| Mixture from the first generation bio-ethanol and gasoline, is one of the offered solution for human dependency to fossil fuels, which is one of the most highest energy supply on earth right now. In order to fulfill the high demand of bio-ethanol, research and development were needed to the bio-ethanol production line. One technique to develop high efficiency of bio-ethanol production is to reduce the stagnant/dead zones or cavern formation phenomena inside the stirred tank, by mechanical approach, which is manipulated the impeller geometry, with well-known numerical analysis program, ANSYS. The result from this research project is to variate the angle of attack from the blade and generate the new impeller design (dependent variables), which be able to eliminate the stagnant/dead zones or cavern formation phenomena, with the independent variables are power number (Po), pumping number (Nq), wall shear stress (?), mixing time (?n), and average effective viscosity (?). |