Coaxial (wire-cylinder) electrodes arrangements are widely used for electrostatic deposition of dust particles in flue gases, when a high voltage is applied to electrodes immersed in air and provide a strongly non-uniform electric field. The efficiency of electrostatic filters mainly depends on the value of the applied voltage and the distribution of the electric field. In this work, a two-dimensional computer simulation was constructed to study the effect of different applied voltages (20, 22, 25, 26, 28, 30 kV) on the inner electrode and their effect on the efficiency of the electrostatic precipitator. Finite Element Method (FEM) and COMSOL Multiphysics software were used to simulate the cross section of a wire cylinder. The results showed that the velocity of the liquid and the charge accumulation of the particles increased with the increase of the applied voltage and also the efficiency of the precipitator increased and reached 100% with an applied voltage of 30 kV.
The two dimensional steady, combined forced and natural convection in vertical channel is
investigated for laminar regime. To simulate the Trombe wall channel geometry properly, horizontal
inlet and exit segments have been added to the vertical channel. The vertical walls of the channel are
maintained at constant but different temperature while horizontal walls are insulated. A finite
difference method using up-wind differencing for the nonlinear convective terms, and central
differencing for the second order derivatives, is employed to solve the governing differential
equations for the mass, momentum, and energy balances. The solution is obtained for stream
function, vorticity and temperature as dependent variables
Heat transfer process and fluid flow in a solar chimney used for natural ventilation are investigated numerically in the present work. Solar chimney was tested by selecting different positions of absorber namely: at the back side, front side, and at the middle of the air gap. CFD analysis based on finite volume method is used to predict the thermal performance, and air flow in two dimensional solar chimney under unsteady state condition, to identify the effect of different parameters such as solar radiation. Results show that a solar chimney with absorber at the middle of the air gap gives better ventilation performance. A comparison between the numerical and previous experimental results shows fair agreement.
Reducing the drag force has become one of the most important concerns in the automotive industry. This study concentrated on reducing drag through use of some external modifications of passive flow control, such as vortex generators, rear under body diffuser slices and a rear wing spoiler. The study was performed at inlet velocity (V=10,20,30,40 m/s) which correspond to an incompressible car model length Reynolds numbers (Re=2.62×105, 5.23×105, 7.85×105 and 10.46×105), respectively and we studied their effect on the drag force. We also present a theoretical study finite volume method (FVM) of solvi
The research aims to evaluate Evaluation of the investments Iraqi fund for External development through the application of financial tools to a number of companies of the Iraqi Fund for External Development, and from the point of view to achieve the best returns from investment and the feasibility of the investments of the Iraqi Fund for External Development and the research community represents the Iraqi Fund for External Development and the amount of (28) A company, while the research sample is (4) companies (the Arab Petroleum Transportation Services Company, the Arab Iraqi Company for Livestock Development, the Bauhaus Company for prefabricated buildings and mineral installations, the Arab Fisheries Company) that were chosen
... Show MoreTax revenues are considered one of the important sources of public revenues for the state as one of the tributaries that finance the public treasury to implement development plans. Real estate taxes are one of the sources of obtaining tax revenues in the state, as it follows that there are a number of factors that affect these revenues, which requires the development of necessary solutions and recommendations to address the resulting effects. Accordingly, this research sheds light on tax revenues in general and real estate tax revenues in particular to indicate the extent of their contribution to the total tax proceeds, as the tax proceeds of the real estate tax were analyzed into the total tax proceeds for the years (2017-2021). A numbe
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The research aims to study the impact of the dimensions of fun in the workplace in achieving internal marketing And knowing the type of relationships That link the dimensions of fun in the workplace With each other, None of the researchers mentioned (to the researcher's knowledge) the link between fun in the workplace and internal marketing From this point of view the main objective is determined, which is to study the effect of fun in the workplace in internal marketing, The research was conducted at Al Salam Public Company for Communications and Information Technology The research community was represented by (308) employees of the aforementioned company , Where a random sample was selected tha
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