Backsheet is the outermost layer of the photovoltaic (PV) laminate which consists of polymers such as Polyethylene terephthalate (PET) or Polyvinyl fluoride (PVF). The viscoelastic response of these materials significantly affects the durability of the PV module. In this study, the viscoelastic response of commercially available backsheet materials is experimentally characterized and computationally modeled. An extensive viscoelastic experimental study on backsheet materials is carried out, considering the temperature-dependent properties to characterize the mechanical properties. Based on an experimental campaign, small-strain viscoelastic models based on the Prony-series (PS) and Fractional Calculus (FC) are herein proposed. The form of the constitutive equations for both models is outlined, and the finite element implementation is described in detail. Following the identification of the relevant material parameters, models are validated with experimental data, showing good predictability. A comparative study of model responses under different loading conditions is also reported to assess the advantages and disadvantages of both models. Such an extensive experimental study and constitutive modeling will help design and simulate a more comprehensive digital-twin model of PV modules, as illustrated by the benchmark problems.

Computational modeling of viscoelastic backsheet materials for photovoltaics

Lenarda, P.
Membro del Collaboration Group
;
Paggi, M.
Membro del Collaboration Group
2023-01-01

Abstract

Backsheet is the outermost layer of the photovoltaic (PV) laminate which consists of polymers such as Polyethylene terephthalate (PET) or Polyvinyl fluoride (PVF). The viscoelastic response of these materials significantly affects the durability of the PV module. In this study, the viscoelastic response of commercially available backsheet materials is experimentally characterized and computationally modeled. An extensive viscoelastic experimental study on backsheet materials is carried out, considering the temperature-dependent properties to characterize the mechanical properties. Based on an experimental campaign, small-strain viscoelastic models based on the Prony-series (PS) and Fractional Calculus (FC) are herein proposed. The form of the constitutive equations for both models is outlined, and the finite element implementation is described in detail. Following the identification of the relevant material parameters, models are validated with experimental data, showing good predictability. A comparative study of model responses under different loading conditions is also reported to assess the advantages and disadvantages of both models. Such an extensive experimental study and constitutive modeling will help design and simulate a more comprehensive digital-twin model of PV modules, as illustrated by the benchmark problems.
2023
Prony series model
Fractional calculus model
Creep
Relaxation modulus
Linear viscoelasticity
File in questo prodotto:
File Dimensione Formato  
1-s2.0-S0167663623002569-main.pdf

accesso aperto

Tipologia: Versione Editoriale (PDF)
Licenza: Creative commons
Dimensione 5.42 MB
Formato Adobe PDF
5.42 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11771/27718
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
social impact