About Journal

The Tikrit Journal for Engineering Sciences is not limited to a specific aspect of science and engineering but is instead devoted to a wide range of subfields in the engineering sciences. While it encourages a broad spectrum of contribution in the engineering sciences, its core interest lies in issues concerning material modeling and response. Articles of interdisciplinary nature are particularly welcome. The primary goal of the new editors is to maintain high quality of publications. There will be a commitment to expediting the time taken for the publication of the papers. The articles that are...
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Journal Information

Publisher: Tikrit University

Email:  tahseen@tu.edu.iq

Editor-in-chief: Professor Dr. Aziz Ibrahim Abdulla

Print ISSN: 1813-162X

Online ISSN: 2312-7589

Application of Dynamic Cone Penetration Test to Gypseous Soils

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 1-5

Dynamic cone penetration test (DCPT) is a fast, economical and easy to conduct. It is widely used to assess the strength of natural and compacted soils. The device is introduced in the 1950s. However, it was newly introduced in Iraq. This study aims to evaluate the potentials of DCP in geotechnical explorations in the gypseous
soil since it covers a large area of the country and to obtain correlations with the California bearing ratios (CBR) and investigating the effect of gypsum on the CBRDCP relationship. Field and Laboratory tests were conducted on soil sample retrieved from six sites with different gypsum contents (28-41) %. Laboratory tests
include performing CBR and DCP tests in a cylindrical mold. A statistical analysis of the results shows that gypsum content is an affecting factor on DCP and good CBR-DCP correlations on gypsum content were obtained..

Optimum Building Wall Thickness under Actual Weather Conditions for Kirkuk City

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 11-15

The aim of the present study is to obtain the optimum wall thickness of the buildings from four different wall thickness sizes that which selected as 48, 32, 24, and 16 cm used for building room. The dimension of 6×4×3 m, built by a common brick insulated for all sides except south wall. For this purpose, an energy simulation has been conducted by preparing a computer programmer and was executed by Matlab software. The two days in different weather conditions on 2016, first on 30/12, and other 01/07 for a constant indoor temperature at 23oC. The results showed that the inner surface temperature was more stability against to the weather change for both climate conditions. In addition, the thick wall 48cm needs more
energy consumption than other three types of walls about twice that 16cm thickness in a cold climate. The wall thick was more active for energy saving in a hot climate, and obverse, where the thin wall has more energy saving in a cold climate. The energy analyzing for both climates showing that the optimum wall thickness about 30 cm and the rate of energy consumption were estimated about 500 W..

Effect of Fluidized Bed Particle Size on Heat Transfer Coefficient at Different Operating Conditions

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 24-29

The aim of this study is to investigate the effect of gas flow velocity, size of sand particles, and the distance between tubes immersed in a fluidized bed on heat transfer coefficient. Experimental tests were conducted on a bundle of copper tubes of (12.5 mm) diameter and (320 mm) length arranged in a matrix (17×9) and immersed in a fluidized bed inside a plastic container. One of the tubes was used as a hot tube with a capacity of (122 W). (25 kg) of sand with three different diameters of sand particles (0.15, 0.3 and 0.6 mm) was used in these tests at ten speeds for gas flow (from 0.16 m/s to 0.516 m/s). The results showed a significant inverse effect of fluidized bed particles diameter on the heat transfer coefficient. Accordingly, the heat transfer coefficient for (0.15mm) diameter sand was found to be higher than that of (0.3 mm) and (0.6 mm) sand by about (3.124) and (6.868) times respectively, in all tests. The results showed good agreement with results from other studies conducted under the same conditions but with different sand
particle size..

Flexural Behavior of Reinforced Concrete One-Way Slabs with Different Ratios of Lightweight Coarse Aggregate

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 37-45

The aim of the present research includes an experimental investigation of flexural behavior of lightweight reinforced concrete one-way slabs with different ratios of course aggregate. Nine lightweight reinforced concrete one- way slabs incorporated by two types of lightweight course aggregate were tested in these
investigation. Also the mechanical properties and workability test for concrete used in the study. There was chosen eight concrete mixes were casted by replacing the normal coarse aggregate by lightweight course aggregate; claystone (bonza) and thermostone. Different percentage of aggregate replaced were done (25, 50, 75 and
100) %, in addition to the reference mix of (0%) replacement ratio was casted. For each concrete mix: Three cylinders for compressive strength and density of saturated and dry surface concrete tests, three cylinders for splitting tensile strength test and three prisms for modulus of rupture test were prepared. Also for each mix was casted, prepare a one slab specimen for bending moment test for all mixes contain a light coarse aggregate and reference mix. The main results of mechanical properties are ((38.44-12.38), (3.969-2.172) and (10.467-3.194)) MPa, for compressive, splitting and flexural strength respectively with differences of (67.79, 45.12 and 69.48) % respectively compared with the reference mix. Also the flexural capacities of the lightweight concrete slabs that contained a different ratios of light coarse aggregate (0.028 and 0.026) MPa were recorded with (22.5 and 28.62) % compared with reference sample of 0.035 MPa. )035.0 )MPa.

Tensile Strength, Micro-hardness and Microstructure of Friction-Stir-Welding AA6061-T4 Joints

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 51-56

Welding of aluminum alloys by traditional welding methods creates some defects such as hot cracks, porosity, and void that led to decreasing of mechanical properties. Friction Stir Welding (FSW) gives good mechanical properties of aluminum alloy welds. In this paper, FSW worked in 4 mm thick plate of 6061-T4 aluminum alloy, with two welding parameters are used (tool rotational speed and feed rate) was investigated, were analyzed the microstructure and mechanical properties by carried out microstructural, microhardness, and tensile strength tests. From results are found defect-free of welds at a wide range of parameters. Stir zone shows a fine-equiaxed grain and high hardness, not significantly change between heat affected zone and base metal in size grain. Tensile strength of welds was lower than base metal and fracture location was occurred at a low hardness region for the welds.لحام سبائك االلمنيوم بالطرق التقليدية يخلق بعض العيوب مثل الشقوق الحارة والمسامية والفراغات التي تعمل على خفض الخواص الميكانيكية للملحومات، لحام الخلط االحتكاكي يعطي خواص ميكانيكية جيدة لملحومات سبائك االلمنيوم. في هذا البحث دراسة للحام سبائك االلمنيوم (T4-AA6061) بسمك (4mm) بوساطة لحام الخلط االحتكاكي تحت متغيرات) السرعة الدورانية ومعدل التغذية(، وحللت الخواص الميكانيكية والبنية المجهرية من خالل اجراء فحوصات البنية المجهرية والصالدة المجهرية ومقاومة الشد. من خالل النتائج وجد ان البنية المجهرية لمنطقة الخلط ذات حجم حبيبي ناعم-ومتساوية المحاور وذات صالدة عالية وليس هناك اختالف مميز في الحجم الحبيبي بين منطقة المعدن األساس والمنطقة المتأثرة بالحرارة، مقاومة الشد للملحومات أدنى من مقاومة الشد للمعدن األساس وموقع الكسر للملحومات حدث في منطقة
الصالدة المنخفضة.

The Effect of Pads Number and Their Tilt Angles on the Bearing Stiffness

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 6-10

In this work a plain (conventional) and a tilted bad bearings are analyzed and studied (both have the same dimensions and work conditions). Three, four and five pads models are studied. The pads are fixed circumferentially in a manner each two close pads are separated with an angle that is the same for all the close pads.
Each pad is pivoted in its trailing edge and is facilitated to be tilted around this pivot with small angles. This study was achieved for three values of tilting angles. These angles are, 0.01o, 0.011o and 0.012o. Two dimensions' form of Reynolds equation is used and solved numerically then the stiffness coefficients had been calculated. A comparison had been done between the stiffness coefficients values for the two models (tilted pads and conventional bearings). The results of this comparison was found that (for n = 0.4), are, +28%, +275%, +270 % and -100% for Ksr, Krr, Kss and Krs respectively. It was noticed that the values of the principal coefficients Krr and Kss are increased significantly while the cross coupling coefficient, (Krs) is decreased significantly and (Ksr) is increased slightly. And this is a positive sign for stability improvement. Also it was found that increasing the tilt angle (delta) cause an increase of the stiffness coefficients values. These increases (for n = 0.4 and changing the tilt angle from 0.010 to 0.011 then to 0.012 respectively) are, Krr=+50%, +47%, Kss = +40%, +32%, Ksr = +33%, +42%, and Krs = +15%, +20%. And since increasing the values of the cross coupling coefficients make the bearing stability worse, so increasing the tilt angle is not a
preferable method for improving stability. Changing the number of pads is a better solution and it was found that three pads bearing is the best among them..

Effects of Rice Husk Ash–Magnesium Oxide Addition on Wear Behavior of Aluminum Alloy Matrix Hybrid Composites

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 16-23

A336.0 aluminum alloy used to fabricate hybrid composites using rice husk ash (RHA) and MgO particles as reinforcement. The influence of the particles on the wear behavior of A336.0 aluminum alloy as a matrix that reinforced with MgO and RHA was investigated. Firstly, the rice husk burned at 700°C and then heat treated at 1100°C for 2 hrs. The ash characterized by X-ray florescence and X-ray diffraction. Less than 53 and 125 micron are the particle sizes of MgO and RHA respectively. The hybrid composites manufactured using stir casting method in two steps. A336.0 aluminum alloy reinforced with 4:0, 3:1, 2:2, 1:3 and 0:4 of RHA: MgO with 10 wt% total reinforcement phase. Optical microscope and X-ray diffraction were used to characterize the prepared hybrid composites. Dry sliding
wear, hardness, apparent density, percentage of porosity and coefficient of friction were examined. Results indicated that porosity, apparent density and hardness enhanced with increasing MgO, while increasing wt% of RHA decreased the apparent density. Results indicated that with inceasing the applied load the wear
rate of the composites was enhanced. Coefficient of friction varies inversely with applied load and wt% of RHA. Hardness increased with increasing RHA while the friction coefficient and the wear rate decreased. The minimum wear rates were at 10% RHA and Al-alloy-(RHA-MgO) [3:1] composites, while the minimum friction coefficients were at 10% RHA composites. 10%RHA.

Effecting of Steel Fibers and Fly Ash on the Properties of Concrete

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 30-36

In this research, the effect of the addition of fly ash particles with different weight ratios of 15%, 20%, and 25% as well as the addition steel fibers with different volume fractions of 0.25%, 0.75%, and 1.25% on the mechanical properties of concrete (compressive strength and modulus of rupture) was studied. To carry out this research, ten concrete mixes were prepared, one of which is the reference normal concrete (without any additives), the others contain steel fibers and fly ash as additives with the mentioned volumetric and weight proportions. For each type of concrete mix, three standard 150×300 mm cylinders and three standard prisms
100×100×500 mm were casted, water to cementing material ratio was fixed for all concrete mixes (W/cm = 0.435) and the superplasticizer was used with ratio of 0.98%-1.22% by weight of the cementitious material in mixtures that contain steel fibers and fly ash particles as a partial replacement of cement weight. The results showed that the addition of fly ash particles had little effect on the mechanical properties of normal concrete, while the steel fibers had the greatest effect. The highest increase in compressive strength and flexural strength compared with reference concrete was 61.60% and 78.84%, respectively in the volume fractions 1.25% of steel fiber..

Effect of Colored Filters on PV Panels Temperature and Performance under Baghdad Meteorological Condition

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 46-50

In this work, the influence of colors of filters upon the photovoltaic panels rising temperature and electrical performance was studied under Baghdad Meteorological Condition. Basing on the energy analysis of a photovoltaic solar system and by using the photonic theory, the available energy on the PV plane system has been evaluated. Seven colored filters each with (85W) PV modules were used in this case study, to reveal the impact of colored filters upon the electrical productivity of PV panel with the variation in the temperature caused by these filters. There is the
main issue of this work is to show how the performance of PV module by imposing colored filter and hence how and to how much improve it by reducing the cell temperature in hot climate. Outcomes showed that the PV technology is affected by the color filters. In other words, red filter gives light have least photons energy, and violet filter gives light have the most photons energy and green is between the two. So, red colors filter gives highest PV panel temperature comparative with others filters, while violet color filter was the lowest. PV module with the lowest temperature colored filter gives the best electrical performance than others..

Control Techniques of Torque Ripple Minimization for Induction Motor

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 57-63

A Matlab-Simulink environment used to build a model of an Induction Motor (IM) to study and explore methods for minimizing the torque ripple. Various control strategies were reviewed and simulation studies were carried out for the following control methods: Direct Torque control, Direct Torque control with harmonic elimination, and Direct Torque control with Matrix convertor were the obtained results analyzed, evaluated, and compared to each other. The simulation results confirmed that Using Direct Torque Control with Harmonic elimination method was significantly minimized the torque ripple as the harmonics of the output voltage were canceled; discussions and conclusions were presented in this study..

Study the Effect of Rotational Speed and Pouring Temperature on the Wear Resistance and Hardness of Alloy (A380) Reinforced with Different Volume Fraction of Alumina Particles

Tikrit Journal of Engineering Sciences, Volume 20, Issue 4, Pages 41-48

In this study a cylindrical liner was produced by horizontal centrifugal casting process. The liner was composed from aluminum alloy (A380) matrix reinforced with alumina particles (Al2O3) with grain size of (63−125)µ and volume percent of 10,15 and 20%. The die was rotated at different speeds and its temperature was remained constant at (350)ºC.
In this present study it was concluded that any increase in temperature difference between pouring and die temperature will reduce the surface defects. This study reveals that increasing the rotational speed refines the grain size but cause the alumina particles to be concentrated at the outer surface. Finally it was found that the addition of alumina particles increases both hardness and wear resistance of the alloy.

Experimental and Numerical Study of Heat Transfer Enhancement in a Shell and Tube Heat Exchanger using Helical Coiled Wire Inserts

Musa Mustafa Weis; Ehsan Fadhil Abbas; Ahmed Sami Ridha

Tikrit Journal of Engineering Sciences, Volume 25, Issue 2, Pages 74-79

An experimental work on heat transfer enhancement in a shell and tube heat exchanger by insertion of helical coiled wires into the tube bundle was conducted. Four different pitch sizes were used (4.8, 6.4, 8.0, 9.6) mm. The working fluid for both shell and tube sides of the exchanger was water. Flow arrangement used was parallel and laminar for both sides with a Reynolds number for the tube inside ranging (100-920). Variables were taken into account, including; convection heat transfer coefficient, number of heat transfer units, thermal effectiveness, and pressure drop. CFD analysis was done in order to validate the experimental results. The study results showed an increase in heat transfer coefficient on the tube side by 54% due to the use of 9.6 mm pitched inserts. Highest thermal effectiveness obtained was in the case of 9.6 mm pitch inserts. Pressure drop rose up to 260% due to inserts.

An Experimental Study to Show the Effect of Time of Opening and Closing the Solenoid Valve on Effectiveness of Finned Cross Flow Heat Exchanger

Tikrit Journal of Engineering Sciences, Volume 19, Issue 3, Pages 26-35

In this research an experimental study was carried out to show the effect of time of opening and closing the solenoid valve on the effectiveness of finned cross flow heat exchanger, which has changed the time of opening and closing the solenoid valve (2, 4, 6 sec.) with change the mass flow rate of water each time and the range values between (0.027-0.0816 kg/s) with constant of mass flow rate of air at (0.032 kg/s). The results obtained from experiment works that the decreasing in the time of opening and closing the solenoid valve from (6 sec.) to (2 sec.) leads to increase internal heat transfer coefficient (hi) the highest increase was by (18.37%) at mass flow rate of water
(0.027 kg/s) and increase the overall heat transfer coefficient (U) and the highest percentage of increase (7.36%) at mass flow rate of water (0.027 kg/s). The experimental results obtained show that the increasing both the number of units transmitted (NTU) and effectiveness of the finned heat exchanger when decrease the time of opening and closing the solenoid valve from (6 sec.) to (2 sec.) and the highest percentage of the increase occurring is (8.4%) and (1.74%) respectively at mass flow
rate of water (0.027 kg/s).

The Effect of the Capillary Tube Coil Number on the Refrigeration System Performance

Thamir K. Salim

Tikrit Journal of Engineering Sciences, Volume 19, Issue 2, Pages 18-29

The capillary tube performance for (R134a) is experimentally investigated. The experimental setup is a real vapor compression refrigeration system. All properties of the refrigeration system are measured for various mass flow rate from (13 – 23 kg/hr) and capillary tube coil number (0-4) with fixed length (150 cm) and capillary diameter (2.5mm).
The results showed that the theoretical compression power increases by (65.8 %) as the condenser temperature increases by (2.71%), also the theoretical compression power decreases by (10.3 %) as the capillary tube coil number increases.
The study shows also that the cooling capacity increases by (65.3%) as the evaporator temperature increases by (8.4 %), and the cooling capacity increases by (1.6%)as the capillary tube coil number increases in the range (0-4).
The coefficient of performance decreases by (43.4 %), as the mass flow rate increases by (76.9%), also the coefficient of performance increases by (13.51 %) as the capillary tube coil number increases in the range (0-4).
Through this study, it was found that the best coil number in refrigeration cycle at the lowest mass flow rate (13 Kg/hr) and at high mass flow rate (23 Kg/hr) is (coil number = 4), this will give the highest performance, cooling capacity and lowest theoretical compression power.
An experimental relationship has been adopted between the coefficients of performance (COP) against .
خلال هذه الدراسةِ وُجِد أن أفضل عددِ لفات في دورةِ التبريدِ عند اقل معدل تدفق (13 kg /hr) و أعلى معدل تدفق (23 Kg /hr) هو (عدد اللفات = 4)، والتي أعطت أعلى أداء وسعة تبريد واقل قدرة انضغاط نظرية.من هذه الدراسة استنبطت علاقة تجريبية بين معامل الأداء (COP) يقابل

Modeling and Simulation of Out of Step Blocking Relay forPower Swing Using Concentric Polygons Scheme

Tikrit Journal of Engineering Sciences, Volume 17, Issue 1, Pages 21-31

يتضمن هذا البحث دراسة تأثير تأرجح القدرة على أداء مرحلة حماية المسافة العاملة في خطوط الضغط العالي والفائق فضلاً عن دراسة استقرارية منظومة القدرة. وإذ إن مرحلة المسافة "التقليدية" غير قادرة على العمل بشكل طبيعي ضمن ظروف الاستقرارية العابرة، لذا سوف تعاني من قصور بالأداء مما يؤثر سلباً على إشارة الإفلات الصادرة منها. وللتغلب على هذه المشكلة تم تمثيل ونمذجة مرحلة الخروج عن التزامن والتي يمكن أن تُلحق مع مرحلة المسافة لأجل التحكم والإشراف على استجابة إشارة الإفلات ضمن هذه الظروف وتعتمد الخصائص التنظيمية لهذه المرحلة على طريقة مخطط متعدد الأضلاع المتمركزة كتقنية لكشف عن تأرجح القدرة وتحديد مدى خطورته. في هذا البحث تم تمثيل ونمذجة هاتين المرحلتين باستخدام برنامج تمثيل الدوائر الكهربائية والمحاكاة (MaltabSimulink) وتم اختبار عملهما على نظام افتراضي ثنائي التغذية. وقد أظهرت نتائج البحث مدى فعالية واعتمادية هذا الأسلوب للتحكم باستجابة إشارة الإفلات لمرحلة المسافة تحت ظروف الاستقرارية العابرة كما أوضحت إمكانية الكشف عن حالات الأعطال والتي يمكن أن تحدث أثناء فترة تأرجح القدرة.الكلمات الدالة: تأرجح القدرة، مرحلة المسافة، تقنية الحماية عند الخروج عن التزامن.

Study the Effect of Rotational Speed and Pouring Temperature on the Wear Resistance and Hardness of Alloy (A380) Reinforced with Different Volume Fraction of Alumina Particles

Tikrit Journal of Engineering Sciences, Volume 20, Issue 4, Pages 41-48

In this study a cylindrical liner was produced by horizontal centrifugal casting process. The liner was composed from aluminum alloy (A380) matrix reinforced with alumina particles (Al2O3) with grain size of (63−125)µ and volume percent of 10,15 and 20%. The die was rotated at different speeds and its temperature was remained constant at (350)ºC.
In this present study it was concluded that any increase in temperature difference between pouring and die temperature will reduce the surface defects. This study reveals that increasing the rotational speed refines the grain size but cause the alumina particles to be concentrated at the outer surface. Finally it was found that the addition of alumina particles increases both hardness and wear resistance of the alloy.

Use Of Crushed Bricks As Coarse Aggregate In Concrete

Fadia S. Kallak

Tikrit Journal of Engineering Sciences, Volume 16, Issue 3, Pages 64-69

The investigation reported in this paper is carried out to study the feasibility of using crushed bricks to substitute the coarse aggregate (gravel) in concrete. Two types of concrete mixing are prepared. The first one is a mixture of 1:2:4 without crushed bricks and is used as a reference mixture .The second one is made of different weight of crushed bricks (as a percentage from the weight of the coarse aggregate). A total of 30 numbers of concrete specimens are casted with and without crushed bricks and tested under compression and split tension as per relevant to British standard specifications.Test results indicated that using crushed bricks reduces the strength of concrete. Also, the percentage of water to cement ratio increases for constant slump when the percentage of crushed bricks increased. Key words: Recycled aggregate, Crushed bricks, Light weight concrete, Demolition waste.

Study the Effect Of Magnesium And Zinc Additions On Thermal Properties Of Pure Aluminum

Tikrit Journal of Engineering Sciences, Volume 19, Issue 4, Pages 74-84

This research, a practical study was achieved to demonstrate the effect of adding Magnesium and Zinc elements on the thermal properties of pure Aluminum. These properties are: the quality thermal capacity (Cv), the thermal conductivity coefficient (k), and the thermal diffusion coefficient ( ). Seven metal ingots were manufactured by changing the percentages of adding Magnesium and Zinc on the pure Aluminum, and these ratios were: (5%, 10%, 15%, 20%, 25%, 30%).
The obtained results showed that increasing the percentages of adding Magnesium and Zinc to the pure Aluminum causes a decrease in the ingot density by (10.7%), a decrease in the thermal conductivity coefficient by (8.1%), an increase in the quality thermal capacity by (4.8%), as well as a decrease in the thermal diffusion coefficient by (1.9%). As for Zinc, the density increases by (49.2%), as the density of Zinc (7.13)kg/m3 is higher than the density of Aluminum (2.7) kg/m3, and higher than the density of Magnesium (1.74) kg/m3, as well as decreasing the thermal specifications (Cv, k, ).
During this study, it was found that the best addition is (30% Mg) to the pure Aluminum, which gave the highest thermal properties (Cv, k, ). As for Zinc, its addition to pure Aluminum led to deterioration of the thermal properties during all ratios.

Control Techniques of Torque Ripple Minimization for Induction Motor

Tikrit Journal of Engineering Sciences, Volume 25, Issue 4, Pages 57-63

A Matlab-Simulink environment used to build a model of an Induction Motor (IM) to study and explore methods for minimizing the torque ripple. Various control strategies were reviewed and simulation studies were carried out for the following control methods: Direct Torque control, Direct Torque control with harmonic elimination, and Direct Torque control with Matrix convertor were the obtained results analyzed, evaluated, and compared to each other. The simulation results confirmed that Using Direct Torque Control with Harmonic elimination method was significantly minimized the torque ripple as the harmonics of the output voltage were canceled; discussions and conclusions were presented in this study..

THEORETICAL AND EXPERIMENTAL STUDY FOR LAMINAR FORCED CONVECTION HEAT TRANSFER THROUGH ACICULAR CROSS SECTION CHANNEL AND HEATED UNDER CONSTANT HEAT FLUX.

Tikrit Journal of Engineering Sciences, Volume 13, Issue 4, Pages 1-23

تم في هذا البحث دراسة عملية ونظرية للحمل ألقسري الطباقي خلال قناة دائرية المقطع ومثبتة بصورة أفقية ومملوءة بوسط مسامي مشبع ومستخدماً الهواء كمائع تشغيل وذات مسامية ونفاذية ثابتتان ومسخنة تحت ظرف ثبوت الفيض الحراري. شمل الجانب النظري حل عددي لمعادلة الزخم ذات البعد الواحد ومعادلة الطاقة ذات البعدين وباستخدام الفرو قات المحددة وبتقسيمات غير متساوية في الاتجاه الشاقولي ولقيم من انحدار الضغط تتراوح بين 103 إلى 106. أما معادلة الطاقة فاستعملت فيها الطريقة الضمنية أو الصريحة Implicit method والعملية الارتحالية Marching process لإيجاد قيم وتوزيع درجة الحرارة خلال مقاطع القناة . وتم مقارنة هذا النموذج بنموذج ذي مسامية متغيرة إذ لوحظ أن تغير المسامية وحدوث ظاهرة التخدد Channeling له تأثير واضح على زيادة معدل انتقال الحرارة و إن نسبة الزيادة في عدد نسلت تساوي 30%. و بينت الدراسة إن الزيادة في انحدار الضغط يؤدي إلى زيادة متباينة في معدل انتقال الحرارة في حين هذا التباين يختفي في منطقة تمام التشكيل الحراري. أجريت الاختبارات لثلاث قيم من أعداد بكليت هي (17 و 25 و40 ) مع تغير كمية الحرارة المجهزة عند كل عدد. أوضحت النتائج النظرية والعملية على السواء إن معدل انتقال الحرارة بدلالة عدد نسلت إنها تزداد بزيادة عدد بكليت .كما بينت الدراسة إن التوافق بين النتائج التجريبية والنظرية جيد وبخاصة لأعداد بكليت الواطئة حيث كانت نسبة التشتت20% ولوحظ شذوذ النتائج التجريبية عن النظرية لأعداد بكليت العالية وبنسبة تشتت مقدارها 40%.الكلمات الدالة حمل، قسري،قناة،وسط مسامي

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