eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
1
8
10.21608/erjm.2007.69888
69888
Original Article
AN OPTIMAL DESIGN OF SINGLE TUNED FILTER IN DISTRIBUTION SYSTEMS
S. allam
1
H. EI-hash
2
Department ofElectrica1 Engineering, Faculty of Engineering, Shebin-El-Kom
Egyph'an Electrical Transmission Co.. Canal Zone-High voltage sector
This paper proposes an optimal design of single hmed shunt passive filter for the Underground Ramsis Metro Substation (URMS) using Linear Programming technique as a conventional I technique and fuzzy linear programming (F'LP) technique as a modem technique. The optimal I filter parameters are obtained to overcome the harmonics generated in the voltage and current waveforms, due to the non-linear characteristics of the rectifiers, which distort the voltage and currents waveforms at the point of common coupling (PCC). The harmonic levels are analyzed at I I different loading conditions using the Fast Fourier Transform (FFT) on MATLAB optimization i program. The proposed optimal design of harmonic filter is based on minimizing the cost of the 1 filter parameters and its losses. Both techniques are applied on the system under study. From the 1 results, the THD levels of the line cunent and the bus voltage are reduced to be within the standard limits. A comparison between the optimal design filters are carried out using t
https://erjm.journals.ekb.eg/article_69888_f1eb921f2e46877071ad3086f7c49aca.pdf
Diesel generating unit
optimal PI control
Fuzzy logic control
augmented fuzzy control
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
9
15
10.21608/erjm.2007.69889
69889
Original Article
ROBUST CHATTER-FREE SLIDING MODE OBSERVER OF SENSORLESS INDUCTION MOTOR DRIVES
M. M. Mahmouh
1
M. Khater
2
Department ofElectrica1 Engineering, Faculty oflhgineering, Minoufya Universiy, Shebin El-Kom, Egyp
Department ofElectrica1 Engineering, Faculty oflhgineering, Minoufya Universiy, Shebin El-Kom, Egyp
Sliding mode observer with its salient features is considered one of the robust observers for flux and speed estimation of sensorless induction motor drives. However, the discontinuous switching function of the sliding mode observer causes a significant chattering which is considered a serious drawback. In this paper, a modified robust chatter-free sliding mode observer for sensorless induction motor drives is presented. The discontinuous switching hnction is replaced by a continuous one to eliminate chattering. The accuracy and robustness of the proposed sliding mode observer are examined at motor starting and load torque variations. A floating-point Digital Signal Processor (DSP) TMS320C31 control board with a hardwarelsoflware interface is used to implement the proposed sliding mode observer for speed estimation. Simulation and experimental results are presented and discussed
https://erjm.journals.ekb.eg/article_69889_f7313e6a60b393f6c2ba60d7b3043975.pdf
: Chattering
Sliding Mode Observer
Speed Sensorless
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
17
24
10.21608/erjm.2007.69891
69891
Original Article
LONG-TERM LOAD FO.RJXASTING AND ECONOMICAL OPERATION OF WIND FARMS FOR EGYPTIAN ELECTRICAL NETWORK
S. M. Allam
1
G. M. Atta
2
A. A. Abou El-Ela
3
A. A. El-Zefiawy
4
E!ectrical Engineering Dept.. Fac~rlp qfEng.. Shebin El-Kom, Egypt.
E!ectrical Engineering Dept.. Fac~rlp qfEng.. Shebin El-Kom, Egypt.
E!ectrical Engineering Dept.. Fac~rlp qfEng.. Shebin El-Kom, Egypt.
Many of traditional methods have been presented for long-term load forecasting of electrical power systems. But, the results of these methods are approximated. Therefore, artificial neural network (ANN) technique for long-term peak load forecasting is modified and discussed as a modern technique in long-term load forecasting. The modified technique is applied on the Egyptian electrical network dependent on its historical data to predict the electrical peak load demand forecasting up to year 2017. This technique is compared with extrapolation of trend curves as a traditional method. Installed power generation capacities of Egyptian electrical network up to year 2017 are estimated dependent on the peak load forecasting of this network. Also, a proposed methodology to assess the economical operation of WFs beside conventional power system (CPS) is introduced. This methodology includes a mathematical mode1 to develop the economical operation of wind farms on the whole power generation system capacity though the considered period.
https://erjm.journals.ekb.eg/article_69891_d41d8cd98f00b204e9800998ecf8427e.pdf
Long-term load forecasting
Artificial neural network- economical operation of wind farms
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
25
31
10.21608/erjm.2007.69892
69892
Original Article
PERFORMANCE ANALYSIS OF A BRUSHLESS DOUBLY-FED SINGLE-PHASE INDUCTION MACHINE
Mahmoud M. Khater
1
Deportment of Electrical Engineering, Factrlp oflngineering, Minouj-va Universiiy, Shebin El-Kom, Egyp
This paper introduces an alternative configuration for Brushless Doubly Fed Maclune (BDFM). The proposed machine is a single-frame induction machine provided with two electrically perpendicular sets of stator windings having the same number of poles with no direct transfonner coupling between them. The rotor is a conventional squirrel cage with no conditions imposed on its design and represents the only path for power transfer between the two sets of stator windings. The simulated results compare favorably with the experi~nental results. Towards this objective, it is hoped that the present work would be of some practical value in industrial applications.
https://erjm.journals.ekb.eg/article_69892_1538f1918f42a529cd7b2f36c358fb6b.pdf
Brushless doubly fed machine
Single-phase induction motor
Variable speed drive
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
33
41
10.21608/erjm.2007.69893
69893
Original Article
A MULTI-CHANNEL CONTROLLER FOR A SCG IN A MULTI-MACHINE POWER SYSTEM
G. A. MORSY
1
Deportment of Elecf~.icai Engineering, Fmrlty of Engineering, Mino~lfi)'(i Unii~el~ify, Sl~ehi~~-El-Ko?n, Eapt
This paper describes the development of a multi-channel control scheme to enhance the perfo~mance of a superconducting generatins (SCG) unit operated in a multi-machine power system. The proposed control scheme is designed and impleniented in the governor control loop of the SCG to overcome problems resulting fsom the low inherent damping nature of the SCG, which has structure different from those of the con\,entional synchronous machines. The design of the controller is based on developing an equivalent model of the SCG, which includes the effects of interactions with other generators. This simplifies the design procedures and produce control structure that use control signals measured from local generators only. The effectiveness of the controller is demonstrated by a detailed digital computer sirnulation of a multi-machine power system. The system consists of a 12-bus, 4-generators one of them is a 2000 MW SCG. The perfo~mance of the proposed controller is obtained and assessed in comparison with others, obtained using controllers designed by conventional techniques. It has been clearly denionstrated that the new controller improves the performance of the SCG, on which the controller is installed, as well as of all other generators in the network.
https://erjm.journals.ekb.eg/article_69893_495c650e4b7d51d53c3b7ca9727ef6d0.pdf
h/lultimachine power system. Superconducting generator
Multi-channel controlle~
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
43
51
10.21608/erjm.2007.69895
69895
Original Article
GAS-SOLID FLOW THROUGH EJECTOR
N. H. Mahmoud
1
Mofreh H. Hamed
2
A. A. Abdel-Hamied
3
A. A. Hussien
4
Mechanical Power Engineering Department, Faculty of Engineering, MinouJya University, Shebin El-kom, Egypt
Mechanical Power Engineering Department, Faculty of Engineering, MinouJya University, Shebin El-kom, Egypt
Mechanical Power Engineering Department, Faculty of Engineering, MinouJya University, Shebin El-kom, Egypt
Mechanical Power Engineering Department, Faculty of Engineering, MinouJya University, Shebin El-kom, Egypt
Single-phase (air-air) and two-phase (air-solid) flows throngh ejector are numerically and experimentally studied in this paper. The numerical model is performed using continuity equation for the gas phase and the solid phase separately, and the momentum equation for a homogenous mixture of gas-solid flow. The model takes into account the gas and solid friction with the wall and the drag force exerted on a particle by the gas. Three different geometries of the ejector are studied numerically and experimentally. The effects of the mixing chamber and tail pipeldiffuser, geometries on the ejector performance are studied. In addition, the effects of fluid motive pressure and the solid particle mass flow rate on the static pressure distribution are also studied. Comparisons are carried out between theoretical results and the present and published experimental data for the axial wall static pressure distribution. These comparisons show good agreements. The obtained results show that, geometry of convergent-constant-divergent of the mixing duct gives high vacuum pressure and preferable performance ofthe ejector.
https://erjm.journals.ekb.eg/article_69895_24efad2a1d2ab6ee04bd66e01e8ef3dd.pdf
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
53
66
10.21608/erjm.2007.69897
69897
Original Article
NUMERICAL AND EXPERIMENTAL INVESTIGATION OF COMPRESSIBLE FLOW EJECTORS
N. I. I. Hewedy
1
Mofreh H. Hamed
2
F. Sh. Abou-TaIeb
3
Tarek A. Ghonim
4
Mechanical Power Engineering Department Faculty of Engineering, Menoujya University, Shebin EL-Kom, Egypf
Mechanical Power Engineering Department Faculty of Engineering, Menoujya University, Shebin EL-Kom, Egypf
Mechanical Power Engineering Department Faculty of Engineering, Menoujya University, Shebin EL-Kom, Egypf
Mechanical Power Engineering Department Faculty of Engineering, Menoujya University, Shebin EL-Kom, Egyp
The present work deals with numerical and experimental investigation of supersonic air-air ejectors. The numerical investigation is based on flow equations governing turbulent, compressible, two-dimensional, steady, time averaged and boundary layer equations. These equations are continuity, momentum and energy. In addition, turbulent shear stress and heat transfer are calculated using eddy viscosity model. These equations are solved iteratively using finite difference method under the conditions of different flow regimes which can be divided into several distinctive regions where, the methods for estimating the mixing length are different for each flow region. The first region depicts the wall boundary layer, jet shear layer and secondary and primary potential flow. Tlle second one contains a single region of developing flow. The present results are concerned with the static pressure coefficient, temperature and velocity distributions along the mixing duct and diffuser. Also the overall efficiency of the ejectors for different flow conditions such as, motive air stagnation pressure and temperature, secondary air temperature and mass ratio is calculated. A simple ejector with convergent-divergent primary nozzle was fabricated and experimentally tested. The present theoretical and experimental results are compared with published data. This comparison shows a good agreement. The results obtained help to understand the flow behavior and physical phenomena occurring in the flow through ejectors.
https://erjm.journals.ekb.eg/article_69897_faed047a92c9cba7b63aae67b81cb755.pdf
supersonic flow
two-dimensional flow
turbulent and heat transfer
ejectors
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
67
76
10.21608/erjm.2007.69898
69898
Original Article
EFFECT OF SOLID CONCENTRATION ON A CENTRIFUGAL PUMP PERFORMANCE
S.M. Selim
1
M.A. El-kad
2
M.A. Hosien
3
,M.A. younes
4
I.R. Teaima
5
"' Department ofMechanica1 Engineering, Faculty of Engineering Minoufiya University, Shebin El-Kom, Egypt
"' Department ofMechanica1 Engineering, Faculty of Engineering Minoufiya University, Shebin El-Kom, Egypt
"' Department ofMechanica1 Engineering, Faculty of Engineering Minoufiya University, Shebin El-Kom, Egypt
Mechanical and Electrical Research Institute, Delta Barrage, Egypt
Mechanical and Electrical Research Institute, Delta Barrage, Egypt
Study on slnq pump performance has attracted much interest in many engineering fields. The influence of solids concentration on a pump operation has been investigated over the decades. When pumps are required to handle slurries, the pump head and efficiency are mainly affected by the solid size, solid concenmtion and solid density. The experiments were conducted with water, sand sluny, and clay sluny at operating pump speed. Measurements of power consumption, flow rate, total head developed by the pump and the density of the sluny were made in order to obtain the characteristic curves of the pump. The results have shown that the values of head generated by the pump and its efficiency are not only dependent on solid concentration but are also affected by particle size distribution of the solids and properties of the sluny.
https://erjm.journals.ekb.eg/article_69898_52dc826120dcd2c4f3865aabf5fec0f0.pdf
Slurry pump-Solids concentration-Head and efficiency ratios-Particle size distribution
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
77
88
10.21608/erjm.2007.69900
69900
Original Article
PREDICTION OF FRACTURE OF EGGSHELL USING OPERATIONAL MODAL ANALYSIS
Essin A.K Amer
1
. F. R Gomrr
2
Dep~rtment ofAgriculture Engineering Faculty ofAgriculhtraZ Minoufya Universi Shibin El-Kom, EGYPT
Department of Production Eng. & Mech Design, Faculty of Engineering Minoufya Universit Shibin El-Kom, EGYPT
Presence of crack in eggshell are suspect able due to higher speed in commercial egg grading machines, so non-destructive quality assessment of bioproducts using vibration analysis, the resonant frequency and the damping of the vibration are the main parameters for the nondestructive quality assessment. The focus of this research is to investigate the capability af the operational modal analysis as a nondest~ctive tool, to characterize and to quantify the fracture behavior of eggshell. This is achieved by studying the response of modal testing to the variation in strength as the main factor affecting fracture. This help in correlating modal parameters to fracture behavior. Two different methods are achievedl- traditional modal analysis using transfer fnnction between actuator and sensor and 2- operational modal analysis using transmittance function between pairs of sensors, input excitation was provided through a piezoelectric force transducer bonded to the center of the cup used for egg installation in order to extract the corresponding modal parameters and damping ratio. The test for strength was performed on eggs to correlated modal parameter to behavior of f~acture. This enables the evaluation of the ability of modal testing to predict fracture using an empirical formula. The damage index based on change in transmittance function is very sensitive to change in crack length. Structural information obtained about a biomaterial at diierent length scales is important in relating the structure to its funclional properties. This knowledge and the principles behind the formation of biomaterials could be used in the attempt of bioengineering new systems.
https://erjm.journals.ekb.eg/article_69900_178e1470822de85650540456850b1c16.pdf
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
89
97
10.21608/erjm.2007.69902
69902
Original Article
LONG TERM BIEHAVIOR OF GFRP REINFORCED CONCRETE BEAMS IN HARSH ENVIRONMENT
Mohamed A. Safaan
1
Civil Engineering Depavtment, Faculty of Engineering Menoufiia University, Egypt
The long-term and durability perfomlance of concrete beams reinforced with conventional steel and GFRP bar reinforcement in a harsh environment and under sustained load was investigated. Three simply supported beams (10Ox250x2700 mm) were reinforced using in-house manufactured GFW bars and stirrups, while three beams (100x200x2700 mm) were reinforced with high tensile deformed steel bars. One beam in each category was tested under fom point loading to determine the initial flexural capacity. The second beam was tested under a uniformly distributed sustained load in the laboratory atmosphere, while the third was fnrther subjected to wetfdry cycles and saIt solutions. The results of monitoring the tensile and compressive strains, mid-span deflection and cracking over a period of one year are presented. Signs of steel corrosion in the form of longitudinal cracks and increased tensile strains have been observed after 31 weeks in the prescribed harsh environment, while no damage was observcd in the similar GFRP reinforced beam.
https://erjm.journals.ekb.eg/article_69902_991a2cce4af3cb2f3db591051d249b0c.pdf
GFRP bars
RC beams
long-term
Durability
crack width
deflection
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
99
108
10.21608/erjm.2007.69903
69903
Original Article
OPTIMUM GEOMETRY AND INITIAL SHAPE FINDING OF CABLE STAYEID BRIDGES
, M Zidan
1
, M.N Fayed
2
, M.F Shuaib
3
, M.A Hilal
4
The optimum geometry design of cable stayed bridges could help in the material and the cost minimization of such structures. An optimum design algorithm has been proposed for the analysis and design of Cable Stayed Bridges (CSB), for their minimum weight. In this procedure, a computational method is presented to determine the initial shape of cable stayed bridges under the action of dead load of the girders and pretension in stay cables. The proposed optimum geometry design is achieved to satisfy both stress and displacement constraints, considering the member sizes and the geometrical design variables. A hybrid method is proposed by using the combination of a derived optimality criterion method and the suggested fully utilized design algorithm. Numerical investigations are performed to verify both the efficiency and the mathematical robustness of the proposed algorithm. The practical applicability of the proposed algorithm is made on the Suez Canal cable stayed bridge; the obtained results are analyzed and discussed
https://erjm.journals.ekb.eg/article_69903_9653e1fea98c66112e736a82ef3b1cd6.pdf
Optimum Geometry Design
Initial Shape. Cable Stayed Bridges
eng
Menoufia University, Faculty of Engineering
ERJ. Engineering Research Journal
1110-1180
2007-01-01
30
1
109
115
10.21608/erjm.2007.69906
69906
Original Article
DIAGNOSIS OF REACTOR CORE IMPACT USING WAVELET TECHNIQUE
Abdalla. M. Khattab
1
Kmbaby I. Mahmoud
2
Ornr M. abdelsalam
3
Hamdy M. Kelash
4
Magdi A. Kotb
5
Atomic Enxg) Autllority Egypt
Atomic Enxg) Autllority Egypt
Atomic Enxg) Autllority Egypt
Faculp of Electron~c Engineering , Minod~ya University
Faculp of Electron~c Engineering
This paper describes a new method for diagnosis of reactor cores using noise signal processing method. Detection and diagnosis of faults are based on the readings of signals coming from a set of detector tubes, which are surrounded by fuel assemblies in the reactor core. Vibrations of the detector tubes arise from the strong flow of coolant water in the reactor. If the vibration is large enough, the detector tube may impact on the nearby fuel assemblies, which in turn will execute a short, damped oscillation after each hit. This oscillation produces transient in neutron noise signal that is too small to be obselved. The traditional frequency analysis is not an effective tool for finding out transient in non-stationary signal and needs a reference or impact-free signal, that is often impossible to obtain in practical applications. In this work, we suggest a method to detect impact or transient in the signal, using one time the discrete wavelet transform @WT) and in the other an adaptive wavelet filter. The adaptive wavelet filter is found to be very effective in detection of detector vibration and impact problem early before its damage; therefore, the on-line diagnoses of the reactor will detect this error and if necessary alert the operator. The reactor with detector tube impact model is developed using Matlab-Simulink. The results show the effectiveness of the proposed method.
https://erjm.journals.ekb.eg/article_69906_fd7f2d141cb19734351f1c3a8dcf7835.pdf