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Engineering Research Journal \
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  Engineering Research Journal \
  
 

[9000341.] رقم البحث : 9000341 -
FEEDFORWARD LOAD TORQUE COMPENSATOR COMBINED WITH PI SPEED CONTROLLER FOR HIGH DYNAMIC PERFORMANCE OF PMSM DRIVES /
  قطاع الدراسات الهندسية / الهندسه الكهربائيه
تخصص البحث : الهندسه الكهربائيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 9
  محمد شعبان زكي محمد سيد أحمد ( mszaky78@yahoo.com - 01280100810 )
  Load torque estimator, permanent magnet synchronous motor, speed controller, field oriented control.
  This paper presents a PI speed controller in conjunction with a feedforward load torque compensator in order to improve the dynamic performance of permanent magnet synchronous motor (PMSM) drives. The load torque estimator is used to provide a feedforward value in the speed controller in order to decouple the load torque from the speed control. This method can improve the PMSM dynamic performance against the disturbance torque without increasing the speed controller gain due to stability limitations. This can be achieved by dividing the electromagnetic torque in a feedforward value which should compensate the load torque, and a dynamic value which takes account of the speed variation. The load torque estimator compensates the speed control by setting a feedforward torque value through the q-axis current reference value. Therefore, the speed controller reaches immediately the speed reference value and a better response to load torque variations, which are detected and compensated leading to small speed variations, is obtained. The proposed controller with load torque compensator is examined through both simulation and experiments. The performance of IPMSM drive system with a conventional proportional-integral (PI) controller is presented in comparison with the proposed controller. The results show a significant improvement of the proposed controller, particularly during load torque variations and parameter variations.
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[9000342.] رقم البحث : 9000342 -
STABILITY IMPROVEMENT OF SUPERCONDUCTING GENERATORS USING ARTIFICIAL INTELLIGENCE-BASED STATIC VAR COMPENSATOR /
  قطاع الدراسات الهندسية / الهندسه الكهربائيه
تخصص البحث : الهندسه الكهربائيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 8
  رجائى عبد الفتاح صالح ( ragaeys@yahoo.com - 01002660520 )
  Superconducting generator, Transient stability, FACTS, Fuzzy logic control, Particle swarm optimization
  In this paper, superconducting generator (SCG) stability enhancement via coordinated design of a governor controller (GC) and a static VAR compensator (SVC)-based fuzzy logic stabilizer is investigated. The GC is a conventional lead stabilizer activated by the speed error signal, while the signal produced by the SVC-based stabilizer is based on the SCG speed deviation and acceleration, and on two fuzzy membership functions reflecting few simple control rules. An objective function is defined and the design problem of efficient GC and SVC-based fuzzy stabilizer is formulated as an optimization problem. Particle swarm optimization (PSO) technique is employed to search for optimal parameters of GC and SVC-based stabilizer. Simulation results show that the proposed PSO-tuned control scheme provides good damping to the SCG, and enhances its stability over a range of operating conditions.
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[9000343.] رقم البحث : 9000343 -
THEORETICAL INVESTIGATION INTO A PRESSURE WAVE SUPERCHARGER /
  قطاع الدراسات الهندسية / الهندسه الميكانيكيه
تخصص البحث : الهندسه الميكانيكيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 13
  أحمد حافظ العسكري ( dr_alaskary48@yahoo.com - 01223330490 )
  compression ignition engine, pressure wave supercharger, exhaust gas recirculation, supercharging
  Pressure wave supercharger (PWS) is widely used in different applications especially for charging the internal combustion engines. This device utilizes the pressure waves issued the exhaust manifold. These waves transmitted from the exhaust gas side to the air side causing compression effect required for charging process. The present work aims to build a mathematical model to address the behavior of PWS at a wide range of operating conditions. The proposed model employs the basic conservation equations of continuity, momentum and energy as well as the species transportation. The gas flow is treated as 1-D, time dependent, and non-reactive compressible fluid flow. These equations are solved together numerically by using two steps Lax-Wendroff scheme. This technique enables to simulate the pressure waves more accurately and precisely. A computer code has been built to simulate the effect of many parameters on PWS performance. These parameters are dimensions and cells size, number of cells, rotational speed of PWS, engine speed and the exhaust gas pressure. Synchronization between the engine speed and PWS speed requires mathematical coupling between the engine cycle and PWS. Therefore, real cycle simulation is performed taking into consideration combustion processes, valve timing, and the amount of residual gases. The results of the present model are compared with another data to validate the model. The comparison shows fair agreement. Using PWS with internal combustion engines leads to enhancing the engine power, volumetric efficiency and reducing NOx emissions.
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[9000344.] رقم البحث : 9000344 -
EXPERIMENTAL AND THEORETICAL STUDY TO ASSESS THE DYNAMIC IMPACT LOAD ON R.C BRIDGE /
  قطاع الدراسات الهندسية / الهندسه الميدانيه
تخصص البحث : الهندسه الميدانيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 6
  ياسر الحكيم
  Impact factor, Bridges, Surface roughness, Obstacle
  There are a lot of bridges in Egypt; most of them are used sto cross the River Nile or its branches and also to cross the streets to reduce the traffic jam. Due to some problems in the bridge itself or in the road after the bridge, it is required to reduce the velocity of vehicles on the bridge. In many cases obstacles are constructed on the bridge to reduce the velocity of the vehicles. These obstacles cause impact forces in the structural elements of the bridge. Also, due to the rough pavement or due to the bad maintenance of the expansion joints, the impact forces happen when the vehicles pass over the bridge. In this research the vibration responses of a typical R.C bridge, due to truck passing an obstacle on the bridge, were measured using accelerometer transducers connected to a data logger system. Signal processing operations were carried out on the recoded signals to enhance the data quality and to obtain the velocity and displacement from the acceleration response. Finite element model was developed for the bridge to evaluate the effect of vibration. The numerical model was subjected to the real recorded signals (displacement response). The stresses due to these vibrations were calculated and compared to the original stress of the bridge due to static loads. Then, an oscillator beam model was used to model the bridge, the obstacle, and the truck taking into consideration the interaction between them. The results of this model were compared to that obtained from the measured response to assure that the stresses due to the experiment are matched with that obtained from the oscillator beam model. Then a parametric study was performed to study the effect of the obstacle height, the wheel load, and the span of the bridge on the results. The impact factor obtained from the Egyptian Code for Loads was compared to that obtained from the numerical results to investigate the excessive stresses induced in the bridge due to the existence of an obstacle on the bridge. As a result of this study, recommendations and guidelines were suggested.
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[9000345.] رقم البحث : 9000345 -
MINIMIZING OF SCOUR DOWNSTREAM HYDRAULIC STRUCTURES /
  قطاع الدراسات الهندسية / General
تخصص البحث : General
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 9
  هيثم عبدالصمد
  Hydraulic structures, Hydraulic jump, Scour holes,semi- circular sill, Physical model.
  Local scour downstream control structures may cause sevier damage or complete failure to the control structures. Through this research, an experimental study was conducted using semi-circular sill. The suggested shape is easy to be used as an extra element to existing structures to minimize the scour downstream control structures. A hundred eighty nine experimental runs were carried out considering various heights and positions of sill with different flow conditions. A case of flat floor without sill was included as original case and to be compared with the cases using sill. The influence of using the semi-circular sill on the scour hole dimensions was evaluated. Obtained results were analyzed and graphically presented.
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[9000346.] رقم البحث : 9000346 -
BEHAVIOR AND DESIGN ASPECTS OF CONCRETE BEAMS REINFORCED WITH HYBRID STEEL-GFRP BARS /
  قطاع الدراسات الهندسية / الهندسه الميدانيه
تخصص البحث : الهندسه الميدانيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 9
  محمد عبد العزيز سعفان ( msafan2000@yahoo.com - 01004919623 )
  hybrid reinforcement; GFRP; durability; corrosion; deflection; cracking.
  This paper aims at investigating the structural behavior of simply supported concrete beams reinforced with hybrid reinforcement consisting of steel and glass fiber reinforced polymer (GFRP) bars. The proposed system utilizes the merits of ductility and stiffness provided by the steel reinforcement and the anticorrosion characteristics of GFRP. While, the steel bars were provided with an increased concrete cover to ensure extra protection against corrosion, the GFRP bars were laid near the bottom tension surface of test beams to control cracking. Different parameters influencing the structural behavior including the steel and the GFRP reinforcement ratios and the configuration of shear reinforcement were considered. The steel stirrups were used to confine only the elevated steel bars or to confine both the steel and the GFRP bars. A total of twelve beams were tested in flexure under four-point loading till failure. The load-deflection response, the cracking patterns and the failure modes were recorded. A design equation was proposed to predict the ultimate load of the hybrid test beams. The test results showed that the performance of the proposed system was successful in maintaining the flexure strength with adequate stiffness and improved the cracking characteristics compared to counterpart beams with conventional reinforcement.
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[9000347.] رقم البحث : 9000347 -
EXPERIMENTAL INVESTIGATION ON STEEL-CONCRETE BOND STRENGTH IN SELF-COMPACTING CONCRETE /
  قطاع الدراسات الهندسية / الهندسه الميدانيه
تخصص البحث : الهندسه الميدانيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 10
  منير محمد كمال ( prof_mounir@yahoo.com - 01065641276 )
  Self-compacting concrete; bond; push-out; dolomite powder; silica fume; fly ash.
  The objective of this research was to evaluate the potentials of self-compacting concrete (SCC) mixes to develop bond strength. The investigated mixes incorporated relatively high contents of dolomite powder replacing Portland cement. Either silica fume or fly ash was used along with the dolomite powder in some mixes. Seven mixes were proportioned and cast without vibration in long beams with 10 mm and 16 mm steel dowels fixed vertically along the flowing path. The beams were then broken into discrete test specimens. A push-put configuration was adopted for conducting the bond test. The variation of the ultimate bond strength along the flowing path for the different mixes was evaluated. The steel-concrete bond adequacy was evaluated based on normalized bond strength. The results showed that the bond strength was reduced due to Portland cement replacement with dolomite powder. The addition of either silica fume or fly ash positively hindered further degradation as the dolomite powder content increased. However, all SCC mixes containing up to 30% dolomite powder still yielded bond strengths that were adequate for design purpose. The test results demonstrated inconsistent normalized bond strength in the case of the larger diameter compared to the smaller one.
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[9000348.] رقم البحث : 9000348 -
IMPROVING THE EFFICIENCY OF RIVER ACTIVITIES /
  قطاع الدراسات الهندسية / الهندسه الميدانيه
تخصص البحث : الهندسه الميدانيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 6
  أمين محمد عادل أمين الغرباوي ( eng.aminelgharbawy@yahoo.com - 01003553301 )
  Power Plants, Navigation pass, River Islands, Numerical Model.
  This paper presents the effect of reforming the islands on enhancing the performance of a main river activity with minimum influence on the other activates. Nile River from Km 802 to Km 812 was selected for this study, as this part of the Nile River has two main activates isolated by two separate Islands. The main activity is a power generation by a thermal Power Plant, (El Kurimat Power Plant) which is suffering from sedimentation problems in front of its intake. The other activity is river navigation pass. 3D Mathematical model, Delft 3D, was used to simulate the study area and test the different scenarios of the study. Field measurements using advanced equipments were carried out to cover a distance of 10 km of the River Nile at study area. Intensive bathymetric survey around the existing structures within the surveyed area (groins, intakes or outfalls structures, Islands, etc) was implemented. The model constructed and calibrated using the measured data. Different flow condition of the Nile River; minimum, dominant and the maximum discharges were tested. The model showed that the connecting of the two Islands by a submerged weir with crest level lower than the minimum water level by 30 cm will reduce the sedimentation problem at the power plant intake by more than 40% with minimum significant changes on the navigation pass.
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[9000349.] رقم البحث : 9000349 -
GIS APPLICATION ON RISK HAZARDS ASSESSMENT, / THE NILE VALLEY, EGYPT
  قطاع الدراسات الهندسية / الهندسه الميدانيه
تخصص البحث : الهندسه الميدانيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 12
  أمين محمد عادل أمين الغرباوي ( eng.aminelgharbawy@yahoo.com - 01003553301 )
  Flood Model, GIS, DEM, Inundation Hazards, The Nile Valley.
  GIS has gained considerable importance in engineering applications particularly in the fields of hydrology and hydraulics. The present paper assessed the risk of the Aswan High Dam, AHD breaching, numerically. Flood model was chosen and was selected to be implemented. The outflow hydrograph due to fail of AHD are considered as the output of Abdelhaleem F. study (2011). Then, SOBEK 1D2D model was implemented in order to simulate the flood wave propagation and inundation area in the Nile Valley. Geographical Information Systems, GIS tools was used to manage the input and output results, and also was used to produce a precise Digital Elevation Model, DEM to the Nile Valley, Egypt, and implemented in order to determine the banks violation sites together with the inundation of surrounding areas. So the size of expected damage of national main structures, (Railways, roads, airports, etc) within the extension of the study area was identified using GIS spatial database. The final obtained raster maps were handled and analyzed mutually with up-to-date maps of GIS thus more applicable results. The time of flood wave propagations along the Nile was calculated in order to define the time of response for emergency measures to be operated. The results could put forward to a flood management plan and could suggest evacuation plans.
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[9000350.] رقم البحث : 9000350 -
تأثير البيئة المادية والغير مادية على التشكيل المعماري المكون للطابع مع ذكر مشروع حديقة الحوض المرصود كمثال /
  قطاع الدراسات الهندسية / الهندسه المعماريه
تخصص البحث : الهندسه المعماريه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 10
  إيمان محمد عيد عطية ( emanprof@hotmail.com - 01223271549 )
  البيئة المادية, تأثير البيئة الغير مادية.
  The adoption of the architectural formation language of a building with the environment represents a reflection of those environment facts on that building. where the environment is clear and honest in its content and doesn’t need to show or confirm what it has through a building or something else, so the adoption of the architectural formation language of a building with the environment doesn’t add enough to the environment as the environment itself adds to the formation of the building. We can divide the environment to its contents include physical and non-physical environment.
The physical environment is expressed by a group of elements that include locations, constructional plan, climate, available natural resources and economy. But the non-physical environment includes: the character, personality, aesthetic and expressional values and (social and cultural) levels. Here it comes the importance of the character among all the contents of the extensive environment and its effect on building designs, where it’s related with the place’s value and the time requirement for achieving determined formats that reflected negatively or positively on the constructional circumference.
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[9000351.] رقم البحث : 9000351 -
SIMPLIFIED DIGITAL CONTROLLER FOR VARIABLE FREQUENCY INVERTER FED THREE-PHASE INDUCTION MOTOR /
  قطاع الدراسات الهندسية / الهندسه الكهربائيه
تخصص البحث : الهندسه الكهربائيه
  Engineering Research Journal \ / Vol. 35, No. 2 - April 2012
  تاريخ تقديم البحث 10/11/2013
  تاريخ قبول البحث 10/11/2013
  عدد صفحات البحث 6
  جمال حافظ احمد
  Variable frequency inverter, digital controller, high frequency modulation and interfacing technique.
  This paper presents a simplified approach for a digital controller of variable frequency three-phase inverter supplied a three-phase induction motor. The performance characteristics with variable frequency supply have been studied and simulated by a computer program. The torque-speed characteristics of the motor varied with variation of the frequency. Torque-speed characteristics at different frequencies are presented. Interesting waveforms of the digital controller have been recorded. Frequency variation covers many industrial applications such as manufacturing rollman belly, water pumps, composers, chiller fans and some home application.
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