Prediction of two bladed horizontal axis wind turbine acoustics

Wind power industry has been a growing market and maturing technology for several decades. Increasing wind power generation necessitates closer installation of wind turbines to people and their residences. For that reason, wind turbine noise becomes a serious and controversial phenomenon and it is anticipated to become more stringent issue while wind power generation is increased recently. The aim of this study was to propose a methodology to predict the wind turbine blade noise by using two dimensional blade section flows and noise analysis/simulation and combining the noise sources to evaluate the total blade noise with reasonable accuracy. Within the scope of this work, the purpose was to perform a two dimensional flow and noise simulation for the two bladed NREL Phase VI wind turbine with the aid of a commercially available Computational Fluid Dynamics (CFD) software ANSYS-FLUENT by using User Defined Functions after applying some corrections under certain assumptions. Analysis results were compared with the 12% scaled model of NREL Phase VI wind turbine acoustic noise measurements conducted in In Korea Aerospace Research Institute (KARI) at the low speed wind tunnel. Blade noise of the measurements were compared with the analysis results at different wind speeds of 5.4 m/s, 7.4 m/s, 12.3 m/s, and 13.3 m/s. For the tip region and inboard area of the blade, reasonable agreement was achieved at certain wind speeds. Additionally, the summation of the contribution from the each blade section was used to predict the total noise emission

Physiconomics for the Identification of Relativistic Satisfaction

Abstract Recent developments in identifying economic and social phenomena within the theory and laws of physics do not provide a sufficient basis of information for economists. In this article, an interdisciplinary analysis in microeconomics, is proposed to overcome this limit by establishing a new economic theory in the way of better analyzing economic problems from the methodological perspectives of physics. This new theoretical approach is tested on a model using individual time use values that identifies how life satisfaction may be defined through economic utility so as to better investigate the income-happiness paradox as pointed out by Easterlin. The theoretical analysis point out that an increase in happiness would depend on the ability to replace subsidiaries with conspicuous consumption so long as they have common characteristics that satisfy the same needs. This consumption pattern implies that consumers would draw more satisfaction from less usage of conspicuous goods than from higher usage of subsidiaries, under given budget and time constraints

The molecular mechanisms of mitosis and meiosis: Review [Mitoz ve mayozun moleküler temelleri]

In order to understand the function of the cell, which is the basic unit of human organism, the fundamentals of cell replication should be elucidated. Cell cycle checkpoints work in balance during the cell division process. The most important step in cell replication is to copy its own genetic material. During replication, mitosis lasts only 1 hour whereas 95% of the cell cycle process comprises the interphase. G1, S, G2 and M phases of the cell cycle are strictly controlled by the cell itself. Cell cycle checkpoints are sensitive to and control the errors that occur during the replication process, misegregation of the chromosomes, errors in DNA replication and any other errors that can occur during replication, thus maintaining the cell cycle. The molecules that have a role in the cell cycle and mitosis such as MPF (maturation promoting factor), cyclines and cell cycle inhibitors have very important functions, and proper maintenance of the cell cycle depends on the interaction between them. On the other hand, interaction between the different growth factors and cyclins during the switch to silent phase, the cell cycle inhibitors (p21 and TGF-ß) during the termination of the cell cycle, and the tumor suppressor genes (p53 and Rb) have major roles in the maintenance of the cell cycle. DNA packaging, chromosome condensation, formation of mitotic spindle and cytokinesis are under control during mitosis. In this review, the steps in mitosis and meiosis, the control points and the functions of major modulator molecules during the cell cycle are broadly reviewed with referral to recent findings. Copyright © 2007 by Türkiye Klinikleri

Evaluation of the SMN and NAIP genes in a family: homozygous deletion of the SMN2 gene in the fetus and outcome of the pregnancy.

PubMed ID: 19397406[No abstract available