@article{elfering_metoyer_chatterjee_mazzoleni_bryant_granlund_2023, title={Blade element momentum theory for a skewed coaxial turbine}, volume={269}, ISSN={["1873-5258"]}, url={https://doi.org/10.1016/j.oceaneng.2022.113555}, DOI={10.1016/j.oceaneng.2022.113555}, journal={OCEAN ENGINEERING}, author={Elfering, Kelsey and Metoyer, Rodney and Chatterjee, Punnag and Mazzoleni, Andre and Bryant, Matthew and Granlund, Kenneth}, year={2023}, month={Feb} }
@article{metoyer_bryant_granlundt_mazzoleni_2022, title={Increased Energy Conversion with a Horizontal Axis Turbine in Translation}, ISBN={["978-1-6654-6809-1"]}, ISSN={["0197-7385"]}, DOI={10.1109/OCEANS47191.2022.9977131}, abstractNote={When fixed to the ground by tower or stanchion, horizontal axis turbines convert hydrokinetic power into electric power by passively exploiting the difference in velocity between the ground and a flowing fluid. This method of converting the available hydrokinetic power is relatively simple, but the maximum amount of power that may be converted to another form by the turbine has a theoretical upper limit, called the Betz limit, which is about 59.25% of the hydrokinetic power in a stream tube of the freestream flow with a cross sectional area equal to the area of the turbine rotor plane. The work presented demonstrates that eschewing the stanchion and making the turbine to translate through the fluid enables conversion of more hydrokinetic power and, when operated in a cyclical mode, more energy over a cycle. It is demonstrated with momentum theory that the maximum energy that may be converted over a cycle is 1.5 times the Betz limit for an equivalent ground-fixed stationary turbine in the same low. Following the theoretical analysis, the concept is proven by simulation for a non-ideal turbine using an engineering design tool developed by the United States National Renewable Energy Laboratory. The results show that a realistic, non-ideal translating turbine can convert over twice as much power as an equivalent stationary turbine. Additionally, a notional tidal current application is presented where the bidirectionality of flow is exploited to achieve energy conversion of more than twice the theoretical limit of an ideal stationary turbine.}, journal={2022 OCEANS HAMPTON ROADS}, author={Metoyer, Rodney and Bryant, Matthew and Granlundt, Kenneth and Mazzoleni, Andre}, year={2022} }
@article{metoyer_chatterjee_elfering_bryant_granlund_mazzoleni_2021, title={Modeling, simulation, and equilibrium analysis of tethered coaxial dual-rotor ocean current turbines}, volume={243}, ISSN={["1879-2227"]}, DOI={10.1016/j.enconman.2021.113929}, abstractNote={Tethered multirotor axial flow turbines have been proposed to overcome the many challenges associated with extracting ocean current energy where deep waters render seabed mounting strategies infeasible. However, flexible systems are inherently more susceptible to perturbation than fixed systems. The effects of flow misalignment on the hydrokinetic energy conversion of multirotor coaxial turbines have been investigated recently; however, the spatial dynamics and equilibrium behaviors of tethered coaxial turbines have not been well characterized, limiting the ability of designers to explicitly tailor the device behavior. In this work, a computational model of a dual-rotor coaxial turbine is presented, and the model is employed to explore the equilibrium behavior of the turbine with variations in parameters. A complete characterization of the hydrostatic state of the system and a comparative study of representative tethered turbine simulation cases is also presented. Two important findings are presented. First, that a positively buoyant dual-rotor turbine that is anchored to a surface-dwelling platform can operate where the turbine is located at some desired depth below the surface. Second, that more than one turbine system may be anchored to a single point while maintaining the desired orientation and position of each turbine to avoid collision and maximize energy production. The results and methods presented in this paper may be used to inform application-specific coaxial turbine design and to develop additional targeted empirical and simulation studies.}, journal={ENERGY CONVERSION AND MANAGEMENT}, author={Metoyer, Rodney and Chatterjee, Punnag and Elfering, Kelsey and Bryant, Matthew and Granlund, Kenneth and Mazzoleni, Andre}, year={2021}, month={Sep} }
@article{khatri_chatterjee_metoyer_mazzoleni_bryant_granlund_2019, title={Dual-Actuator Disc Theory for Turbines in Yaw}, volume={57}, ISSN={["1533-385X"]}, DOI={10.2514/1.J057740}, number={5}, journal={AIAA JOURNAL}, author={Khatri, Dheepak N. and Chatterjee, Punnag and Metoyer, Rodney and Mazzoleni, Andre P. and Bryant, Matthew and Granlund, Kenneth O.}, year={2019}, month={May}, pages={2204–2208} }