To evaluate the predictive capability of actuator disk (AD) models in simulating wakes different wind turbine designs, we compare results AD simulation with those surface (AS) for EOLOS, NREL and a variant (i.e., NREL-V) designs. Two types are considered, i.e., AD-R AD-NR corresponding to model without rotational effects, respectively. For models, force coefficients both obtained from AS simula...

We define a relative coincidence Nielsen number Nrel(f, g) for pairs of maps between manifolds, prove a Wecken type theorem for this invariant and give some formulae expressing Nrel(f, g) by the ordinary Nielsen numbers. Introduction. In [S2] pairs of spaces A ⊂ X and maps f : X → X such that f(A) ⊂ A were considered. A relative Nielsen number of such maps was defined, i.e. a lower bound of the...

Wind power has been widely considered in recent years as an available and a clean renewable energy source. The cost of wind energy production is currently the main issue, and increasing the size of wind turbines can reduce wind energy production costs. Hence, megawatt wind turbines are being rapidly developed in recent years. In this paper, an aerodynamic analysis of the NREL 5MW turbine is...

O. ANDRÉN , H. KIRCHMANN , T. KÄTTERER , J. MAGID , E. A. PAUL & D. C. COLEMAN TSBF-CIAT, PO Box 30677-00100, Nairobi, Kenya, Department of Soil Sciences, PO Box 7014, SLU, S-750 07 Uppsala, Sweden, The Royal Veterinary and Agricultural University, Bülowsvej 17, DK-1870 Frederiksberg C, Denmark, NREL, Colorado State University, Fort Collins, CO 80523-1499, USA, and Institute of Ecology, Ecology...

Objective: The aim of this research is to create a versatile approach produce cellulose from nipa fronds, which are sustainable resource. Methods: study focuses on determining the amount in effectiveness simplified physicochemical pretreatment, and purity isolated a-cellulose. biomass was pretreated using physical chemical methods analyzed through gravimetric analysis determine its composition,...

The Renewable Energy Materials Research Science and Engineering Center (REMRSEC) has made substantial progress in its research mission of identifying, launching and advancing innovative research directions in materials for renewable energy, and in its human resource mission of educating the next generation of renewable energy professionals, reaching out to students and the general community, an...

The installation of fixed offshore wind power systems at greater water depths requires a floating body the foundation system. However, this presents various issues. This study analyzes characteristics platform motion turbine system based on performance pitch controller. in generation system, change according to response speed blade controller since is installed unlike existing onshore Therefore...

In this study, two battery models for a high-power lithium ion (Li-Ion) cell were compared for their use in hybrid electric vehicle simulations in support of the U.S. Department of Energy’s Hybrid Electric Vehicle Program. Saft America developed the high-power Li-Ion cells as part of the U.S. Advanced Battery Consortium/U.S. Partnership for a New Generation of Vehicles programs. Based on test d...

In order to study the influence of wind shear on aerodynamic characteristics large turbines, taking 5MW turbine blade model published by NREL as research object, eddy simulation (LES) turbines was carried out using XFlow fluid software based Lattice-Boltzmann method (LBM). WALE turbulence used at 3, 11.2 and 25m/s speeds. The effect factors axial thrust torque is compared with data NREL. result...