Vyšetřování aerodynamických charakteristik modelů větrných turbín se svislou osou rotace

This dissertation consists of an improvement done on 120 mm chord length asymmetric airfoil NACA 2412 to get better performance of wind turbine. It covers two main parts. First came the theoretical part where the 3D airfoil NACA 2412 was drawn in ANSYS Fluent to extract its aerodynamic characteristics with an inlet stream velocity of 40 m/s, then four other airfoils were generated by combining the lower surface of the NACA 2412 airfoil with the upper surface of other airfoils whether four-digit or five-digit NACA airfoils. These airfoils underwent the CFD domain to extract the coefficients of lift and drag under the same boundary conditions applied on the original NACA 2412 airfoil. The airfoils have shown higher lift and that was the time to jump into the second part of the study that consisted of 3D printing with all the necessary steps to achieve the perfect surface for testing in a real wind tunnel to extract the same aerodynamic characteristics in real life experiment. The analysis of the experimental results has shown a close similarity to the theoretical ones where these profiles recorded a noticeable quality when it comes to lift coefficients as well as the lift to drag ratio.Tato disertační práce se zabývá zlepšením asymetrického profilu křídla NACA 2412 o délce 120 mm pro dosažení lepšího výkonu větrné turbíny. Zahrnuje dvě hlavní části. Nejprve je uvedena teoretická část, kde byl 3D profil NACA 2412 vytvořen v ANSYS Fluent, aby byly získány jeho aerodynamické charakteristiky s rychlostí vstupního proudu 40 m/s, poté byly generovány čtyři další profily zkombinováním spodního povrchu profilu NACA 2412 s horním povrchem ostatních profilů, ať už čtyřmístných nebo pětimístných profilů NACA. Tyto profily byly podrobeny CFD pro extrakci koeficientů vztlaku a odporu za stejných okrajových podmínek, jaké byly použity na původním profilu NACA 2412. Profily vykazovaly vyšší vztlak, a to vedlo k druhé části studie, která sestávala z 3D tisku se všemi nezbytnými kroky k dosažení co nejdokonalejšího povrchu pro testování ve skutečném aerodynamickém tunelu, aby bylo možné získat stejné aerodynamické vlastnosti ve reálném experimentu. Analýza experimentálních výsledků ukázala blízkou podobnost s teoretickými výsledky, kde tyto profily zaznamenaly znatelnou kvalitu, pokud jde o koeficienty vztlaku i poměr vztlaku k odporu vzduchu.361 - Katedra energetikyvyhově

Local benefits factored in utility scale wind energy for a remote location

The publication presents the results of analysis of possible local benefits factored in utility scale wind energy for a remote location. Electricity is one of the most vital problems on the Earth, thus utility scale wind and solar energy devices are boosting economic development. Energy demand is constantly increasing, despite efforts to ensure the energy efficiency of devices. People are looking for more energy and electricity to consume. Although wind energy is still being researched and improved, modern generation of wind energy is becoming more and more effective and desirable. This publication presents an effective solution to this issue. It deals with the generation of green environment friendly electricity from wind turbine. The genuine idea is to provide energy for remote location using onshore wind turbines. An analysis of the demand for energy at a remote location and electricity consumption was made to provide preliminary calculations of the wind farm. The number of required turbines is determined taking into account all related factors. A specific wind turbine has been selected and proposed to provide the necessary location with the necessary amount of energy. The analysis carried out showed that the produced energy is environment friendly since there is no carbon dioxide emission

Green energy from a hybrid PV panels and wind turbine farm in Lebanon

The publication presents the results of analysis of green energy from a hybrid PV panels and wind turbine farm use in Lebanon. Electricity is one of the most critical problems in Lebanon. This publication presents an effective solution to this issue. It deals with the generation of green environment friendly electricity from photovoltaic (PV) panels and wind turbine. The genuine idea consists of placing these panels and turbines at the middle of the coastal highway since it is considered as a free land. The produced energy is fed directly to the off gird after being inverted using appropriate devices. The middle of the highway from Tyre to Sidon is considered to apply this research. The actual design consists of 15222 PV panels placed in pairs on a steel chassis among the entire 27300 m coastal distance, 2 meters wide and 7610 vertical axis wind turbines placed at a distance of 0.9 m away from each pair of PV panels. The total energy produced by the PV system is estimated to 7.4 GWh/y and 3.1 GWh/y at an average wind velocity of 4.04 m/s. In addition to its benefit from a free land, the produced energy is environment friendly since there is no carbon dioxide emission

Pollutants production, energy recovery and environmental impact of sewage sludge co-incineration with biomass pellets

This study describes the production of pollutants, energy recovery and environmental impact of the co-incineration of sewage sludge and biomass pellets. The main objective of this study is to describe the use of energy generated by co-incineration and to assess the environmental impact of emitted pollutants. Co-incineration takes place in five different blended. The combustion takes place in a fluidised bed reactor with an average combustion temperature of 915–939 ◦C. The combustion process is mapped by Fourier transform infrared spectroscopy, Continuous Mercury Monitoring Systems, thermocouples, pressures, and flows sensors. The results show that the concentrations of harmful substances, namely SO2 and NOX, reach values of 12.39–1730.33 mg•m–3 N for SO2 and 93.30–1156 mg•m–3 N for NOX. This means that the emission limits are exceeded 40 times for SO2 and 8 times for NOX in the worst case. Regarding heat recovery, the resulting value of potential energy recovery from the flue gas is 5.35–7.69 MJ•kg–1 , and as the sewage sludge content in the fuel increases, the heat recovery value decreases. The resulting values of pollutant concentrations are also analyzed using a life cycle assessment approach using the GaBi software. The results show that sewage sludge incineration has the greatest impact on climate change, terrestrial ecotoxicity, and human toxicity. Again, as the sewage sludge content in the fuel decreases, the hazardousness of the discharged flue gas decreases. This study presents a relatively promising option to use sewage sludge as a secondary fuel in large combustion sources under certain conditions.Web of Science32art. no. 10340