{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:28:02Z","timestamp":1760236082473,"version":"build-2065373602"},"reference-count":59,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,10,29]],"date-time":"2021-10-29T00:00:00Z","timestamp":1635465600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Interreg Atlantic Area Programme through the European Regional Development Fund","award":["EAPA 784\/2018"],"award-info":[{"award-number":["EAPA 784\/2018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Inventions"],"abstract":"<jats:p>Despite several wave energy converters (WECs) having been developed to present, no particular concept has emerged yet. The existing inventions vary significantly in terms of the operation principle and complexity of WECs. The tethered point absorbers (PAs) are among the most known devices that, thanks to their simplicity, appear to be cost-effective and reliable for offshore installation. These devices need to be advanced further and, therefore, new tailored modelling methods are required. Numerical modelling of this type of WEC has been done mainly in one degree of freedom. Existing methods for multi-degrees of freedom analysis lack pragmatism and accuracy. Nevertheless, modelling of multiple degrees of freedom is necessary for correct analysis of the device dynamic response, wave loads and device performance. Therefore, an innovative numerical method for two degrees of freedom analysis of PA WECs, which permits precisely modelling the dynamics of PA for surge and heave motions, is introduced in this paper. The new method allows assessing, in the time-domain, the dynamic response of tethered PAs using regular and irregular sea states. The novel numerical model is explained, proved and empirically validated.<\/jats:p>","DOI":"10.3390\/inventions6040075","type":"journal-article","created":{"date-parts":[[2021,11,2]],"date-time":"2021-11-02T22:14:52Z","timestamp":1635891292000},"page":"75","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Novel 2-D Point Absorber Numerical Modelling Method"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0930-6658","authenticated-orcid":false,"given":"Gianmaria","family":"Giannini","sequence":"first","affiliation":[{"name":"Department of Civil Engineering, Faculty of Engineering of the University of Porto (FEUP), 4200-465 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research of the University of Porto (CIIMAR), 4200-465 Porto, Portugal"}]},{"given":"Sandy","family":"Day","sequence":"additional","affiliation":[{"name":"Department of Naval Architecture, Ocean and Marine Engineering, University of Strathclyde, Glasgow G4 0LZ, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3768-3314","authenticated-orcid":false,"given":"Paulo","family":"Rosa-Santos","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Faculty of Engineering of the University of Porto (FEUP), 4200-465 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research of the University of Porto (CIIMAR), 4200-465 Porto, Portugal"}]},{"given":"Francisco","family":"Taveira-Pinto","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Faculty of Engineering of the University of Porto (FEUP), 4200-465 Porto, Portugal"},{"name":"Interdisciplinary Centre of Marine and Environmental Research of the University of Porto (CIIMAR), 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"296","DOI":"10.1016\/j.renene.2012.01.101","article-title":"Quantifying the global wave power resource","volume":"44","author":"Gunn","year":"2012","journal-title":"Renew. 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