Advanced Energy Technologies
Tamer Nabil; Mohamed Khairat Dawood; Tamer Mansour
Abstract
Since the renewable resources of energy have become extremely important, especially wind energy, scientists have begun to modify the design of the wind turbine components, mainly rotor blades. Aerodynamic design considered a major research field related to power production of a small horizontal wind ...
Read More
Since the renewable resources of energy have become extremely important, especially wind energy, scientists have begun to modify the design of the wind turbine components, mainly rotor blades. Aerodynamic design considered a major research field related to power production of a small horizontal wind turbine, especially in low wind speed locations. This study displays an approach to the selection of airfoil and blade design utilized in small horizontal wind turbines with low cut-in speed and with no gear box. Modeling of the flow depends on Computational Fluid Dynamics (CFD) and theory of Blade Element Momentum (BEM) methodologies. QBlade used (BEM) for wind turbine simulation and integrated with XFOIL for airfoils design to ensure the requested characteristics for wind turbine performance. MATLAB is used to calculate the final design parameters to be modeled in SOLIDWORK. The flow dynamics are explored with the aid of ANSYS Fluent 16. The application of specially designed blades grants start up at lower wind speeds. The designed blade is fabricated from polyurethane foam. Experimental study confirmed that, at low average wind velocity (4m/s), the fabricated small-scale horizontal wind turbines are considered to be a positive way to supply electricity with an average power rate of 9watt and efficiency of 8%.
Sajad Alah Rezazadeh; Iraj Mirzaie; Nader Pourmahmoud; Nima Ahmadi
Abstract
A full three-dimensional, single phase computational fluid dynamics model of a proton exchange membrane fuel cell (PEMFC) with both the gas distribution flow channels and the Membrane Electrode Assembly (MEA) has been developed. A single set of conservation equations which are valid for the flow channels, ...
Read More
A full three-dimensional, single phase computational fluid dynamics model of a proton exchange membrane fuel cell (PEMFC) with both the gas distribution flow channels and the Membrane Electrode Assembly (MEA) has been developed. A single set of conservation equations which are valid for the flow channels, gas-diffusion electrodes, catalyst layers, and the membrane region are developed and numerically solved using a finite volume based computational fluid dynamics technique. In this research some parameters such as oxygen consumption, water production, temperature distribution, ohmic losses, anode water activity, cathode over potential and the fuel cell performance for straight single cell were investigated in more details. The numerical simulations reveal that these important operating parameters are highly dependent to each other and the fuel cell efficiency is affected by the kind of species distribution. So for especial uses in desirable voltages, for preventing from the unwilling losses, these numerical results can be useful. Finally the numerical results of proposed CFD model have been compared with the published experimental data that represent good agreement.
