scholarly journals Modelling Macrophage Infiltration into Avascular Tumours

2002 ◽  
Vol 4 (1) ◽  
pp. 21-38 ◽  
Author(s):  
C. E. Kelly ◽  
R. D. Leek ◽  
H. M. Byrne ◽  
S. M. Cox ◽  
A. L. Harris ◽  
...  
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Spatial Structure ◽  
Random Motion ◽  
Numerical Results ◽  
Macrophage Infiltration ◽  
Numerical Techniques ◽  
Model Predictions ◽  
Independent Experimental Data

In this paper a mathematical model that describes macrophage infiltration into avascular tumours is presented. The qualitative accuracy of the model is assessed by comparing numerical results with independent experimental data that describe the infiltration of macrophages into two types of spheroids: chemoattractant-producing (hepa-1) and chemoattractant-deficient (or C4) spheroids. A combination of analytical and numerical techniques are used to show how the infiltration pattern depends on the motility mechanisms involved (i.e. random motion and chemotaxis) and to explain the observed differences in macrophage infiltration into the hepa-1 and C4 spheroids. Model predictions are generated to show how the spheroid's size and spatial structure and the ability of its constituent cells influence macrophage infiltration. For example, chemoattractant-producing spheroids are shown to recruit larger numbers of macrophages than chemoattractant-deficient spheroids of the same size and spatial structure. The biological implications of these results are also discussed briefly.

CH4 Direct Reduction of In-Flight Fe3O4 Concentrate Particles

2018 ◽  
Vol 14 (1) ◽  
Author(s):  
Bahador Abolpour ◽  
M. Mehdi Afsahi ◽  
Ataallah Soltani Goharrizi
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Fine Particles ◽  
Direct Reduction ◽  
Constant Heat Flux ◽  
Constant Heat ◽  
Dynamic Motion ◽  
Magnetite Ore ◽  
Model Predictions ◽  
Kinetics Of

Abstract In this study, reduction of in-flight fine particles of magnetite ore concentrate by methane at a constant heat flux has been investigated both experimentally and numerically. A 3D turbulent mathematical model was developed to simulate the dynamic motion of these particles in a methane content reactor and experiments were conducted to evaluate the model. The kinetics of the reaction were obtained using an optimizing method as: [-Ln(1-X)]1/2.91 = 1.02 × 10−2dP−2.07CCH40.16exp(−1.78 × 105/RT)t. The model predictions were compared with the experimental data and the data had an excellent agreement.

Pretreatment of Textile Industry Wastewaters with Ozone

1994 ◽  
Vol 29 (9) ◽  
pp. 151-160 ◽  
Author(s):  
M. Tzitzi ◽  
D. V. Vayenas ◽  
G. Lyberatos
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Textile Industry ◽  
Batch Studies ◽  
Cod Reduction ◽  
Industrial Wastewaters ◽  
Model Predictions ◽  
Textile Wastewaters

Ozonation of textile industrial wastewaters was examined in CSTR and batch studies. Experiments were done for various types of textile wastewaters and for different reaction and retention times. Much better results were obtained using ozonation after the coagulation-precipitation stage. Also a mathematical model was developed, able to describe wastewater decolonization and COD reduction. In all cases the comparison between the model predictions and the experimental data was satisfactory.

Mathematical Modeling of Capillary Pumping Within Micron Sized Channels

2013 ◽  
Author(s):  
Yuelei Yang ◽  
Dan Zhang
Keyword(s):  
Mathematical Modeling ◽  
Experimental Data ◽  
Mathematical Model ◽  
Capillary Pressure ◽  
Heat Engine ◽  
Velocity Profiles ◽  
Vof Method ◽  
Numerical Results ◽  
Micro Heat Engine ◽  
Volume Of Fluids

This paper introduces a mathematical model which can be used to simulate the capillary pumping process of a micro heat engine. The micro heat engine has micron sized channels where the capillary pumping occurs. The classic Volume of Fluids (VOF) method is applied to obtain the velocity profiles of the fluids and to track the motions of the liquid-gas interfaces. The numerical results based this model have been compared with the experimental data and the initial retard of the pumping has been found and this phenomenon can be explained by the initial capillary pressure build-ups across the liquid-gas interfaces.

The Dynamics of Liquid Cooling in Half-Coil Jackets

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Jayakumar Natesan Subramanian ◽  
Farouq S. Mjalli
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Mathematical Model ◽  
Liquid Temperature ◽  
Liquid Cooling ◽  
Shell Side ◽  
Stirred Vessel ◽  
Model Predictions ◽  
Temperature Dynamics ◽  
The Heat Transfer Coefficient

The heat transfer cooling of a hot liquid in a stirred vessel has been studied experimentally with coolant flowing through a half-coil around the vessel. Correlations have been developed for the heat transfer coefficient of the half coil jacket. A mathematical model for the half coil jacket liquid temperature dynamics and its analytical solution is used to find the shell side temperature profile as a function of time. It is found that the model predictions are in satisfactory agreement with the experimental data and that the developed correlation is superior to previously published correlations for similar systems.

scholarly journals Mathematical Model of VOCs Emission in Three-layer Building Materials

2021 ◽  
Vol 257 ◽  
pp. 03047
Author(s):  
Zhehua Du ◽  
Xin Lin
Keyword(s):  
Experimental Data ◽  
Boundary Layer ◽  
Mathematical Model ◽  
Building Materials ◽  
Present Model ◽  
Transfer Resistance ◽  
Model Predictions ◽  
Layer Resistance ◽  
Boundary Layer Resistance ◽  
Good Agreement

A simple mathematical model is proposed to account for emissions of Volatile Organic Compounds (VOCs) from three-layer building materials. The model considers both the diffusion within three layer building materials and the mass transfer resistance through the air boundary layer. A general solution method based on Laplace transform is presented. Compared to other models capable of accounting for emissions of VOCs from multi layer building materials, the present model is fully analytical instead of being numerical. The present model was validated by the experimental data from the specially designed test. The results indicated that there was a good agreement between the model predictions and the experimental data. It can also be seen from calculation that model ignoring the boundary layer resistance cannot fully reflect the real situation.

Numerical Study of the Dynamics of Particles Motion with Different Sizes from Coal-Based Thermal Power Plant

2019 ◽  
Vol 20 (2) ◽  
pp. 223-241 ◽  
Author(s):  
Alibek Issakhov ◽  
Ruslan Bulgakov ◽  
Yeldos Zhandaulet
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Mathematical Model ◽  
Power Plant ◽  
Thermal Power Plant ◽  
Thermal Power ◽  
Numerical Results ◽  
Simulation Results ◽  
Turbulent Models ◽  
The Mathematical Model

AbstractIn this paper, the propagation of particles with different sizes from a coal-based thermal power plant was investigated. It was found that the deterioration of the environment is due to the release of a large amount of SOx, NOx and the volatile particles of Suspended Particulate Matter and Respirable Suspended Particles matter, which cause human and animal diseases. This paper presents the numerical simulation results of air pollution by particles which having different sizes from thermal power plants in real sizes using a 3D model. For the adequacy of the mathematical model, a test problem was solved using different turbulent models. To assess the applicability of the mathematical model, the numerical algorithm and the choice of the optimal turbulent model, experimental data and numerical results of other authors were used. The obtained numerical simulation results are in good agreement with the experimental results and the numerical results of other authors. And to obtain more accurate numerical results for the experimental data for turbulent models ($k - \varepsilon $,$k - \omega $), there were certain corresponding boundary conditions for kinetic energy. Also, profiles of all flow characteristics were compared with and without particles and some effects of the particle on the flow were identified.

MATHEMATICAL MODEL FOR HEAT DEPOSITION IN TISSUE DURING PHOTODYNAMICAL THERAPY

1996 ◽  
Vol 04 (02) ◽  
pp. 261-276
Author(s):  
ALFRED ŠVARC ◽  
MISLAV JURIN ◽  
SUZANA BOROVIĆ ◽  
HRVOJE ZORC ◽  
MARKO DOKO
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Theoretical Model ◽  
Light Source ◽  
Normal Tissue ◽  
Treatment Time ◽  
Red Light ◽  
Heat Deposition ◽  
Model Predictions

A mathematical model for the heat deposition in tissue during the exposition to the red light, essential for the phototherapy, is presented. The comparison of model predictions with in vivo experimental data for the normal CBA/HZgr mice hind leg tissue is done in order to illustrate the domain of confidence of the theoretical model. The highest usable power of the light source, and consequently the lowest phototherapy treatment time with no influence upon normal tissue is determined.

Predictions of the Structure of Turbulent, Moderately Underexpanded Jets

1994 ◽  
Vol 116 (4) ◽  
pp. 707-713 ◽  
Author(s):  
P. S. Cumber ◽  
M. Fairweather ◽  
S. A. E. G. Falle ◽  
J. R. Giddings
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Dissipation Rate ◽  
Integration Scheme ◽  
Rate Model ◽  
Flow Equations ◽  
Underexpanded Jets ◽  
Model Predictions ◽  
Volume Integration ◽  
Grid Algorithm

A mathematical model capable of predicting the structure of turbulent, underexpanded jets is described. The model is based on solutions of the fluid flow equations obtained using a second-order accurate, finite-volume integration scheme coupled to an adaptive grid algorithm. Turbulence within these jets is modelled using a k-ε approach coupled to the compressible dissipation rate model of Sarkar et al. (1991a). Comparison of model predictions and experimental data, reported in the literature, on a number of moderately underexpanded jets demonstrate significant improvements over results derived using the standard k-ε approach, and the adequacy of the compressibility corrected turbulence model for predicting such jets.

A STATISTICAL ANALYSIS OF GRAIN COUNTING IN PHOTOGRAPHIC EMULSIONS

1952 ◽  
Vol 30 (6) ◽  
pp. 699-714 ◽  
Author(s):  
W. W. Happ ◽  
T. E. Hull ◽  
A. H. Morrish
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Statistical Analysis ◽  
Physical Properties ◽  
Frequency Distribution ◽  
Charged Particles ◽  
Numerical Results ◽  
Statistical Problems ◽  
Photographic Emulsions ◽  
Good Agreement

Fluctuations in the grain density of tracks of charged particles passing through photographic emulsions are examined in terms of the physical properties of grains and the type of counting convention used. A mathematical model, for one counting convention which takes into account both the frequency distribution of the grains and the frequency distribution of their lengths, yields numerical results in good agreement with experimental data. Other statistical problems of interest in grain counting are discussed.

Sign in / Sign up

Export Citation Format

Share Document