The thermal and electrical performance of different designs of air based hybrid photovoltaic/thermal collectors is investigated experimentally and theoretically. The circulating air is used to cool PV panels and to collect the absorbed energy to improve their performance. Four different collectors have been designed, manufactured and instrumented namely; double PV panels without cooling (model I), single duct double pass collector (model II), double duct single pass (model III), and single duct single pass (model IV) . Each collector consists of: channel duct, glass cover, axial fan to circulate air and two PV panel in parallel connection. The temperature of the upper and lower surfaces of PV panels, air temperature, air flow rate, air pressure drop, wind speed, solar radiation and ambient temperature were measured. The power produced by solar cells is measured also. A theoretical model has been developed for the collector model IV based on energy balance principle. The prediction of the thermal and hydraulic performance was obtained for the fourth model of PV/T collector by developing a Matlab computer program to solve the numerical model. The experimental results show that the combined efficiency of model III is higher than that of models II and IV. The pressure drop of model III is less than that of models I and IV, by (43.67% and 49%). The average percentage error between the theoretical and experimental results was 9.67%.
The mind map represents a system to solve problems including design problems, because it depends on employing the complex and purposeful mental activity, which starts from a desire based on the search and investigation in order to reach integrated results of scientific thinking, utilizing the objective view of the scientific and practical aspects from various angles. This visual system can develop thinking and shorten the retrieval time of the previous information in order to employ it in the solution finding system, that it evokes past experiences and relates them to current situations, then enables the user to choose a suitable solution for the problems. This visual, educational and circulatory means, at the same time, has speci
... Show MoreIn this research was conducted to provide a product to analyze the performance sensor fiber optic used to measure and feel the intensity of the electric field results showed obtained that use sensor long gives reactive high electric field strength and a high value for allergic sensor, but that is at the expense of reducing the intensity of the electric field that is detected
Crime is considered as an unlawful activity of all kinds and it is punished by law. Crimes have an impact on a society's quality of life and economic development. With a large rise in crime globally, there is a necessity to analyze crime data to bring down the rate of crime. This encourages the police and people to occupy the required measures and more effectively restricting the crimes. The purpose of this research is to develop predictive models that can aid in crime pattern analysis and thus support the Boston department's crime prevention efforts. The geographical location factor has been adopted in our model, and this is due to its being an influential factor in several situations, whether it is traveling to a specific area or livin
... Show MoreFor cleaner air and unpolluted continue assessment study air pollution the city of
Baghdad by measuring the concentrations of air pollutants, which included TSP, Pb, where
the adoption of three stations (Andalus Square, Jadiriya, Allawi) are distributed in the city of
Baghdad in order to compare the concentrations of these pollutants with previous studies.
Study pointed out that the city's air contaminant, especially in minutes outstanding after
deducting the amount of atmospheric dust thick mechanism city this year where the highest
concentration of minutes outstanding (9895) micrograms / m 3 at the station Alawi and lower
concentration of 157 micrograms / m 3 at the station Alawi and this was higher than the
det
Energy use is second to staffing in building operating costs. Sustainable technology in the energy sector is based on utilizing renewable sources of energy such as solar, wind, glazing systems, insulation. Other areas of focus include heating, ventilation and air conditioning; novel materials and construction methods; improved sensors and monitoring systems; and advanced simulation tools that can help building designers make more energy efficient choices. The objective of this research is studying the effect of insulations on energy consumption of buildings in Iraq and identifying the amount of energy savings from application th
... Show MoreTo reduce the effects of discharging heated water disposed into a river flow by a single thermal source, two parameters were changed to get the minimum effect using optimization. The first parameter is to distribute the total flow of the heated water between two disposal points (double source) instead of one and the second is to change the distance between these two points. In order to achieve the solution, a two dimensional numerical model was developed to simulate and predict the changes in temperature distribution in the river due to disposal of the heated water using these two points of disposal.
MATLAB-7 software was used to build a program that could solve the governing partial equations of thermal pollution in rivers by using t
I came back and made my jewelery from the first research or studies known to man, and the oldest era and confirmed the problem of searching for the links of sweets and admiration of the magnificence of the effectiveness of the search for the importance of preserving the heritage of the Iraqi civilization in its original creative aspects. Metal in Iraq, Head Costume, Neck Costume, Party Costume (Hands and Legs). The main results of the research were;
1-Contemporary folk jewelry in Iraq was characterized by design units for use.
Dependence in the feed industry in the form of laboratory mold.