A carregar...
Publicação
Development and Construction of a Composite Battery Container for Formula Student Vehicle
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 52.46 MB | Adobe PDF |
Autores
Orientador(es)
Resumo(s)
Este trabalho apresenta o desenvolvimento e construção de um contentor para os
módulos de alta tensão (TSAC - Tractive System Accumulator Container) em material
compósito para o protótipo elétrico da Formula Student da equipa LART (Leiria
Academic Racing Team), com o objetivo de redução de massa em 40% face ao design
anterior, cumprindo os regulamentos da competição, os requisitos de integridade estrutural
e as restrições de manutenção.
O processo de design seguiu uma metodologia estruturada em três fases: dimensionamento
analítico com base na teoria de placas e na Teoria Clássica dos Laminados,
validação numérica por análise de elementos finitos, e a caracterização experimental
do sistema de materiais selecionado. Foi adotado um compósito de aramida
com resina Sika Biresin CR132FR, pela combinação de desempenho estrutural, isolamento
elétrico, resistência ao fogo e acessibilidade de fabrico. Um laminado uniforme
[0/90]16 foi adotado em todos os painéis para simplificar a produção.
O dimensionamento analítico identificou a tensão de corte da cola como o critério
dominante para a maioria dos painéis. Os modelos de elementos finitos demonstraram
que a formulação de deflexão pequena constitui uma fase conservadora, e revelaram
que a formulação de deflexão grande é não conservadora para tensões em condições
ortotrópicas. Os modelos em condições reais destacaram as tensões de corte da cola
como a limitação crítica da abordagem analítica sob concentrações localizadas, sendo
isto resolvido pelo laminado uniforme adotado.
A validação experimental confirmou as propriedades do material através de ensaios
de tração, densidade, flexão em três pontos e corte por perimetro. O laminado
[0/90]16 demonstrou uma resistência à flexão de 281 MPa e uma resistência ao corte de
169 MPa - três vezes superior ao valor analítico assumido. Os ensaios de flamabilidade
confirmaram a conformidade UL94 V-0.
O TSAC construido atingiu uma massa total de 9,15 kg, representando um excesso
de 0,69 kg face ao objetivo de 8,46 kg. Este resultado vai de encontro às decisões
tomadas durante a fase de design para garantir o cumprimento do regulamento, a
fiabilidade estrutural e a facilidade de produção, em particular a adoção do laminado
uniforme [0/90]16.
This work presents the development and construction of a composite Tractive System Accumulator Container (TSAC) for the LART Formula Student electric race car, targeting a 40% mass reduction relative to the previous metallic enclosure while satisfying competition regulations, structural integrity requirements, and serviceability constraints. The design followed a structured three-stage methodology: analytical dimensioning based on classical plate theory and Classical Lamination Theory, numerical validation through finite element analysis, and experimental material characterisation. A wet lay-up aramid composite with Sika Biresin CR132FR resin was selected for its combination of structural performance, electrical insulation, fire retardancy, and manufacturing accessibility, with a uniform [0/90]16 layup adopted across all panels. Analytical dimensioning identified adhesive shear as the governing design criterion for most panels. Finite element models confirmed the conservatism of small deflection theory while revealing that the large deflection formulation is non-conservative for stress in orthotropic laminates. Real condition models further highlighted adhesive shear under localised loading as a critical limitation of the analytical approach, resolved by the uniform layup. Full assembly simulation confirmed structural adequacy under X and Z− loading. Experimental validation confirmed the material properties through tensile, density, three-point bending, and perimeter shear tests. The [0/90]16 laminate demonstrated a flexural strength of 281 MPa and a shear strength of 169 MPa providing substantial safety margins beyond the regulatory minimum. Flammability tests confirmed UL94 V-0 compliance for the selected material system. The completed TSAC achieved a measured total mass of 9.15 kg, representing an excess of 0.69 kg relative to the 8.46 kg target. This result reflects the design decisions taken to ensure regulatory compliance, structural reliability, and manufacturing feasibility - in particular the adoption of the uniform [0/90]16 layup. The project additionally established in-house composite manufacturing capabilities within the team, laying the groundwork for future application of composite materials to other structural components.
This work presents the development and construction of a composite Tractive System Accumulator Container (TSAC) for the LART Formula Student electric race car, targeting a 40% mass reduction relative to the previous metallic enclosure while satisfying competition regulations, structural integrity requirements, and serviceability constraints. The design followed a structured three-stage methodology: analytical dimensioning based on classical plate theory and Classical Lamination Theory, numerical validation through finite element analysis, and experimental material characterisation. A wet lay-up aramid composite with Sika Biresin CR132FR resin was selected for its combination of structural performance, electrical insulation, fire retardancy, and manufacturing accessibility, with a uniform [0/90]16 layup adopted across all panels. Analytical dimensioning identified adhesive shear as the governing design criterion for most panels. Finite element models confirmed the conservatism of small deflection theory while revealing that the large deflection formulation is non-conservative for stress in orthotropic laminates. Real condition models further highlighted adhesive shear under localised loading as a critical limitation of the analytical approach, resolved by the uniform layup. Full assembly simulation confirmed structural adequacy under X and Z− loading. Experimental validation confirmed the material properties through tensile, density, three-point bending, and perimeter shear tests. The [0/90]16 laminate demonstrated a flexural strength of 281 MPa and a shear strength of 169 MPa providing substantial safety margins beyond the regulatory minimum. Flammability tests confirmed UL94 V-0 compliance for the selected material system. The completed TSAC achieved a measured total mass of 9.15 kg, representing an excess of 0.69 kg relative to the 8.46 kg target. This result reflects the design decisions taken to ensure regulatory compliance, structural reliability, and manufacturing feasibility - in particular the adoption of the uniform [0/90]16 layup. The project additionally established in-house composite manufacturing capabilities within the team, laying the groundwork for future application of composite materials to other structural components.
Descrição
Palavras-chave
Materiais compósitos Aramida Contentor de bateria Fórmula Student Teoria de Laminado Clássico Análise de elementos finitos Design estrutural