Abstract

in this paper, (CFD) Computational Fluid Dynamics was used for a detailed burner design by the software Fluent (ANSYS). However, a number of numerical simulations were performed on a generic swirl burner and turbulence flow selection of a non-premixed which using syngas. However, non-premixed flames which characterized by relatively high temperatures, high NOx concentrations, and emission indices. The results showed that the presence of methane in syngas increases the peak flame temperature and the thermal NOx, significantly. Therefore, Investigation showed that effecting of H2, CO, and N2 contents in the fuel mixture level NOx emissions, thus the present compositions for pure methane are respectively influenced on syngas1 by (10% CH4, 45% H2, 45% CO) , syngas2 by (50% CH4, 10% H2, 40%N2) and syngas3 (60% CH4, 20% H2, 20%N2).

This paper aims to design, modeling and manufacturing a prototype composite winding machine used to produce corrugated composite tubes. Seven different types of tubes can be produced: Radial Corrugated Tube (RCT), Radial Corrugated Surrounded by Cylindrical Tube (RCSCT), Cylindrical Tube (CT), Tangential Corrugated Tube (TCT), Tangential Corrugated Surrounded by Cylindrical Tube (TCSCT), Combined Radial and Tangential Corrugated Tube (CRTCT), and Combined Radial and Tangential Corrugated Surrounded by Cylindrical Tube (CRTCSCT). All types can be produced with different size. Although it is designed mainly for composites, however, paper, and thin sheet of metallic materials can be used as raw material too. Different fiber forms can be used such as knitted, woven roving, continuous filament, or chopped mat of glass or carbon fiber. Corrugation profile can be changed to any required shape such as sinusoidal, triangular, square, rectangular, trapezoidal, or combination of any two or more profiles. The machine uses a special technique utilizing a mandrel that can be driven manually as well as automatically. A prototype of a designed machine have been manufactured, and tested. Two different samples of prospected products have been produced successfully.

The fuel burnup examination is vital to improve the operating of nuclear reactors safely and economically and it is essential information in the safety analysis report. This study focuses on determination of the percentage of the fuel burnup of the Tajoura Nuclear Research Centre (TNRC)'s reactor. All macroscopic cross sections as a function of fuel burnup were obtained by the WIMS-ANL code. The core calculations are generated by using REBUS-PC in order to evaluate the core effective multiplication factorkeff and fuel burnup at the end of the fuel cycle. The results of the fuel burnup show that that the maximum percentage of the burnup is 33 %. Moreover, the average fuel burnup percentage in the core is 31.5 % which leads to reload the core with fresh fuel or shuffling the fuel. In addition, There is an obvious agreement between the current results of all control rods worth and the experimental measurements.

The aim of the present work is to guarantee the safety of the Tajoura Nuclear Research Centre's reactor (TNRC) as a result of a hypothetical Loss of Coolant Accident (LOCA). Transient evaluation of the postulated LOCA in primary coolant system is executed using PARET/ANL Code. A large break (LB LOCA) is assumed and the location of the rupture is supposed to be in the main primary circuit pipe at the outlet of the storage pool i.e. 3.5 m above the reactor core's level. Therefore, the core is covered with water and natural convection mainly provides the cooling after the accident and stopping the primary circuit pumps. The simulations are performed at the operating power of the reactor equals to 9 MW and for 180 s after the postulated rupture. The results show that SCRAM occurs at 14 s after the transient and primary circuit pumps stop at 103 s. Therefore, the cooling of the core is achieved at the beginning by the forced convection then the reversal flow takes place and the natural convection roles the cooling. In addition, the results show that the reactor is safe since the clad surface temperature (8٦ °C) at the hottest channel is lower than the maximum permitted value this means the existence of sufficient water above the core to cool it by the natural convection.

ABSTRACT

In present day triple tube heat exchanger is the most common type heat exchanger widely use in ventilation & air conditioning systems, oil refinery and other large chemical process, because it suits high pressure application. The process in solving simulation consists of modelling and meshing the basic geometry of triple tube heat exchanger using CFD package ANSYS 14.0. The objective of the project is design of triple tube heat exchanger and study the flow and temperature field inside the triple tube using ANSYS software tools. The heat exchanger contains 3 tubes and 500 mm length triple tube diameter 75 mm. In simulation will show how the flow pattern in the triple tube of the heat exchanger with heat transfer effects the efficiency due to the new design of the geometry of triple tube, which results in a significant increase in heat transfer coefficient per unit pressure drop in the heat exchanger spaced reduced

The main goal of the current paper is focused to investigate the effect of isothermal heat treatment

temperature and time on microstructure and strength in a medium carbon vanadium titanium free micro

alloyed steel. Isothermal heat treatment was carried out in the temperature range 350 to 600 C° at

different holding times varying from 2s to 1200s followed by water quenching. Samples were

investigated using optical microscope (OM) and scanning electron microscopy (SEM) paired with

energy dispersive spectroscopy (EDS) and by compressive testing using a servo-hydraulic testing

machine. The results show that, the final microstructure of samples held at high temperatures (550 and

600°C) consists of polygonal intra-granularly nucleated ferrite idiomorphs, combined with grain

boundary ferrite and pearlite were produced and followed by retained austenite that transformed to

martensite upon quenching (incomplete transformation phenomenon). At intermediate temperatures

(450 and 500 °C) an interlocked acicular ferrite (AF) microstructure is produced, hence acicular ferrite

becomes prevalent in the microstructure at (450 °C). The microstructure after the heat treatment at

500°C consists coarse nonpolygonal ferrite grains separated by pearlite colonies. However, at low

temperatures (400 and 350°C), the final microstructure of the samples held at 350°C consists of

bainitic sheaves, where the sheave of parallel acicular ferrite plates, similar to bainitic sheaves but

intra-granularly nucleated were observed, which called in some references as sheaf type acicular ferrite

for samples isothermally treated at 400°C. Yield stress was determined by compression testing on samples

with final Microstructure, the results show that, the observed change in the microstructure is related by a

marked decrease of compressive yield strength, approximately from 1000 to 700 MPa.

For Arabic letters recognition, we achieve three of pattern recognition approaches namely gray level co-occurrence matrix (GLCM), local binary pattern recognition (LBP) and artificial neural network (ANN) and compare between them to result best performance. Two of these methods level co-occurrence matrix and local binary pattern recognition are used for feature extraction whereas in artificial neural network (ANN) we use the intensity values of pixels for input of the neural network. Two classifiers are used, the K-Nearest Neighbor classifier (KNN) for the LBP, GLCM and neural network classifier for (ANN) artificial neural network. Also, we evaluate the results by using leave one person out approach, fold classification and leave one out.