Owing to the energy crisis and pollution problems of today, investigations have concentrated on
decreasing fuel consumption and on lowering the concentration of toxic components in combustion
products by using non-petroleum, renewable, sustainable and non-polluting fuels. While conventional energy sources such as natural gas, oil and coal are non-renewable, alcohol can be coupled to renewable and sustainable energy sources.
In this study, the combustion characteristics of diesel fuel and methanol blends were compared.
The tests were performed at steady state conditions in a four-cylinder DI diesel engine at full load at
1500-rpm engine speed. The experimental results showed that diesel methanol blends provided
12.7% inc
An experimental and numerical study has been carried out to investigate the heat transfer by natural convection and radiation in a two dimensional annulus enclosure filled with porous media (glass beads) between two horizontal concentric cylinders. The outer cylinders are of (100, 82 and70mm) outside diameters and the inner cylinder of 27 mm outside diameter with (or without) annular fins attached to it. Under steady state condition; the inner cylinder surface is maintained at a high temperature by applying a uniform heat flux and the outer cylinder surface at a low temperature inside a freezer. The experiments were carried out for an annulus filled with
glass beads at a range of modified Rayleigh number (4.9 ≤ Ra≤ 69), radiation
The role of the green areas lies in being one of the systems that plays the vital role in achieving the environmental dimension besides the socio-cultural body and the economic dimension in the hidden value of ecosystem services. However, many developing countries are characterized by a state of low community environmental awareness, which coincides with the basic need for land for housing and other uses, to take precedence over nature protection strategies. In the absence of clear planning and long-term planning strategies, all this led to abuses and violations of urban land use. In Iraq, the situation became more apparent due to the political, security and social conditions that followed the year 2003. Hence, the resea
... Show MoreThis research shows the experimental results of the bending moment in a flexible and rigid raft foundation rested on dense sandy soil with different embedded depth throughout 24 tests. A physical model of dimensions (200mm*200mm) and (320) mm in height was constructed with raft foundation of (10) mm thickness for flexible raft and (23) mm for rigid raft made of reinforced concrete. To imitate the seismic excitation shaking table skill was applied, the shaker was adjusted to three frequencies equal to (1Hz,2Hz, and 3Hz) and displacement magnitude of (13) mm, the foundation was located at four different embedment depths (0,0.25B = 50mm,0.5B = 100mm, and B = 200mm), where B is the raft width. Generally, the maximum bending
... Show MoreScheduling considered being one of the most fundamental and essential bases of the project management. Several methods are used for project scheduling such as CPM, PERT and GERT. Since too many uncertainties are involved in methods for estimating the duration and cost of activities, these methods lack the capability of modeling practical projects. Although schedules can be developed for construction projects at early stage, there is always a possibility for unexpected material or technical shortages during construction stage. The objective of this research is to build a fuzzy mathematical model including time cost tradeoff and resource constraints analysis to be applied concurrently. The proposed model has been formulated using fuzzy the
... Show MoreThis paper presents a numerical analysis using ANSYS finite element program to simulate the reinforced concrete slabs with spherical voids. Six full-scale one way bubbled slabs of (3000mm) length with rectangular cross-sectional area of (460mm) width and (150mm) depth are tested as simply supported under two-concentrated load. The results of the finite element model are presented and compared with the experimental data of the tested slabs. Material nonlinearities due to cracking and crushing of concrete and yielding of reinforcement are considered. The general behavior of the finite element models represented by the load-deflection curves at midspan, crack pattern, ultimate load, load-concrete strain curves and failure m
... Show MoreBank to turn (BTT) control is used to implement a command - to line of- sight (CLOS) guidance law. Physical description of the prineiples involved is given and a 10.th order nonlincar deterministic model proposed. Conventional control is used to design a closed loop controller for the nonlinear system
Continuous system simulation techniques are employed to explain the effect of bank turn on cross coupling of yaw, pitch and roll channels. Detailed simulation studies are then used for a wide range of engagement sinearieous for trajectory of Missile/ Target interception. The target model is considered for three cases: stationary, moving and maneuvering targets. Satisfactory results are bbtained for capturing the targets.
يتقصى البحث فهوم العمارة والتغير ضمن إطار علاقتهما ببعض من جهة وعلاقتهما من خلال الموضوع (المبنى) مع الذات المدركة (المتلقي) من جهة أخرى، وذلك لبيان أثر الإدراك المعرفي للمتلقي في تغيير النتاج المعماري، مع إيضاح فعل التغير المستمر الذي يقع على المبنى وما يترتب عليه من أثار وملامح تظهر في الشكل والمعنى، والتي تحدد لاحقا نوع التغير الحاصل خلال فترات الثبات النسبي من عمر المبنى، الذي يعتمد بدوره على ال
... Show MoreThe study introduces a theoretical analysis and numerical solution for the combustion of a hydrocarbon fuel droplet inside the combustion chamber. The study employs two mathematical models to analyze the combustion process. Conventional (Classical) model and Transient model. The combustion process of a stagnant droplet in the steady state was analyzed in the classical model, while, In the transient model, it was assumed that there is a period of time in the stages of the droplet combustion in which the droplet is heated before combustion. The effect of change in temperature on the thermo-physical properties of the fuel was adopted through the two models. For the classical model, a convenient approximation was adopted for the heat transfe
... Show MoreOne of the most important techniques for preparing nanoparticle material is Pulsed Laser Ablation in Liquid technique (PLAL). Carbon nanoparticles were prepared using PLAL, and the carbon target was immersed in Ultrapure water (UPW) then irradiated with Q-switched Nd:YAG laser (1064 nm) and six ns pulse duration. In this process, an Nd:YAG laser beam was focused near the carbon surface. Nanoparticles synthesized using laser irradiation were studied by observing the effects of varying incident laser pulse intensities (250, 500, 750, 1000) mJ on the particle size (20.52, 36.97, 48.72, and 61.53) nm, respectively. In addition, nanoparticles were characterized by means of the Atomic Force Microscopy (AFM) test, pH easurement
... Show MoreWater flow into unsaturated porous media is governed by the Richards’ partial differential equation expressing the mass conservation and Darcy’s laws. The Richards’ equation may be written in three forms,where the dependent variable is pressure head or moisture content, and the constitutive relationships between water content and pressure head allow for conversion of one form into the other. In the present paper, the “moisture-based" form of Richards’ equation is linearized by applying Kirchhoff’s transformation, which
combines the soil water diffusivity and soil water content. Then the similarity method is used to obtain the analytical solution of wetting front position. This exact solution is obtained by means of Lie’s
Removal of heavy metals from waste water has received a great deal of attention. The compare Cr
(VI) adsorption characteristics removing from wastewater by using thermally modified and non-modified
eggshells were examined
The behavior of forced convection heat transfer characteristics through and over porous layer near a
heated flat plate at variable temperature has been investigated numerically. Two cases of variable wall
temperature boundary condition are studied. The first case is of linear temperature variation with position
along the flat plate and the second case is of sinusoidal temperature variation with time of heating. The flow field in the porous region is governed by the Darcy-Brinkman-Forchheimer equation, the thermal field in the porous region by the energy equation and the part over the porous matrix includes flow and heat transfer equations. Solutions of the problem have been carried out using a finite difference method through th
This research attempts to trace the most significant development caused by the information revolution, namely "the Communication Technology" which reduced the distances between different urban communities, or within a single one, eliminated the geographical boundaries and the transformed the world into a global village. This led to the emergence of new forms and bodies to those urban communities; perhaps the most important is the fragmentation of the major cities and the emergence of (Satellite Cities) with global links, rather than hinterlands to the local capital cities as in the past. But in spite of the technological tide of communications and its inevitable impacts, it stays, with all its possibilities, a reaction that occurs only i
... Show MoreThis paper is a study of the effect of natural saliva (oral cavity) and a fluoride mouthwash on dental
amalgams .Two types electrodes were made the first was of a high copper amalgam while the second was
made from a low copper amalgam. They were immersed in two types of electrolytes for twelve hours and the whole galvanic cell was connected to a computer via a potentiosat. Their corrosion currents, corrosion
voltage and corrosion resistance was recorded and compared to find which medium that is usually has the
most severe effect on the amalgams corrosion.
This study focused on treating wastewater to remove phosphorus by adsorption onto natural
and local materials. Burned kaolin, porcelinite, bauxite and limestone were selected to be tested
as adsorption materials.The adsorption isotherms were evaluated by batch experiments, studying
the effects of pH, temperature and initial phosphorus concentration. The results showed that at pH
6, temperature 20°C and 300 mg/l initial phosphorus concentration; the sorption capacity was
0.61, 9, 10 and 13 mg/g at 10 h contact time, for burned kaolin, porcelanite, limestone and bauxite
respectively. As the pH increased from 2 to 10 the removal efficiency for the materials differs in
behaviour. The removal efficiency increased from 40
The present study deals with the optimum design of self supporting steel communication towers. A special technique is used to represent the tower as an equivalent hollow tapered beam with variable cross section. Then this method is employed to find the best layout of the tower among prespecified configurations. The formulation of the problem is applied to four types of tower layout
with K and X brace, with equal and unequal panels. The objective function is the total weight of the tower. The variables are the base and the top dimensions, the number of panels for the tower and member's cross section areas. The formulations of design constraints are based on the requirements of EIA and ANSI codes for allowable stresses in the members
يعتمد جزء من تطور المجتمعات على مدى قدرتها وقابليتها على التلاؤم مع التغيرات اللازمة والمستمرة لتطوير استجابتها مع البيئة المناخية
المحيطة بها، وقد كان للتطور التكنولوجي الأثر المباشر على هذا المفهوم وأهمية توجيهه بالإتجاه الصحيح لأبنيتنا وبصورة تتواءم مع المتغيرات
المناخية المحلية.
ونظرًا لقلة الدراسات التي تركز على أهمية تكاملية البيئة المناخية مع التكنولوجيا المعاصرة وبما ينسجم مع الواقع المحل
Process capability provides a quantitative measure for gasoline production conformance to specifications.It was measured throughout four consecutive months of the last quarter of 2011. Results revealed high percentages (up to 44%) of non conforming gasoline blends to Iraqi marketing specifications for petroleum products (2000) by inspecting 122 different samples of Iraqi regular gasoline (RON 85).
Quality cost analysis as an important financial control tool was carried out to evaluate Cost of Quality (COQ) which was large due to non conforming gasoline reached up to (722.8 M.ID) in October. In this research COQ was investigated in order to identify the opportunities of gasoline quality improvements through production process. Also cus
Experimental programs based test results has been used as a means to find out the response of individual elements of structure. In the present study involves investigated behavior of five reinforced concrete deep beams of dimension (length 1200 x height 300 x width150mm) under two points concentrated load with shear span to depth ratio of (1.52), four of these beams with hallow core and
retrofit with carbon fiber reinforced polymer CFRP (with single or double or sides Strips). Two shapes of hallow are investigated (circle and square section) to evaluated the response of beams in case experimental behavior. Test on simply supported beam was performed in the laboratory & loaddeflection, strain of concrete data and crack pattern of
Generally, direct measurement of soil compression index (Cc) is expensive and time-consuming. To save time and effort, indirect methods to obtain Cc may be an inexpensive option. Usually, the indirect methods are based on a correlation between some easier measuring descriptive variables such as liquid limit, soil density, and natural water content. This study used the ANFIS and regression methods to obtain Cc indirectly. To achieve the aim of this investigation, 177 undisturbed samples were collected from the cohesive soil in Sulaymaniyah Governorate in Iraq. Results of this study indicated that ANFIS models over-performed the Regression method in estimating Cc with R2 of 0.66 and 0.48 for both ANFIS and Regre
... Show Moresensor sampling rate (SSR) may be an effective and crucial field in networked control systems. Changing sensor sampling period after designing the networked control system is a critical matter for the stability of the system. In this article, a wireless networked control system with multi-rate sensor sampling is proposed to control the temperature of a multi-zone greenhouse. Here, a behavior based Mamdany fuzzy system is used in three approaches, first is to design the fuzzy temperature controller, second is to design a fuzzy gain selector and third is to design a fuzzy error handler. The main approach of the control system design is to control the input gain of the fuzzy temperature controller depending on the cur
... Show MoreFao region is characterized by weak soft silty clay to clayey silt thick layer which extends to a depth of about 20 m. The construction of some structures on such soils may needs piles. During the installation of driven piles, the soil geotechnical properties are exposed to significant changes result due to shearing under large shear strains. These changes significantly decrease the shear strength of the virgin soil due to the destruction of soil structure caused by remolding. The degradation of shear strength is usually followed by strength regaining which is called “Thixotropy”. In this study, the thixotropic effect on Fao clay was investigated. Many disturbed and undisturbed soil samples were brought from Fao regi
... Show MoreThree revolutions characterize the age of information: Information Revolution,Technology Revolution and Media Revolution. These revolutions developed and interacted with each other in an amazing way. Way to an extent that it becomes a title to our
contemporary architecture. These revolutions changed people‟s thoughts, behaviors, and traditions. The effect of technology on the urban structure generally and the urban space specifically changed the physical structure of these spaces as a necessary result to the change of intellectual structure in community. The information revolution changed a lot of the common urban space„s characteristics and concepts as well as an extreme change in concepts related to the space.
The new though
The verse (35) in SURA (AL- Nur) in the HOLY QURAN has inspired the author to look into the possibility of using Olive Oil as active dye laser material. Olive Oil which is classified as organic compound, having a good properties candidate it to be used as active dye laser material. The emission spectrum diagrams at some of absorption peaks (414, 536, 632 and 670) nm will be measured. These diagrams have been used to determine the Fluorescence quantum yield, Oscillator strength, Einstein coefficients for the spontaneous emission, Radiative and Fluorescence lifetime and absorption and cross sections. It has been found that fluorescence occurs at 669 nm for the entire absorption spectrum. Fluorescence of Olive Oil has been experimented usin
... Show MoreThe present work is concerned with the theoretical and experimental investigation of flow pattern of Newtonian fluid in liquid mixing process in stirred tank with flat blade impeller. A threedimensional model for mixing process was simulated. The effected parameters are rotation speed and impeller diameter. Continuity, momentum, and turbulent equations were solved by ANSYS package software 5.4 code with FLOTRAN/CFD based on Finite Element method. In the experimental work, two visualization methods are used in this work, the first method is the acidbase reaction visualization method and the second is the particle distribution visualization method.
Different chemical materials were used in the first method, NaOH as a base, 2 4 H SO as a
This paper describes a numerical study of natural convection heat transfer and fluid flow characteristics inside a cavity with wavy vertical walls. The bottom wall is heated by spatially varying temperature and other three walls are kept at cooled temperature. Governing equation was discretized using the finite volume-method with staggered variables arrangement in curvilinear coordinates. Two geometrical configurations were used in this study for symmetrical and unsymmetrical wavy vertical walls (total of 132 cases) for range of Ra=100 to 106 and fixed Prandtl number (0.71). The effects of the wave geometry, wave amplitude, number of undulation, and Rayliegh number on flow behavior, thermal field, local Nusselt number and Nusselt number
... Show MoreThe hydrodynamic and thermal boundary layers have great effect on the fluid flow and heat transfer between rotating turbine blade. In the present work, the flow and heat transfer is analyzed numerically by solving two dimensional incompressible boundary layer equations. A ( k – ε ) turbulence modeling is used to obtain the eddy viscosity. The finite volume method is introduced to carryout all computational solution with staggered grid arrangement. Due to complex physical domain the original coordinate system is transferred to non orthogonal coordinate system. The calculation of present work done for rotating two dimensional turbine cascade with different rotating speeds (1500 rad/s, 1800 rad/s, 1900 rad/s), and for different Reynolds
... Show MoreSmart water flooding (low salinity water flooding) was mainly invested in a sandstone reservoir. The main reasons for using low salinity water flooding are; to improve oil recovery and to give a support for the reservoir pressure.
In this study, two core plugs of sandstone were used with different permeability from south of Iraq to explain the effect of water injection with different ions concentration on the oil recovery. Water types that have been used are formation water, seawater, modified low salinity water, and deionized water.
The effects of water salinity, the flow rate of water injected, and the permeability of core plugs have been studied in order to summarize the best conditions of low salinity
... Show MoreThis research examines the use of vibratory treatments to reduce residual stresses in small welded parts. In this experimental investigation, a post weld vibration treatment was applied to T- A106 steel pipe fitting specimens to study the effect of the treatment on the residual stress and the hardness of the material. The vibratory stress relief treatment was carried out at different vibration frequency. The results have demonstrated that post-weld vibratory stress relief of small size fittings is possible and residual stress may be relieved, and the treatment may be an alternative method for heat treatment especially when unchange in dimensions and material stability are required.