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Article
Effect of Current on Average Surface Roughness of Borosilicate Glass at EDM Machining and Comparison with Numerical Programs
تاثیر التیار المستخدم في عملیات القطع بالشرارة الكھربائیة على الخشونة السطحیة لزجاج البوروسیلیكات ومقارنتھا مع نتائج تحلیلیة

Authors: Wathik I. Mahdi --- Maan A. Tawfiq --- Shukry H. Aghdeab
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2009 Volume: 27 Issue: 6 Pages: 1026-1038
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Machining of electrically non-conducting materials like glass is still a major problem. The principle of electric arc was used to generate high electrical discharge (spark) at high currents to machine non-conducting materials at any hardness, which is a new approach.EDM system was build for machining of non-conducting cutting materials such as glass with new technology including the use of powder (graphite) mixed for dielectric solution (tap water) by supplied AC current values (200, 250, 300, 350 and 400A). Voltage of (70V) was used to cut 3mm thickness of borosilicate glass (BSG) to obtain the average surface roughness (Ra) of about (0.003-0.012μm) but the Ra before the machining was (0.005-0.006μm).Numerical program called "Simulent" has been used to investigate the process control for EDM by using GN, BPN, PN and VQN that could predict the Ra with accuracies of 94.236, 94.034, 96.628 and 92.875% respectively from training data sets.The differences on the Ra at different network models for 3mm thickness of BSG never exceed (8%) from testing data sets while the comparison of numerical results with experimental results of Ra among the measured values and prediction various network models, shows a differences between (1-8%).The best predication accuracy is by the use of PN than other network models.

قطع المواد غير الموصلة كهربائيا مثل الزجاج مازال مشكلة رئيسية 0مبدا القوس الكهربائي تم استخدامه لتوليد شرارات كهربائية ع الية عند تيارات عالية وبوجود مسحوق الكرافيت المضاف للماءالصافي واستخدام التيار المتناوب لقطع المواد غير الموصلة عند اية صلادة وهي طريقة جديدة تم بناء منظومة شرارة كهربائية لقطع مواد غير موصلة مثل الزجاج مع تقنية جديدة متضمنة(70V) استخدام مسحوق الكرافيت ممزوج مع الماء الصافي بتسليط تيار متناوب 0تم استخدام فولتية 3) للحصول على متوسط خشونة mm) 200-400 ) لقطع سمك A) وقيم تيار متناوب تتراوح بين ( 0.003-0.012 ) لكن الخشونة السطحية قبل التشغيل كانت - 0.005 μm) سطحية صغير جدا حوالي للسيطرة على عملية القطع بالشرارة (Simulent) 00.006 استخدمة برنامج رقمي يسمى μm) (Ra) متمثل بالتنبوء بمعدل الخشونة السطحية (GN, BPN, PN and VQN) الكهربائية باستخدام 1027 94.236 ) على التوالي من مجموعة بيانات , 94.034, 96.628 and وبدقة تتراوح (% 92.875 التدريب.3) لزجاج mm) الفرق لمعدل الخشونة السطحية عند نماذج لشبكة م ختلفة ولسمكالبوروسيليكات لايتجاوز عن (% 8) من مجموعة بيانات الاختبار 0مقارنة النتائج الرقمية مع النتائج التجريبية بين ان معدل الخشونة السطحية بين القيم المقاسة والتنبؤات لمختلف موديلات الشبكة وكان (1- الفرق بين .(% 8عن موديلات الشبكة الاخرى بسبب ان الشبكة المذكورة (PN) افضل دقة متوقعة باستخدام تستخدم مسار رياضي مفرد وموسع اقل من موديلات الشبكات الاخرى 0

Keywords

Surface Roughness --- EDM --- MRR --- REW.


Article
Study the Effect of Electrical Current on Average Surface Roughness of Borosilicate Glass at EDM Machining and Comparison Using Matlab Program

Authors: Shukry H. Aghdeab --- Ahmed A. Abulwahhab
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 6 Pages: 1157-1165
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Machining of electrically non-conducting materials like glass is still a majorproblem. The principle of electric arc was used to generate high electricaldischarge (spark) at high currents to machine non-conducting materials at anyhardness.EDM system was build for machining of non-conducting cutting materialssuch as glass including the use of powder (graphite) mixed for dielectric solution(tap water) by supplied DC current values (200, 250, 300, 350 and 400A). Voltageof (70V) was used to cut 3mm thickness of borosilicate glass (BSG) to obtain theaverage surface roughness (Ra) of about (0.003-0.012μm).Matlab program has been used to investigate the process control for EDM thatcould the Ra experimental and theoretical with accuracies of 94.236, 94.034,96.628 and 92.875% respectively.From the reading of the magnitude of the roughness it was found that differencesbetween the theoretical and experimental values for 3mm thickness of BSG wasnever exceed (8%).

Keywords

Surface Roughness --- EDM --- MRR --- REW


Article
The surface roughness of new fluoride releasing material after using three polishing protocols and storage in artificial saliva

Author: Maha A. Habeeb مها حبيب
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 1 Pages: 21-26
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; suchmethods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasiveaction. This study was done to assess the effect of three polishing systems on surface texture of new anteriorcomposites after storage in artificial saliva.Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for onemonth and then samples were divided into four groups according to surface treatment:Group A (control group):10 specimens received no surface polish and were subdivided into A1 (Giomer) and A2(Tetric®N-Ceram). Group B: 10 specimens received polishing with Air polishing devise (APD) and were subdivided intoB1 (Giomer) and B2 (Tetric®N-Ceram). Group C: 10 specimens received polishing with pumice and brush and weresubdivided into C1 (Giomer) and C2 (Tetric®N-Ceram). Group D: 10 specimens were polished with pumice andrubber cup and were subdivided into D1 (Giomer) and D2 (Tetric®N-Ceram). Testing was done by means ofprofilometer and statistically analyzed using analysis of variance test (ANOVA), LSD and student t-test. Also sampleswere photographed by special orthoplane camera using light polarizing microscope.Results: The results showed a highly statistical significant difference in surface roughness among Giomer subgroupsP<0.05. Also there was a highly significant difference P<0.05 when comparing Tetric subgroups according to type ofsurface treatment. Furthermore there was non-significant difference P>0.05 between groups according to the typeof restorative material used.Conclusion: The use of prophylactic surface treatment significantly increased Giomer and Tetric ceram surfaceroughness and the use of rotating brush has shown the roughest surface among all other types of prophylacticprotocols also Giomer had shown more surface roughness than Tetric ceram although the difference was notsignificant.


Article
Evaluation of the Surface Roughness for Three Different Types of Composite Resin Materials Using (Sof–Lex) Finishing and Polishing Systems: A Comparative Study

Author: Sabah A Ismail
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2013 Volume: 13 Issue: 22 Pages: 221-227
Publisher: Mosul University جامعة الموصل

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Abstract

Aim: To evaluate the surface roughness of three different types of light activated composite resin using (Sof-Lex) – polishing system, a profilometer study. Materials and Methods: A total of 30 resin com-posite disks were prepared from three different types of composite resin include 3 – groups. Group I: 10 specimens were prepared from light activated nano hybride (Tetric n – Ceram, Ivoclar – Vivadent – Liechtenstein). Group II: 10 specimens were prepared from light activated microhybride composite resin (Arabesk – Voco, Germany). Group III: 10 specimens were prepared from light activated poly-glas composite resin (Solitaire – 2, Heraeus, Kulzer, Germany). The resin blocks finished and polished using (Sof – Lex) polishing system. The specimens were analyzed for surface roughness using “Pro-filometer”. Results: Tetric n – Ceram composite resin showed the lowest roughness average (0.112 μm) followed by Arabesk composite (0.150 μm), Solitaire – 2 composite resin showed the highest roughness average (0.341 μm). Conclusions: Tetric n– Ceram (nano-hybride) was the best polished composite resin, showed the least roughness average.


Article
Effect of different polishing systems on the surface roughness of full-contour zirconia

Authors: Hussein Muhammed Wajih حسين محمد وجيه --- Adel F. Ibraheem عادل فرحان ابراهيم
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 4 Pages: 39-45
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Adjustment of any premature occlusal contact of any zirconia restoration requires its polishing orglazing in order to restore the smoothness of the restoration. The objective of this in vitro study was to evaluate theeffects of different polishing systems and glazing on the surface roughness of full-contour zirconia.Material and methods: Forty disks (diameter: 8 mm, thickness: 6.4 mm) were prepared from pre-sintered fullcontouredzirconia block; they were colored and sintered in a high-temperature furnace at 1500˚C for 8 hours. Thespecimens were then leveled and finished using grinding and polishing machine and adjusted using diamond disk.The specimens were then randomly divided into four groups (n=10), group I involves samples that were polished using(karat diamond polishing set, Vita zahnfabrik, Germany), group II involves samples that were polished with (zirconiapolishing kit, SMEdent, Shanghai, China), group III involves samples that were polished with (OptraFine® diamondpolishing system, Ivoclar Vivadent, Germany), while group IV involves samples that were glazed using glazingmedium (VITA Akzent Glaze AKZ 25, Vita zahnfabrik, Germany). Surface roughness values (Ra) (in μm) of all thespecimens were recorded at each stage of surface treatment of zirconia disks (leveling and finishing, adjustment ofthe samples and polishing / glazing) using surface roughness tester. Statistical analysis was carried out using one-wayANOVA and LSD tests.Results: The results showed that the glazing group recorded the lowest surface roughness mean value, followed by(OptraFine® polishing system), then (zirconia polishing kit) and finally (karat polishing set) which showed the highestmean of surface roughness. For all groups, there was a statistically very high significant difference of (Ra) valuebefore and after adjustment of the samples. Moreover, there was a statistically very high significant difference in (Ra)value when comparing the adjusted samples with the polished and glazed ones. Karat polishing set group showed astatistically highly significant difference with zirconia polishing kit group (P<0.01). Both, karat polishing set and zirconiapolishing kit groups showed a statistically very highly significant difference (P<0.001) with (OptraFine® polishingsystem) and glazing groups. On the other hand, no statistically significant difference was found between glazing and(OptraFine® polishing system) groups (P>0.05).Conclusions: Adjusting full-contour zirconia with diamond bur or disk resulted in a significant increase in (Ra) thatnecessitates its polishing or glazing to restore the surface smoothness. Furthermore, both glazing and OptraFine®polishing system provided the best surface smoothness, so glazing can be substituted with chairside polishing usingOptraFine® polishing system.

إن تعدیل أي إطباق مبكر سواء لتركیبات السیرامیك أو الزركون, یتطلب تلمیعھا أو إعادة تزجیجھا من أجل استعادة النعومة المطلوبة. إن الھدف من ھذه الدراسة المختبریة ھو لتقییمآثار نظم التلمیع المختلفة و التزجیج على خشونة سطح الزركون المعدل.تم تحضیر أربعین عینة من الزركون، تم تلوینھا و طبخھا في فرن ذو درجة حرارة عالیة ( 1500 درجة مئویة لمدة 8 ساعات).بعد ذلك تم تسویة اسطح العینات و صقلھا بواسطة جھازالصقل, و بعدھا تم تعدیل أسطح العینات بواسطة قرصماسي. تم تقسیم العینات بعدھا عشوائیا إلى أربع مجموعات كل مجموعة تحوي عشرة عینات.المجموعة الاولى تم تلمیع أسطحفي المجموعة الثانیة تم تلمیع أسطح العینات بواسطة (طقم التلمیع الخاص بالزركون), المجموعة الثالثة تم تلمیع أسطح عیناتھا ,(Karat العینات فیھا بواسطة (طقم التلمیع الماسيالمجموعة الرابعة تم تزجیج العینات فیھا بمادة تزجیج مناسبة. تم تسجیل قیم خشونة الأسطح (بالمیكرو متر) لجمیع العینات في المراحل ,(Optrafine® بواسطة (طقم التلمیع الماسيANOVA الثلاثة (التسویة والصقل، تعدیل سطح العینات ,تلمیع العینات/ تزجیجھا) بإستخدام جھاز قیاس خشونة السطح (البروفیلومیتر). وقد أجري التحلیل الإحصائي بتطبیق اختبار.LSD احادي الاتجاه و إختبارثم مجموعة (طقم التلمیع الخاصبالزركون), وأخیرا مجموعة (طقم ،(Optrafine® أظھرت مجموعة التزجیج أقل متوسط خشونة لأسطح العینات، تلیھا مجموعة (طقم التلمیع الماسيوالتي أظھرت أعلى متوسط خشونة. للمجموعات الأربع، كان ھناك فروق ذات دلالة إحصائیة عالیة جدا بین متوسط الخشونة قبل تعدیل العینات و متوسط (Karat التلمیع الماسيالخشونة بعد تعدیلھا. أیضا كان ھناك فروق ذات دلالة إحصائیة عالیة جدا في متوسط الخشونة بعد تعدیل العینات و متوسط الخشونة بعد تلمیع- تزجیج العینات. أظھرت مجموعة (طقمو (طقم التلمیع الخاص (Karat وأظھر كل من (طقم التلمیع الماسي .(P < فرق معنوي عالي إحصائیا مع مجموعة (طقم التلمیع الخاص بالزركون) ( 0.01 (Karat التلمیع الماسيبینما لم یظھر ھناك اي فرق معنوي ذات دلالة إحصائیة .(P < و (التزجیج) ( 0.001 (Optrafine® بالزركون) فرق ذات دلالة إحصائیة عالیة جدا مع مجموعتي (طقم التلمیع الماسي.(P= و (التزجیج) ( 0.774 (Optrafine® بین مجموعتي (طقم التلمیع الماسيو كإستنتاج, فإن فان نتائج البحث اشارت الى أن تعدیل سطح الزركون بواسطة قرص او مثقب ماسي أدى إلى زیادة كبیرة في متوسط الخشونة, مما یوجب ضرورة تلمیع سطحو (التزجیج) أفضل نعومة لسطح الزركون مع عدم وجود اي فرق احصائي بین (Optrafine® الزركون أو تزجیجھ لإستعادة نعومة السطح. قدم كل من (طقم التلمیع الماسيمعوضا عن الحاجة لتزجیج تركیب الزركون مع الحصول على (Optrafine® المجموعتین, و بالتالي , من الممكن ان یكون تلمیع سطح تركیب الزركون بواسطة (طقم التلمیع الماسينعومة سطح مشابھة.


Article
Investigation of Material Removal Rate and Surface Roughness for AISI 1015 Steel Rack Gear in Wire EDM Process

Authors: Mostafa Adel Abdullah --- Safaa Kadhim Ghazi --- Mustafa Mohamed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 12 Part (A) Engineering Pages: 2361-2370
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this work an investigation of the effects of various process parameters of Wire-EDM like Servo Feed (SF), pulse off-time (TOFF), pulse on-time (TON), as inputs impact on surface roughness (Ra) and metal removal rate (MRR) as outputs on steel (AISI 1015) utilizing nine specimens. With servo feed (500, 600 and 700)mm/min, pulse-of time (10,30,50) μsec, pulse on-time (20,25,30) μsec.The characteristics of cutting variables were determined by implementing Taguchi experimental design method. The importance level of the cutting variables for metal removal rate and surface roughnessis determined by implementing the analysis of variance (ANOVA).

Keywords

Taguchi --- ANOVA --- surface roughness --- MRR.


Article
Prediction of Surface Roughness and Material Removal Rate for 7024 AL-Alloy in EDM Process

Authors: Abbas Fadhil Ibrahim --- Mostafa Adel Abdullah --- Safaa Kadhim Ghazi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 15 Part (A) Engineering Pages: 2796-2804
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This paper studies prediction the values of MRR and surface roughness in Electrical discharge operations. It is a operation in which the material removal rate is machined with elevation spark in the midst work piece and electrode sunken through dielectric solution.Through use Taguchi found that the accuracy of the measured and prediction values that have been is 93% and 99% for each of the MRR and surface roughness respectively. The effect of different Electrical discharge machining factors are (Gap, pulse off time and pulse on time) to predict the (material removal rate) and (roughness). Note that connected pole that was used is copper. From (ANOVA) found that the large parameter effect on MRR is pulse-on 65% and pulse-off 25% while large parameter effect for surface roughness is pulse-on 96% . The least influential parameter for metal removal rate is the gap and the least influential parameter for surface roughness is pulse-off and Gap.

Keywords

EDM --- MRR --- Surface Roughness --- Prediction.


Article
EFFECT OF CURRENT AND ELECTRODE MATERIAL ON MATERIAL REMOVAL RATE (MRR) AND SURFACE ROUGHNESS (RA) IN EDM PROCESS
تأثير التيار الكهربائي ومادة العدة على معدل إزالة المادة والخشونة السطحية في عملية القطع بالتفريغ الكهربائي

Authors: Baqer Ayad Ahmed باقر أياد احمد --- Ahmed Basil Abdul wahhab احمد باسل عبد الوهاب
Journal: AL-TAQANI مجلة التقني ISSN: 1818653X Year: 2017 Volume: 30 Issue: 1 Pages: E105-E116
Publisher: Foundation of technical education هيئة التعليم التقني

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Abstract

Over the past decades, electrical discharge machining (spark machining) has been one of most widely used non-conventional manufacturing process for machining hard metals. It is considered as an electro-thermal machining process, in that the thermal energy resulted from the electric discharge (the spark) is utilized in removing materials from the workpiece. In this study the EDM is used to remove metal from the workpiece (Medium carbon steel alloy) using two types of electrodes (copper and brass) with different values of machining current (10, 20,30,and 40)A. The effects of current and electrode material on the material removal rate (MRR), tool wear rate (TWR), and surface roughness have been investigated. The results show that higher MRR, lower TWR and smother surface is obtained with the copper electrode compared with the brass tool. Higher MRR values with using copper electrode are (59.92, 65.42, 61.51, and 60.77) % at machining current (10, 20, 30, and 40) Ampere respectively.

عملية التشغيل بالتفريغ الكهربائي هياحد انواع القطع الغير تقليديوتعتمد على الطاقة الكهربائية- الحرارية في عملية التشغيل حيث يتم استخدام الطاقة الكهربائية لتوليد الشرارة الكهربائية وتتم ازالة المادة بواسطة الطاقة الحرارية المتولدة من هذه الشرارة. في هذه الدراسة تم استخدام عملية (EDM) لازالة المعدن من احد سبائك الفولاذ متوسط الكاربون باستخدام نوعين من الاقطاب (النحاس والبراص) وبقيم تيار (40,30,20,10) امبير.حيث تم دراسة تاثير كل من معدل ازالة المادة ومعدل تآكل القطب (العدة) والخشونة السطحية. وقد اظهرت النتائج ان اعلى معدل ازالة مادة واقل تاكل بالقطب وأنعم سطح تم الحصول علية باستخدام قطب النحاس بالمقارنة مع قطب البراص. اعلى قيم لمعدل ازالة المادة تم الحصول عليها باستخدام قطب النحاس هي (59.92, 65.42, 61.51, 60.77)% لقيم التيار (40,30,20,10) امبير على التوالي.

Keywords

EDM --- Surface Roughness --- MRR --- TWR


Article
Fatigue of Binary Blend Composite Materials

Author: Ekhlas Edan Kader
Journal: AL-NAHRAIN JOURNAL FOR ENGINEERING SCIENCES مجلة النهرين للعلوم الهندسية ISSN: 25219154 / eISSN 25219162 Year: 2018 Volume: 21 Issue: 2 Pages: 195-198
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Due to their very good mechanical properties of composite materials which led to a huge increase in its application in a lot of fields.Epoxy/ PS(polysulfide) composite materials behavior in fatigue was reported. different weight fraction of PS (2%,4% and6%) were studied .Surface roughness properties of the blended composites were found for all weight fraction of PS and their fatigue properties are studied .Fatigue test was carried with rotating bending method. The loading in the test was sinusoidal wave type. The loading wave ratio is R = -1 and the frequency of loading is applied to avoid temperature rise with a frequency equal to 5Hz. Fatigue strength ,fatigue life and fatigue limit of the tested composites from standard curves are calculated. The addition of PS resulted in an enhancement in the fatigue values and cause the surface roughness to decrease at a considerable rate, the blend hardness is reduced considering shore A test.


Article
The Effect of Surface Roughness on Thermohydrodynamic Performance in Misaligned Journal Bearings
تأثير خشونة السطح على الاداء الحراري للمساند المقعدية منحرفة المحاور

Authors: Mustafa Mohammed K. مصطفى محمد كاظم --- Basim Ajeel Abass باسم عجيل عباس
Journal: Al-Khwarizmi Engineering Journal مجلة الخوارزمي الهندسية ISSN: 18181171 23120789 Year: 2010 Volume: 6 Issue: 3 Pages: 61-76
Publisher: Baghdad University جامعة بغداد

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Abstract

In this work an approach has been developed to investigate the influence of surface roughness on thermohydrodynamic performance in aligned and misaligned journal bearings by considering an average flow model and deriving the shear flow factor for various roughness configurations, similar to the pressure flow factor. An average Reynolds equation for rough surfaces is defined in term of pressure and shear flow factors, which can be obtained by numerical flow simulation, though the use of measured or numerically generated rough surfaces. Reynolds, heat conduction and energy equations are solved simultaneously by using a suitable numerical technique (Finite Difference Method) to obtain the pressure and temperature distribution through the oil film thickness of the journal bearing. These equations are obtained for isotropic surfaces and for surfaces with directional patterns. The flow factors for these surfaces are expressed as empirical relations in term of normalized oil film thickness (h/&#963;) and surface characteristic (&#947;) defined as the ratio of x and z correlation lengths . The results of this approach showed increase in load carrying capacity and maximum pressure and decrease in maximum temperature in the case of stationary surface roughness (rough bearing and smooth journal) with transverse pattern. The results obtained through this work have been compared with that published by other works and found to be in a good agreement.

تم في هذا البحث اعتماد طريقة لدراسة تأثير خشونة السطح للمساند المقعدية منحرفة المحور على الاداء الحراري لتلك المساند ودلك بأخذ نموذج معدل الجريان بنظر الاعتبار واشتقاق معادلات الجريان القصية لوضعيات مختلفة لخشونة السطح وبشكل مماثل لمعاملات الجريان الضغطية. تم اعتماد معادلة رينولدز التي تتضمن معاملات الجريان القصية والضغطية والتي يمكن الحصول عليها عن طريق النمذجة العددية للجريان واستخدام السطوح ذات الخشونة المقاسة وتلك التي يمكن توليدها عدديا. تم حل المعادلات الحاكمة للموضوع والتي تتضمن معادلة رينولدز،معادلة الطاقة ،معادلة أنتقال الحرارة بالتوصيل،ومعادلة اللزوجة التي تأخذ بنظر الاعتبار اعتماد اللزوجة على درجات الحرارة، انيا باستخدام طريقة عددية مناسبة (طريقة الفروقات المحددة) وذلك للحصول على توزيعات الضغط ودرجات الحرارة خلال طبقة الزيت للمسند المقعدي.تم الحصول على المعادلات لسطوح ذات خشونة متماثلة في جميع الاتجاهات واخرى ذات مواصفات اتجاهية. تم ايجاد معاملات الجريان لهذه السطوح كعلاقات تجريبية بدلالة المعاملات (h/σ) و والتي تعرف بانها نسبة علاقة الطول بأتجاهي (x,y). أظهرت النتائج المستحصلة خلال هذا العمل زيادة في تحمل المسند للاحمال وزيادة قيمة الضغط الاعظم وانخفاض في قيمة درجة الحرارة الاقصى التي يبلغها الزيت في حالة السطوح ذات الخشونة الثابتة(stationary surface roughness) والتي تعني المساند التي يكون فيها السطح الداخلي للمسند خشنا وسطح المحور ناعما.

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