Bromide in the Liquid Phase

1987 ◽  
Vol 41 (5) ◽  
pp. 807-809 ◽  
Author(s):  
J. E. Katon ◽  
Stanislaus R. Lobo ◽  
J. C. Simpson
Keyword(s):  
Mathematical Model ◽  
Infrared Spectroscopy ◽  
Liquid Phase ◽  
Temperature Dependence ◽  
Energy Difference ◽  
Temperature Dependent ◽  
Butyl Bromide ◽  
Absorption Bands ◽  
A Value

In the determination of energy differences of conformers in the fluid states by infrared spectroscopy it is nearly always assumed that the ratio of the molar absorptivities at the band maxima of two separate absorption bands is independent of temperature. This assumption has been tested by fitting the data obtained from n-butyl bromide to a mathematical model which can be iterated to convergence on a value of the energy difference between the trans and gauche isomers. The data utilized are the C-Br stretching modes of the two conformers at about 655 and 567 cm−1, respectively. It is shown that the assumption of temperature independence of the ratios of the molar absorptivities at the peak maxima is a good one, although both values are individually temperature dependent.

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