An Analytical Examination of the Behavior of Oil Sand Fragments in Heated Streams

1982 ◽  
Vol 104 (2) ◽  
pp. 121-129
Author(s):  
A. Hanafi ◽  
G. A. Karim
Keyword(s):  
Analytical Study ◽  
Chemical Processes ◽  
Operating Conditions ◽  
Transient Effects ◽  
Oil Sand ◽  
Wide Range ◽  
Experimental Values ◽  
Physical And Chemical ◽  
Simultaneous Heat ◽  
Good Agreement

The physical and chemical processes that occur typically within and around an oil sand fragment are considered when the fragment is suddenly introduced into a hot, low-uniform velocity, gaseous oxidizing stream. In this analytical study, the extent of bitumen volatilization was obtained from a consideration of the simultaneous heat and mass transfer within spherical oil sand fragments combined with a simplified cracking scheme of the heavy oil and asphaltene into coke and distillate. The resulting system of equations together with the boundary conditions arising from subjecting the fragments to hot convective streams were solved using Laplace transformation. The transient concentrations of bitumen and temperature within the fragments were then obtained under a wide range of operating conditions. The similarity of the expression obtained for the extent of bitumen volatilization to the expression derived from simplified analysis, based on a dropletlike model, was demonstrated for cases where the transient effects within the fragments were considered to be negligible. The results of the theoretical analysis show relatively good agreement with their corresponding experimental values at high stream temperatures, while they showed relatively inferior agreement at low temperatures.

An Analytical Study of Heat and Mass Transfer Within an Oil Sand Bed

1987 ◽  
Vol 109 (2) ◽  
pp. 66-70
Author(s):  
M. A. Abdrabboh ◽  
G. A. Karim
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Oil Sands ◽  
Operating Conditions ◽  
Oil Sand ◽  
Mass Transfer Processes ◽  
Wide Range ◽  
Gaseous Stream ◽  
Fluid Concentration ◽  
Experimental Values

The physical processes that occur typically within an oil sand bed are considered when the bed is subjected to a hot gaseous stream. In this study, the extent of fluid volatilization was obtained from a consideration of the simultaneous heat and mass transfer processes within the oil sands. The resulting system of equations together with the boundary conditions were solved numerically using an implicit finite difference method. The transient fluid concentration and temperature distributions within the oil sand bed were then obtained under a wide range of operating conditions. The resulting theoretical rates of volatilization and temperatures show generally good agreement with corresponding experimental values that were obtained for the purpose.

scholarly journals DFT calculation and assignment of vibrational spectra of aryl and alkyl chlorophosphates

2014 ◽  
Vol 12 (2) ◽  
pp. 153-163
Author(s):  
Viktor Anishchenko ◽  
Vladimir Rybachenko ◽  
Konstantin Chotiy ◽  
Andrey Redko
Keyword(s):  
Vibrational Spectra ◽  
Basis Sets ◽  
Heavy Atoms ◽  
Wide Range ◽  
Complete Assignment ◽  
Key Factor ◽  
Polarization Functions ◽  
Experimental Values ◽  
Semi Empirical ◽  
Good Agreement

AbstractDFT calculations of vibrational spectra of chlorophosphates using wide range of basis sets and hybrid functionals were performed. Good agreement between calculated and experimental vibrational spectra was reached by the combination of non-empirical functional PBE0 with both middle and large basis sets. The frequencies of the stretching vibrations of the phosphate group calculated using semi-empirical functional B3LYP for all basis sets deviate significantly from the experimental values. The number of polarization functions on heavy atoms was shown to be a key factor for the calculation of vibrational frequencies of organophosphates. The importance of consideration of all the stable rotamers for a complete assignment of fundamental modes was shown.

Transition from dripping to jetting

1999 ◽  
Vol 383 ◽  
pp. 307-326 ◽  
Author(s):  
CHRISTOPHE CLANET ◽  
JUAN C. LASHERAS
Keyword(s):  
Weber Number ◽  
Free Edge ◽  
Newtonian Liquid ◽  
Inviscid Limit ◽  
Inertia Effects ◽  
Wide Range ◽  
Critical Weber Number ◽  
Experimental Values ◽  
Outside Diameter ◽  
Good Agreement

We consider the critical Weber number (Wec≡ ρV20D/σ) at which the transition from dripping to jetting occurs when a Newtonian liquid of density ρ and surface tension σ is injected with a velocity V0 through a tube of diameter D downward into stagnant air, under gravity g. We extend Taylor's (1959) model for the recession speed of a free edge, and obtain in the inviscid limit an exact solution which includes gravity and inertia effects. This solution provides a criterion for the transition which is shown to occur at a critical Weber numberformula herewhere Bo and Boo are the Bond numbers (Bo≡[ρgD2/(2σ)]1/2), respectively based on the inside and outside diameter of the tube, and K is a constant equal to 0.37 for the case of water injected in air. This critical Weber number is shown to be in good agreement with existing experimental values as well as with new measurements performed over a wide range of Bond numbers.

Frequency Response of an Electro-Hydraulic Vibrator with Inertial Load

1966 ◽  
Vol 8 (1) ◽  
pp. 27-35 ◽  
Author(s):  
C. Ashley ◽  
B. Mills
Keyword(s):  
Hydraulic Cylinder ◽  
Operating Conditions ◽  
Dimensionless Number ◽  
Load Compensation ◽  
Second Stage ◽  
The Past ◽  
Linear Transfer Function ◽  
Wide Range ◽  
Mechanical Devices ◽  
Good Agreement

During the past few years systematic vibration testing has played an increasing part in the evaluation of mechanical devices. The electro-hydraulic vibrator, consisting of a valve-controlled hydraulic cylinder, is capable of high thrusts over a fairly wide range of frequency. This paper examines the theoretical behaviour of such a vibrator which is itself similar to a hydraulic positioning system. The cylinder equations are extended to include end leakages and the servo valve is examined both for transfer characteristics and the interdependence of flow and load. It is shown that the classical square root relationship between pressure drop and flow does not necessarily apply for a two-stage valve with a spring-centred second stage and that a dimensionless number known as the valve load compensation coefficient describes these characteristics. For practical valves it is possible for the flow to be almost independent of the load over a wide range of operating conditions and thus a linear transfer function can be used for the valve-cylinder combination. The experimental work shows good agreement between the theoretical characteristics and those found in practice.

VLE Determination of Carbon Dioxide Loaded Aqueous Alkanolamine Mixtures Using Modified Kent Eisenberg Model

2017 ◽  
Vol 231 (11-12) ◽  
Author(s):  
Humbul Suleman ◽  
Abdulhalim Shah Maulud ◽  
Zakaria Man
Keyword(s):  
Experimental Data ◽  
Carbon Dioxide ◽  
Model Parameters ◽  
Thermodynamic Models ◽  
Carbon Dioxide Absorption ◽  
Proposed Model ◽  
Wide Range ◽  
Experimental Values ◽  
Good Agreement

AbstractA computationally simple thermodynamic framework has been presented to correlate the vapour-liquid equilibria of carbon dioxide absorption in five representative types of alkanolamine mixtures. The proposed model is an extension of modified Kent Eisenberg model for the carbon dioxide loaded aqueous alkanolamine mixtures. The model parameters are regressed on a large experimental data pool of carbon dioxide solubility in aqueous alkanolamine mixtures. The model is applicable to a wide range of temperature (298–393 K), pressure (0.1–6000 kPa) and alkanolamine concentration (0.3–5 M). The correlated results are compared to the experimental values and found to be in good agreement with the average deviations ranging between 6% and 20%. The model results are comparable to other thermodynamic models.

Ball Bearing Response to Cage Unbalance

1986 ◽  
Vol 108 (3) ◽  
pp. 462-466 ◽  
Author(s):  
P. K. Gupta ◽  
J. F. Dill ◽  
J. W. Artuso ◽  
N. H. Forster
Keyword(s):  
Entire Range ◽  
High Speed ◽  
Ball Bearing ◽  
Operating Conditions ◽  
Angular Contact Ball Bearing ◽  
Turbine Engine ◽  
Wide Range ◽  
Inner Race ◽  
Good Agreement ◽  
Engine Bearing

Motion of the cage in a high-speed angular contact ball bearing is experimentally investigated as a function of prescribed unbalance, up to operating speeds corresponding to three million DN. The predictions of cage motion made by the recently developed computer model, ADORE, are validated in the light of the experimental data. It is shown the cage whirl velocity is essentially equal to its angular velocity at all levels of unbalance and over a wide range of operating conditions. For the inner race guided turbine engine bearing, the cage/race interaction takes place directly opposite to the location of the unbalance and the severity of the interaction increases with the level of unbalance and the operating speed. ADORE predictions, over the entire range of unbalance and bearing operating conditions, are in very good agreement with the experimental observations.

Lattice-Dynamical Estimation of Atomic Displacement Parameters in Carbonates: Calcite and Aragonite CaCO3, Dolomite CaMg(CO3)2 and Magnesite MgCO3

1998 ◽  
Vol 54 (5) ◽  
pp. 515-523 ◽  
Author(s):  
T. Pilati ◽  
F. Demartin ◽  
C. M. Gramaccioli
Keyword(s):  
Structure Refinement ◽  
Atomic Displacement ◽  
Empirical Potentials ◽  
Wide Range ◽  
Anisotropic Displacement Parameters ◽  
The Stability ◽  
Experimental Values ◽  
Atomic Displacement Parameters ◽  
Good Agreement ◽  
Raman And Ir Spectra

Using crystallographic information and empirical potentials derived from fitting the vibrational frequencies of all the substances under study, together with those of a group of silicates and oxides, a Born–von Karman rigid-ion lattice-dynamical model has been applied to the whole Brillouin zone in calcite, aragonite (α- and β-CaCO3, respectively), magnesite (MgCO3) and dolomite [CaMg(CO3)2]. The Raman and IR spectra are satisfactorily reproduced and interpreted by these calculations; there is also very good agreement with atomic anisotropic displacement parameters (a.d.p.'s) derived from accurate crystal structure refinement by various authors and with the experimental values of thermodynamic functions over a wide range of temperatures. On these vibrational grounds, the stability of calcite with respect to aragonite at high temperature can be accounted for.

Theoretical Analysis of Flow Through Two-Dimensional Centrifugal Pump Impeller by Method of Singularities

1971 ◽  
Vol 93 (1) ◽  
pp. 35-40 ◽  
Author(s):  
S. K. Ayyubi ◽  
Y. V. N. Rao
Keyword(s):  
Centrifugal Pump ◽  
Operating Conditions ◽  
Two Dimensional ◽  
Pump Impeller ◽  
Pump Operation ◽  
Wide Range ◽  
Hydrodynamic Method ◽  
Flow Through ◽  
Experimental Values ◽  
Centrifugal Pump Impeller

The hydrodynamic method of singularities is used to analyze the flow through two-dimensional centrifugal pump impellers with blades of an arbitrary geometry. Computed values of ideal head are compared with experimental values obtained for a commercial pump. The agreement between theory and experiment is very close over a wide range of pump operation. The discrepancies that occur at other operating conditions are attributed to the effects of inlet passage and volute casing.

An Experimental Investigation on the Temperature Distribution in Circular Journal Bearings

1986 ◽  
Vol 108 (4) ◽  
pp. 621-626 ◽  
Author(s):  
Junichi Mitsui ◽  
Yukio Hori ◽  
Masato Tanaka
Keyword(s):  
Experimental Investigation ◽  
Angular Position ◽  
Journal Bearings ◽  
Operating Conditions ◽  
Test Rig ◽  
Clearance Ratio ◽  
Temperature Distributions ◽  
Wide Range ◽  
Lubricant Viscosity ◽  
Good Agreement

The temperature distributions in full circular bearings were measured in a test rig. The effects of journal speed, lubricant viscosity, and clearance ratio on the maximum bearing temperature and its location were discussed. The results were compared with the theoretical analysis by the present authors and good agreement was obtained over the wide range of operating conditions. The maximum bearing temperature is found to increase considerably with the increase of speed or lubricant viscosity and also with the decrease of clearance ratio. Its angular position is found to vary with speed and clearance ratio. These phenomena can be explained by the characteristics of maximum film temperature in the oil film.

scholarly journals Determination of physiochemical properties of Gum Arabic as a suitable binder in emulsion house paint

2016 ◽  
Vol 5 (1) ◽  
pp. 67-78
Author(s):  
Ali L. Yaumi ◽  
Ahmed M. Murtala ◽  
Habiba D. Muhd ◽  
Fatima M. Saleh
Keyword(s):  
Chemical Properties ◽  
Gum Arabic ◽  
Acacia Senegal ◽  
Physiochemical Properties ◽  
Binding Strength ◽  
Wide Range ◽  
Percentage Concentration ◽  
Physical And Chemical ◽  
Good Agreement

Gum Arabic “GA” is an organic adhesive produced from a tree called named Acacia Senegal. The gum has a wide range of industrial uses, especially in areas of feeds, textiles, and pharmaceuticals. It is used as emulsifier and serves mostly as stabilizer in both cosmetic and food products which contains oil water interface. GA sample was collected, formulated and prepared into various concentrations ranging from 20%w/v to 85%w/v. The quality and applicability of well characterized materials are directly related to their physical and chemical properties. From the physiochemical analysis, the result revealed that all the samples were slightly acidic (pH ranging from 4.81-6.41). This range is in good agreement with reported pH values for gum arabic and other Acacia gums by several authors. . The binding strength increases as the number of days increases for example in sample F (50%w/v) gum Arabic concentration increases from 1.5 in the 1st day to 1.97 in the 28th day. The samples prepared are denser than water which indicates that the density increases as the percentage concentration of the samples increases and the relative density of the gum solution is independent on time. The binding strength of sample G (75%w/v) gum concentration compared well to that of polyvinyl acetate (PVA). International Journal of Environment Vol. 5 (1) 2016,  pp: 67-78

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