In this paper the sea breeze dynamics in Oran agglomeration atmosphere, in the north Algeria, is investigated and analyzed by a numerical simulation of Oran agglomeration atmosphere, using SUBMESO model during diurnal cycle of June 24, 2010, in order to predict the spatio-temporal starting of sea breeze, its intensity and relative direction through atmospheric flow variations analysis, and to evaluate the role of thermal circulations on sea breeze direction, intensity and ventilation and its effect on pollutant transport. The study of this area has not been investigated or analyzed in any framework, the numerical simulation was preceded by a topographic and surface data processing in order to generate the grid simulation, with a specific characteristics used by the SUBEMESO and SM2-U (Soil Model for Sub-Meso scales Urbanized) models. This simulation allowed us to know all sea breeze characteristics during the study period.

An efficient air ventilation requires knowledge of the complex interaction between the dynamic behavior and thermal parameters. For an isolated building the exact estimation of the interaction between the dynamics of cross-ventilation flow and a convective heat transfer, by overheating one of its internal walls, is an interest way to control the internal temperature’s distribution and the energy consumption of the ventilation system. The numerical simulation may provide an approximate solution to predict this kind of phenomenon. In this study, a numerical investigation of the thermal effect of a heated wall on a cross-ventilation for a generic isolated building with two parallel openings with a same dimension and at the same height is presented. The heat source is considered as solar radiation when it heats the exposed wall of the building. The wall temperature is assumed to be constant and homogeneous and it takes three values 25, 30 and 35°C. The highly three-dimensional flow is obtained by solving numerically the Reynolds averaged equations of mass, momentum and energy conservation for incompressible flow. The k-ω SST turbulent model is used to solve the turbulent quantities. The numerical results are validated by comparison of the horizontal component of velocity and the turbulent kinetic energy with the corresponding measurements. A detailed analysis of the interaction between the dynamic and thermal parameters is carried out and led to conclude that the distribution of the air temperature in the building is much influenced by the incoming fresh air jet. In its region the temperature difference between the air inside and outside the building is almost zero, however, below the jet region, characterized by air recirculation flow, the temperature takes its maximum value for the tree studies cases. Also, the thermal effects of air buoyancy may modify the dynamic behavior, especially at the building entrance, this modification is proportional to the wall temperature and it disappear after mid distance of the flow in the building.

The aeronautics studies and particularly the development of drones represent an important field, in which there is a very large number of research and studies.This article aims to present an experimental aerodynamic study of an autonomous surveillance unmanned aerial vehicle (UAV) that is capable of combining the advantages of both categories, namely the fixed-wing drones and the rotary-wing drones. To achieve this objective, a wind tunnel was used to study the flow around this drone in order to better understand the aerodynamic phenomena and to obtain some initial estimates of the lift, drag and moment coefficients, at three different Reynolds numbers of 4.02×104, 6.03×104 and 8.04×104, and for different angles of attack, from [−45°, +45°] with step of 1°.The experimental results obtained in this work show an casi-symetrical variation bertwen the negatif and positif incidence angles of the lift coeffecient, wiche indicate that the heliplane can fly in an inverted position, whatever the angle of incidence. Moreover, the minimum mean value of drag coeffecient according 1° incidence angle is 0.0478  then the drag due to geometry and pitching moment can never be canceled.

In this paper the sea breeze dynamics in Oran agglomeration atmosphere, in the north Algeria, is investigated and analyzed by a numerical simulation of Oran agglomeration atmosphere, using SUBMESO model during diurnal cycle of June 24, 2010, in order to predict the spatio-temporal starting of sea breeze, its intensity and relative direction through atmospheric flow variations analysis, and to evaluate the role of thermal circulations on sea breeze direction, intensity and ventilation and its effect on pollutant transport. The study of this area has not been investigated or analyzed in any framework, the numerical simulation was preceded by a topographic and surface data processing in order to generate the grid simulation, with a specific characteristics used by the SUBEMESO and SM2-U (Soil Model for Sub-Meso scales Urbanized) models. This simulation allowed us to know all sea breeze characteristics during the study period.

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