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The main aim of the present research work is focused on the influence of key parameters, such as; impinging angle, rotational speed, and concentration of sand in water on the behaviour and characterization of erosion process of stainless steel-type 316L. In the current study, special erosion testing machine has been designed and constructed locally conforming to standard specifications. It was observed that, at a given impinging angle, concentration, and rotational speed, the variation of volume loss with accumulative distance is generally linear and the erosion rate has been determined from the least square fit of the variation of erosion volume loss with accumulative distance. It was found that increasing the impinging angle increases initially the extent of erosion rate and reach maximum rate at angle of 60o. However, at higher impinging angle, there is a significant decrease in the erosion rate. The erosion rate increases considerably with increasing rotational speed from 550 r.p.m. to 1520 r.p.m. . It was also observed that increasing the concentration of sand particles to about 30 wt.%, increases the erosion rate. In all cases, the erosion rate is near a double after inserting the flow baffles compared to those cases without baffles, and has been attributed to increase of particles rotation and vortices in the flow. [ABSTRACT FROM AUTHOR]

This study has been established for Mosul area by using climatic data and information for estimation of evapotranspiration by using methods (Blany-Criddle), kharrufa, pan evaporation,Fao penman montieth) and comparison between them to reach to the best method this study showed that pan evaporation equation has a very good determination factor with Fao-penman montieth because this method depend on simple and easily obtained information in comparison with other methods so that this method is a more suitable use for Mosul area also this study showed that there is a correlation performance relationship between these method the value of determination factor for Blany - Criddle is (0.9922) and for pan evaporation is (0.9788) and Kharrofa equation (0.9536) in comparison with Fao-penman Montieth . [ABSTRACT FROM AUTHOR]

Considering the wide usage of induction motors in various industries and the limitation of applying speed sensors in some cases, sensorless drives have became very important and the challenge to increase the accuracy of estimation continues. This paper presents a novel method for sensorless speed control for IM's that not only improve the estimation and speed tracking in DTC but also eliminate the speed sensor in DTC. For this purpose all needed parameters for sensorless speed control such as stator flux, speed and load torque are estimated with the extended Kalman filter. In this method, noise due to system structure, voltage, and current sampling is eliminated in all the effective parameters. Simulation results show the increase in the precision of estimation and speed tracking. [ABSTRACT FROM AUTHOR]