Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : modeling


Composition Design Modeling and Experimental Verification of (Co Ni Al) Shape Memory Alloys

M.N. Arbilei

Engineering and Technology Journal, 2018, Volume 36, Issue 1, Pages 84-88

The most important concepts to apply a shape memory alloy in many
industrial applications is the composition design that controls the
transformation temperatures. In this paper, two mathematical models were
created to predict the transformation temperatures for poly-crystalline (Co-Ni-
Al) alloys. The data that was depend on to find the relation between chemical
composition and transformation temperatures were concluded from previous
work and approved by preparing samples in investigation practically. Four
different alloys were prepared to verify this relation. It was indicated that the
best criteria that present the chemical composition is the (e/a) and make the
alloy applicable for different applications. These suggested chemical
compounds could be controlled and adjusted according to heat treatment time.

Theoretical Study of the Effective Parameters for Direct Contact Membrane Distillation in Hollow Fiber Modules

Salah S. Ibrahim

Engineering and Technology Journal, 2014, Volume 32, Issue 12, Pages 2949-2969

The main object of this research is to study the parameters that have important effects upon performance of the direct contact membrane distillation (DCMD) process, through predicting the effects of the outside and inside diameters, the thickness of the hollow fiber membrane, the pore size, porosity, tortuosity, module length, number of fibers in module, inlet feed temperature, inlet feed concentration, inlet permeate temperature and the velocity of feed and permeate. The effective parameters that influence the performance of DCMD are classified into membrane characteristics, operating conditions, and parameters of module specifications. This study is based on an experimental system of Wang et al., 2008 [1] as typical system.It was found that theincreaseof the permeate fluxis by selecting an optimum thickness for each inside or outside diameter of hollow fibers and anoptimum number of fibers in the module and increasing the porosity and pore size within practical range and decreasing of tortusity andas well as increasing the inlet feed temperature rather than decreasing the inlet permeate temperature for constant temperature difference between feed and permeate. Also it is found that the feed concentration and fiber length play an inverse role with the permeate flux.

Modeling of Arc Metal Welding Process of Low Carbon Steel (304)

Majid Hameed Abdul Majeed

Engineering and Technology Journal, 2014, Volume 32, Issue 3, Pages 643-652

This work includes an investigation of the effect and optimization of welding parameters on the tensile strength in the arc metal welding process. The experimental studies were conducted under varying welding currents, wire diameters, and heat input. The settings of welding parameters were determined by using the Taguchi experimental design method. The level of importance of the welding parameters on the tensile strength is determined by using analysis of variance (ANOVA). The optimum welding parameter combination was obtained by using the analysis of signal-to-noise (S/N) ratio. The tensile strength model was formulated based on Analysis of Variance (ANOVA) using Minitab® statistical package. The experimental results confirmed the validity of the used Taguchi method for enhancing the welding performance and optimizing the welding parameters in the arc metal welding process.

A modeling comparison studies for thermo-mechanical and other Properties of RHDPE and RLDPE Wastes

Falak O. Abas; Raghad U.Abass; Mohammed O.Abass

Engineering and Technology Journal, 2014, Volume 32, Issue 3, Pages 681-701

A recycled waste plastic (recycled high density poly ethylene RHDPE and recycled low density poly ethylene RLDPE) are exposed to environmental conditions during the usage for many years ago. Also the chemical contaminants in the internal composition had effects on the thermo-mechanical and other properties for these wastes.
Then weathering effect data are examine for both locally and international wastes on their thermo-mechanical and chemical properties such as (Tensile strength, modulus, elongation, impact and permeability) respectively.
Afterward different mathematical software models are applied to analysis these weathering – properties data in order to estimate the more effective properties that changed by these weathering conditions such as (concentration of contaminant, time, temperature, thickness of specimen, length of spectra, basic property).
The results shows that a multi-polynomial model has a best fit for most or several of properties to active weathering variables, also gave a vary residual and deviation than experimental analyzed data for both sources of wastes local and international RHDPE and RLDPE. Also results of thermo-mechanical and chemical properties prove that both tensile strength and modulus of elasticity thermo-mechanical properties and permeability / length of spectra chemical property were given a high quality of correction and fitting factor from 93-99 %, with less deviation and residual function was produced. And analyzed weathering properties of RHDPE gave a best fit than RLDPE; all of them fitted the mathematical software model below:

…(1)

Where:
a, b, c …J = coefficient of the best fit model.
x1 = concentration of contaminants.
x2 = time of aging.

Modeling the Behavior of Frost Growth on Finned Tube Heat Exchanger

Zainab Hasoun H.Naji

Engineering and Technology Journal, 2014, Volume 32, Issue 1, Pages 215-229

A quasi-steady finite-volume model was developed for modeling a plain-finround-tube heat exchanger under frosted conditions. In this study, the heat and mass transfer characteristics of heat exchangers during frost formation process are analyzed numerically. Unsteady heat and mass transfer coefficients of the air side, heat transfer coefficient of the refrigerant side, frost layer thickness, the surface efficiency of the
heat exchanger and the mass flow rate of the frost accumulated on the heat exchanger surface are calculated. The total conductivity (UA) and pressure drop of the heat exchanger are reported for different air inlet and refrigerant temperature. Results have shown that frost layer growth is faster with lower inlet air temperature. Using the developed mathematical model, the algorithm and the computer code, which have
been experimentally validated, it is possible to predict a decrease of exchanged heat flux in the heat exchanger under frost growth conditions. The model could be further extended to simulate direct expansion evaporators with varying operating conditions and variable heat exchanger geometry.

Shear Wall Analysis using Framework Method: Comparison with Shell Element Method and Column Analogy

Ammar A. Ali; Hassan H. Jony

Engineering and Technology Journal, 2013, Volume 31, Issue 10, Pages 1949-1961

Different techniques are utilized to analyze shear walls like shell elements model or column analogy. Framework method (FWM) is used to substitute the shell elements. A rectangular model of rigidly-connected plane framework is adopted here. FWM is found to be more sensitive for mesh size than shell element. Column analogy (CA) is to model the shear wall using the standard wide column analogy between the adjoining columns using beam elements. The column analogy is a simple and efficient method to represent the structure.

Thermal Radiation Detector (TRD) Modeling

Mehdi Munshid Shellal

Engineering and Technology Journal, 2011, Volume 29, Issue 2, Pages 322-335

This paper describes the theoretical principles of TRD operation based on
thermal absorption of incident power of radiation. In the modelling procedures,
the main parameters influencing on the detector features have been introduced. So
the this model allow us to predict the behaviour of different types of thermal
detectors. It is found that the temperature response of the detector against the
frequency of incident radiation in logarithmic scale describes the TRD as a typical
low pass filter characteristics. The cut off corner frequency is found to be at 1 Hz
under which the temperature change attains a saturation value. In the sense that the
thermal detector will detect all the incoming radiations of higher frequency.

Modeling and Simulation of Flue Gas Desulfurization Using Slurry of Fine Activated Carbon Particles

Asmaa I. Eliass; Neran K. Ibrahim

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2294-2307

The main objective of the present work is to investigate the
feasibility of using a slurry of fine activated carbon particles,
dp<1mm, in a fixed bed reactor for the removal of sulfur dioxide
from simulated flue gas (air, SO2) stream. A mathematical model
governing the desulfurization process was proposed. The partial
differential equations which describe the adsorption of SO2 from a
moving gas stream to the sorbent bed were solved using a finite
difference method. The kinetic parameters of the mathematical
model were obtained from a series of experimental desulfurization
runs carried out at isothermal conditions and different operating
conditions; bed temperature (333K-373K), initial SO2 concentration
(500ppm-2000ppm) and static bed height (10cm-24cm). The results
showed that the use of fine activated carbon particles improved the
removal efficiency to about 97%. The verification of the simulation
and experimental results showed that the proposed model gave a
good description of the desulfurization process with 95% confidence
level

Modeling of Single Channel Monolithic Reactor with The Single pass Flow Operation System

Lange; Zaidoon; A Al-Najar; Jenan; Adel; A. Shuhaib

Engineering and Technology Journal, 2010, Volume 28, Issue 11, Pages 2221-2236

In the following sections, the recent published studies on modeling and
simulation of monolith reactors were reviewed. Mass transfer, and reaction kinetics
were achieved by establishing mass, energy and momentum balance equations. The
model equations were solved simultaneously. Such a model can be useful for studying
the impact of changes of superficial gas and liquid velocities on reaction rate within
the slug flow regime. The reaction system used is the hydrogenation α–methyl styrene
(AMS) to cumene over a palladium on γ–alumina catalyst, It is a well known
system used to understand three-phase reactor performance under mass transfer
limited condition by the gas mass transfer through the liquid film at the catalyst
surface to the active sites. The effects of superficial gas and liquid velocities on
reaction rate were studied with the range of 10 cm/s ≤ UL ≤ 30 cm/s, and 10 cm/s
≤ UG ≤ 30 cm/s. The flow pattern for all these range of velocities was in the Taylor
flow pattern.

A Dynamic Modeling Capability for Subcritical Vapor Compression Refrigeration System

Jafar M. Hassan; Ali H. Tarrad; Mohammed N. Abdullah

Engineering and Technology Journal, 2009, Volume 27, Issue 13, Pages 2319-2338

In this investigation the individual component models for a typical subcritical cycle are developed based on the best published theoretical and empirical literature. The developed approach, especially for air conditioning systems, is conceptually new and can be used with modification to a variety of multicomponent system applications. The component models are then integrated and the model predictions validated against the data from various experimental test systems.
A variable speed compressor test rig was used to obtain the experimental data to be compared with the results predicted from the system model. The experimental data was monitored from the start-up of the system until the achievement of its steady-state. The system approached its steady-state after 270 sec and 360 sec for compressor speeds of 900 rpm and 1200 rpm respectively. The system disturbance was imposed by changing the operation conditions for each component. A comparison between the experimental data for these disturbances and theoretical results shows a good agreement with a discrepancy of
about (5%). The model can be used as a basis for the design, performance and efficiency of a vapor compression systems.

Effect of Dual Reinforcement on Wear Resistance by Aluminum Compacts Reinforce by SiC, Al2O3

Mohammed Moanes Ezzaldean Ali; Hanan A. R. Akkar; A. K. M. AL-Shaikhli; Ali K. Shayyish; Muhsin J. Jweeg; Wisam Auday Hussain; Mohammed T. Hussein; Mohammad A. Al-Neami; Farah S. Al-Jabary; Jafar M. Hassan; Ali H. Tarrad; Mohammed N. Abdullah; Ahmed T. Mahdi; Eyad K. Sayhood; Husain M. Husain; Nidaa F. Hassan; Rehab F. Hassan; Akbas E. Ali; Assim H Yousif; Kassim K Abbas; Aqeel M Jary; Shakir A. Salih; Ali T. Jasim; Ammar A. Ali; Hosham Salim; JafarM. Daif; Ali H. Al Aboodi; Ammar S. Dawood; Sarmad A. Abbas; Salah Mahdi Saleh; Roshen T. Ahmed; Aseel B. Al-Zubaidi; Mohammed Y. Hassan; Majid A. Oleiwi; Shaimaa Mahmood Mahdy; Husain M. Husain; Mohammed J. Hamood; Shaima; a Tariq Sakin

Engineering and Technology Journal, 2009, Volume 27, Issue 13, Pages 423-429

The producing composite materials of dual reinforcement in which the matrix material is aluminum reinforced with two types of ceramic particles : which are Alumina (50μm

Keywords

composite materials; wear test ; Al2O3; SiC: Al

Fusion Face and Palmprint for Human Recognition via Spectral Eigenvector

Hana; a M. Salman

Engineering and Technology Journal, 2009, Volume 27, Issue 4, Pages 787-798

The Biometrics recognition systems act as an efficient method with broad
applications in the area of: security access control, personal identification to humancomputer
communication. From other hand, some biometrics have only little variation
over the population, have large intra-variability over time, or/and are not present in all
the population. To fill these gaps, a use of multimodal biometrics is a first choice
solution [1].
This paper describes a multibiometrics method for human recognition based on
new teacher vector identified as spectrum eigenface, and spectrum eigenpalm. The
proposed combination scheme exploits parallel mode capabilities of the fusion feature
vectors in matching level and invokes certain normalization techniques that increase its
robustness to variations in geometry and illumination for face and palmprint. The
correlation distance is used as a similarity measure. A threshold value is used to
prevent the imposter for being recognized. Experimental results demonstrate the
effectiveness of the new method compared to the unimodal biometrics for spectrum
eigenface/eigenpalm.

Modeling Time to Corrosion Initiation in High-Performance Ferrocement Exposed to Chlorides Environments

J. Forth; Maan S. Hassan; S. A. Salih

Engineering and Technology Journal, 2009, Volume 27, Issue 1, Pages 18-31

The applications of a mineral admixture, or a zinc coating to steel surface, or a
combination of both are methods used for the corrosion prevention of ferrocement
element in this study. Results of a study to evaluate many corrosion protection systems
with metakaolin and/or galvanized steel mesh are presented in six U-shaped specimens.
Specimens were built to simulate exposure conditions typical for marine environment.
Laboratory data collected along duration of 40 weeks of exposure were used in
modeling the cover depth as a function of time to corrosion initiation of the investigated
corrosion prevention methods. Methods used to assess the condition of specimens
included chloride concentration measurements, and corrosion rates. Model predictions
show that the ferrocement specimen of high-performance mortar with metakaolin
provides much better level of protection against moisture and chlorides than the
conventional specimen, by delay rate of chloride ingress. Application of a galvanized
steel mesh causes an elevation of the chloride threshold resulting in an additional
increase in the predicted time to corrosion initiation.

Sulfur Dioxide Removal in Coal Slurry Reactor

Neran K. Ibrahim; Zainab A. Jawad

Engineering and Technology Journal, 2008, Volume 26, Issue 4, Pages 462-477

The objective of this work was to study the feasibility of using coal
slurry for the removal of SO2 from simulated flue gas stream (air,
SO2). The effect of gas rate, temperature, and initial SO2
concentration on the overall removal efficiency was investigated at
wet and dry bed conditions. The results indicated that the optimum
gas rate was 60 l /min. The SO2 removal efficiency was highly
temperature sensitive, and increases with increasing the bed
temperature especially at wet bed conditions and decreases with
increasing SO2 initial concentration. A mathematical model for the
desulfurization process was proposed based on the material balance
for gaseous and solid phase streams. The model was found to give a
very good description of the experimental data with 95% confidence
level.