Otimização multiobjetivo de um casco de veleiro através de uma abordagem integrada aero-hidrodinâmica

TCC (graduação) - Universidade Federal de Santa Catarina. Campus Joinville. Engenharia Naval.Este estudo apresenta o desenvolvimento de uma metodologia para o projeto de veleiros através de uma abordagem focada na melhora das dimensões e curvaturas do casco. A primeira etapa é a criação de um modelo paramétrico da superfície do casco, composto por curvas definidas por parâmetros específicos, que descrevem com simplicidade e precisão o formato do casco. Este processo é conduzido utilizando-se o programa CAESES®. Os componentes hidrodinâmicos e aerodinâmicos são inseridos na análise através do uso do programa Star-CCM+®. Neste, o casco gerado anteriormente é acoplado a modelagem da vela, que juntos compõe o objeto de análise aplicado a uma dada condição de vento e mar. Ao final, tem-se a velocidade desempenhada pelo veleiro para certas condições externas. Além da velocidade final desempenhada, o seakeeping também é analisado através dos índices MSI – Motion Sickness Incidence e SM – Subjective Motion. Tanto a velocidade final quanto o resultado do MSI e SM serão os objetivos do modelo, que emprega Redes Neurais Artificiais e técnicas de otimização direcionadas a maximizar a velocidade e minimizar os índices de seakeeping. Ao final do projeto, obtém-se não apenas uma melhoria do casco analisado, tanto em termos de seakeeping quanto de velocidade, apresentando uma melhoria de 2,68% no primeiro e 20% no segundo. Porém, mais relevante ainda é a contribuição para um entendimento mais vasto sobre a aplicação de uma metodologia integrada para análise simultânea dos aspectos hidrodinâmicos e aerodinâmicos de forma ágil, precisa e robusta

Estimating CO2 emissions for 108 000 European cities

Abstract. City-level CO2 emissions inventories are foundational for supporting the EU's decarbonization goals. Inventories are essential for priority setting and for estimating impacts from the decarbonization transition. Here we present a new CO2 emissions inventory for all 116 572 municipal and local-government units in Europe, containing 108 000 cities at the smallest scale used. The inventory spatially disaggregates the national reported emissions, using nine spatialization methods to distribute the 167 line items detailed in the National Inventory Reports (NIRs) using the UNFCCC (United Nations Framework Convention on Climate Change) Common Reporting Framework (CRF). The novel contribution of this model is that results are provided per administrative jurisdiction at multiple administrative levels, following the region boundaries defined OpenStreetMap, using a new spatialization approach. All data from this study are available on Zenodo https://doi.org/10.5281/zenodo.5482480 (Moran, 2021) and via an interactive map at https://openghgmap.net (last access: 7 February 2022​​​​​​​)

openghgmap.net - Estimating CO2 Emissions for 108,000 European Cities

<p>City-level CO2 emissions inventories are foundational for supporting the EU’s decarbonization goals. Inventories are essential for priority setting and for estimating impacts from the decarbonization transition. Here we present a new CO2 emissions inventory for all 116,572 municipal and local government units in Europe, containing 108,000 cities at the smallest scale used. The inventory spatially disaggregates the national reported emissions, using 9 spatialization methods to distribute the 167 line items detailed in the National Inventory Reports (NIRs) using the UNFCCC Common Reporting Framework (CRF). The novel contribution of this model is that results are provided per administrative jurisdiction at multiple administrative levels, following the region boundaries defined OpenStreetMap, using a new spatialization approach. Project website: openghgmap.net</p&gt

Development of a tool for parametric optimization of hydrodynamic resistance of sailing yachts through the Delft series.

A avaliação do desempenho de veleiros tem sido realizada por projetistas e arquitetos navais desde o início da navegação através da experiência adquirida e experimentação. A base científica cresceu partindo da identificação dos fatores-chave que mais influenciam o desempenho, como comprimento, boca, deslocamento, para uma compreensão muito mais robusta da complexidade inerente às forças e momentos envolvidos no sistema de equilíbrio que compõe um veleiro. Recentemente, o aumento no poder computacional tornou possível realizar essa avaliação de forma sistemática. Isso inclui o cálculo detalhado de forças para prever o comportamento de um veleiro e, finalmente, seu desempenho sob diferentes condições de operação. Portanto, o objetivo deste estudo foi estabelecer uma metodologia para analisar o desempenho de veleiros em águas calmas e ondas usando a série sistemática de Delft para estimar as forças hidrodinâmicas envolvidas. As forças calculadas são integradas a algoritmos genéticos buscando investigar alternativas para as dimensões do casco a fim de minimizar as forças hidrodinâmicas totais. Por último, essa metodologia é incorporada à uma ferramenta disponibilizada online destinada a avaliar o desempenho de veleiros à vela em uma ampla gama de condições do mar.The evaluation of the performance of sailing yachts has been carried out by naval architects since the very beginning of sailing through experience and experimenting. The scientific basis has grown from identifying key factors that influence performance the most, such as length, beam, displacement, to a much more complete understanding of the inherent complexity in forces and coupling moments involved in the equilibrium system of sailing yachts.In recent years, the advent of computers has made it possible to perform this assessment in a systematic manner. This includes the detailed calculation of forces to predict the behavior of a sailing yacht and ultimately its performance under different conditions of operation. Therefore, the aim of this study was to establish a methodology to analyze the performance of sailing yachts in calm waters and waves using the Delft Systematic Yacht Hull Series to estimate the hydrodynamic forces involved. The forces calculate are coupled with a genetic algorithm to investigate alternative solutions of hull dimensions in order to minimize total hydrodynamic forces. Ultimately, this methodology is incorporated into an online tool capable of assessing the performance of sailing yachts in a wide range of sea states

Global Shipping Emissions from a Well-to-Wake Perspective: The MariTEAM Model

Improving the robustness of maritime emission inventories is important to ensure we fully understand the point of embarkment for transformation pathways of the sector toward the 1.5 and 2°C targets. A bottom-up assessment of emissions of greenhouse gases and aerosols from the maritime sector is presented, accounting for the emissions from fuel production and processing, resulting in a complete “well-to-wake” geospatial inventory. This high-resolution inventory is developed through the use of the state-of-the-art data-driven MariTEAM model, which combines ship technical specifications, ship location data, and historical weather data. The CO2 emissions for 2017 amount to 943 million tonnes, which is 11% lower than the fourth International Maritime Organization’s greenhouse gas study for the same year, while larger discrepancies have been found across ship segments. If fuel production is accounted for when developing shipping inventories, total CO2 emissions reported could increase by 11%. In addition to fuel production, effects of weather and heavy traffic regions were found to significantly impact emissions at global and regional levels. The global annual efficiency for different fuels and ship segments in approximated operational conditions were also investigated, indicating the need for more holistic metrics than current ones when seeking appropriate solutions aiming at reducing emissions

Global Shipping Emissions from a Well-to-Wake Perspective: The MariTEAM Model

Improving the robustness of maritime emission inventories is important to ensure we fully understand the point of embarkment for transformation pathways of the sector toward the 1.5 and 2°C targets. A bottom-up assessment of emissions of greenhouse gases and aerosols from the maritime sector is presented, accounting for the emissions from fuel production and processing, resulting in a complete “well-to-wake” geospatial inventory. This high-resolution inventory is developed through the use of the state-of-the-art data-driven MariTEAM model, which combines ship technical specifications, ship location data, and historical weather data. The CO2 emissions for 2017 amount to 943 million tonnes, which is 11% lower than the fourth International Maritime Organization’s greenhouse gas study for the same year, while larger discrepancies have been found across ship segments. If fuel production is accounted for when developing shipping inventories, total CO2 emissions reported could increase by 11%. In addition to fuel production, effects of weather and heavy traffic regions were found to significantly impact emissions at global and regional levels. The global annual efficiency for different fuels and ship segments in approximated operational conditions were also investigated, indicating the need for more holistic metrics than current ones when seeking appropriate solutions aiming at reducing emissions

Island geography shaping maritime space in Macaronesia

This paper explores how geography shapes human uses of the maritime space along the Atlantic archipelagic territories of Macaronesia, a biogeographical region that includes the archipelagos of the Azores, Madeira, Selvagens, Canary Islands and Cape Verde. The way specific geographic characteristics of these islands influence and even determine maritime uses and activities is analyzed in a three-layers ap proach in the following order: socio economic analysis, sectorial analysis and uses and activities analysis. The biophysical and geographical characteristics of each archipelago will be considered throughout the analysis, highlighting the common aspects and peculiarities between each region. After a comprehensive overview of the main economic activities, the discussion suggests that certain specificities need to be taken into account in maritime spatial planning processes when planning and managing human uses at sea, to promote the sustainable development of local communities, particularly in archipelagic regions