by George Z. Voyiadjis  and Peter I. Kattan

Received: 27 October 2020;  Published: 10 May 2021;  doi: 10.21926/jept.2102021

A robust mathematical method for the characterization of damage in carbon nanotubes is presented the presentation here is limited to elasticity. In this regard, the second and third order elastic stiffnesses are employed. All this is based on damage mechanics. The hypotheses of elastic strain equivalence and elastic energy equivalence are utilized. A new damage variable is proposed that is defined in terms of the surface area. This is in contrast to the classical damage variable which is defined in terms of the cro [...]

by Antonio Vázquez-López  , Marina García-Carrión  , Erlend Hall  , Anisa Yaseen  , Ilknur Kalafat  , María Taeño  , Junjie Zhu  , Xinyu Zhang  , Elif Arici  , Omer Suat Taskin  , David Maestre  , Emilio Nogales  , Pedro Hidalgo  , Julio Ramírez-Castellanos  , Bianchi Méndez  , Neslihan Yuca  , Smagul Karazhanov  , Erik S. Marstein  and Ana Cremades

Received: 09 November 2020;  Published: 08 May 2021;  doi: 10.21926/jept.2102020

Hybrid composites based on inorganic nanomaterials embedded into a polymer matrix have were synthesized and characterized. Oxide semiconductor nanoparticles (SnO, SnO2, TiO2, Ga2O3, and NiO) and Si nanoparticles were employed as inorganic counterparts in the hybrid composite, while a conductive polymer (PEDOT:PSS) with diverse additives was used as the organic matrix. The composites were spin-coated on Si or glass substrates. The potential use of these materials in photovoltaic devices to improve Si surface passiva [...]

by Nobuyuki Imanishi  , Tao Zhang  , Tao Zhang  , Daishuke Mori  , Sou Taminato  , Yashuo Takeda  and osamu yamamoto

Received: 21 February 2021;  Published: 08 May 2021;  doi: 10.21926/jept.2102019

Because lithium metal exhibits high specific capacity and low potential, it is the best candidate for fabricating anodes for batteries. Rechargeable batteries fabricated using lithium anode exhibit high capacity and high potential cathode; these can be potentially used to fabricate high energy density batteries (>500 Wh kg–1) that can be used for the development of next-generation electric vehicles. However, the formation and growth of lithium dendrites and the low coulombic efficiency recorded during lithium plati [...]

by Yi-Chun Hsu  , Min-Ze Lu  and Chang-Ming Liaw

Received: 18 December 2020;  Published: 28 April 2021;  doi: 10.21926/jept.2102018

This paper proposes a Wind Turbine Emulator (WTE) using an Indirect Field Oriented (IFO) Induction Motor (IM). The IM drive can be controlled as a conventional prime mover in speed mode, or a wind turbine in torque-speed mode via robust observed torque control. This paper presents key issues for establishing a high-performance IFO IM drive. Further, this study develops a wind turbine load Interior Permanent-Magnet Synchronous Generator (IPMSG) followed by a three-phase Vienna Switch-Mode Rectifier (SMR). It receive [...]

by Oleksandr Skrylnyk  , Emilie Courbon  , Nicolas Heymans  and Marc Frère

Received: 18 December 2020;  Published: 14 April 2021;  doi: 10.21926/jept.2102017

Hybrid solar thermal systems are regarded as a promising solution for delivering clean thermal energy for building sector, especially when combining them with different renewable energy sources. Solar energy production usually does not match the thermal energy demand, and the energy storage must be integrated. Thermochemical energy storage is particularly adapted to be used with solar thermal applications. In this article, the design of the combined solar thermochemical energy storage system is demonstrated. The ex [...]

by Chen-Wei Yang  , Min-Ze Lu  , Wei-Ming Ma  and Chang-Ming Liaw

Received: 23 December 2020;  Published: 07 April 2021;  doi: 10.21926/jept.2102016

This paper presents a three-phase full-bridge boost switch-mode rectifier (SMR) fed switched-reluctance motor (SRM) drive with energy storage buffer. First, the power circuits and control schemes of the two power stages are properly designed. Except for having good line drawn power quality, the boostable DC-link voltage of the SRM drive can enhance the SRM driving performance in wide speed range. And the recovered regenerative braking energy can be sent back to the grid successfully. Then, a battery storage system [...]

by Anna Castaldo  , Emilia Gambale  and Giuseppe Vitiello

Received: 19 January 2021;  Published: 02 April 2021;  doi: 10.21926/jept.2102015

Zinc silicates thin films have been obtained by a solid state two steps reaction, consisting in the sputtering deposition of alternating layers of Silicon and Zinc oxide reagents, followed by their annealing carried out at temperatures ranging from 300° to 560 °C, in air or under vacuum. Transparent and chemically stable amorphous orto- and meta- Zinc silicates, respectively Zn2SiO4 and ZnSiO3 , can guest nanoaggregates of reagents (Silicon and/or ZnO ) depending on a careful modulation of the reaction advancement. [...]

by Shih-Ang Hsu

Received: 21 December 2020;  Published: 24 March 2021;  doi: 10.21926/jept.2101014

In order to improve offshore wind power operation and maintenance (O&M), particularly during tropical and non-tropical cyclones, short-term forecasts or nowcasts up to 6 hours of meteorological and oceanographic (met-ocean) parameters including wind, waves, currents and turbulence intensity are needed. On the basis of numerous air-sea and wind-wave interaction experiments, datasets are analyzed including those from simultaneous measurements of wind and waves during Hurricane Wilma. Formulas are presented for nowcas [...]

by Peter Leary  and Peter Malin

Received: 30 November 2020;  Published: 19 March 2021;  doi: 10.21926/jept.2101013

In interest of accurately modelling wellbore production in convective geothermal systems, we draw attention to two approaches to numerical simulation of crustal fluid flow. The historical ‘’strong’’ approach simulates the fluid mass conservation condition on a localised finite difference mesh approximation to poroelastic continua. The more flexible ‘’weak’’ approach globally enforces fluid mass conservation by in effect integrating over all numerical mesh cells. Strong formulation crustal flow simulation emerged fr [...]

by Aurore Raoux  , Ilan Robin  , Jean-Philippe Pezy  , Anne-Claire Bennis  and Jean-Claude Dauvin

Received: 08 October 2020;  Published: 17 March 2021;  doi: 10.21926/jept.2101012

The French coast of the Atlantic and English Channel (EC) is promising for the development of Marine Renewable Energy (MRE), including wind, wave, and tidal stream, due to the high velocity of currents in some parts of the area. This paper, focusing on wind and tidal energy, discusses how the implementation of MRE converters influences biodiversity, and vice versa, through biofouling and reef effects. The understanding of these interactions requires the knowledge of the hydro-sedimentary conditions and the macrofau [...]