Research Papers - Department of Civil Engineering

Permanent URI for this collectionhttps://rda.sliit.lk/handle/123456789/598

Browse

Filters

2009 - 200912010 - 20151

Advanced Search

Filter by

Settings

Subject: search.filters.subject.Finite element analysis

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    PublicationEmbargo
    Performance of piezoelectric actuators in a hydrogen environment: Experimental study and finite element modelling
    (Pergamon, 2015-03-02) Singh, Y; Rajapakse, R. K. N. D; Kjeang, E; Mumford, D
    Significant improvements in fuel efficiency and emissions can be achieved in internal combustion engines (ICE) by electronically controlling the fuel injector opening valves with piezoelectric actuators. Hydrogen is considered an attractive alternative fuel with near-zero emissions at the point of use; however, the current understanding of the performance of piezoelectric actuators in a hydrogen environment is very limited. Variation in the performance of piezoelectric actuators due to their continuous and cyclic exposure to hydrogen at 100 °C and 10 MPa is experimentally investigated in the present work. The actuator's stroke-voltage relationship is evaluated under quasi-static as well as dynamic electric loading conditions within the ambient temperature range of 5–80 °C. A 3-D finite element model is also developed to simulate the behaviour of a single stack of an actuator exposed to hydrogen by using experimentally determined piezoelectric coefficients. The importance of coating technology to protect the actuator material from hydrogen is confirmed by the experimental study and numerical modelling.
  • Thumbnail Image
    PublicationEmbargo
    Modelling the high temperature behaviour of TBCs using sequentially coupled microstructural–mechanical FE analyses
    (Elsevier, 2009-07-15) Hermosilla, U; Karunaratne, M. S. A; Jones, I. A; Hyde, T. H; Thomson, R. C
    Thermal barrier coatings provide a means of thermal insulation of gas turbine components exposed to elevated temperatures. They undergo severe microstructural changes and material degradation, which have been implemented in this work by means of a sequentially coupled microstructural mechanical calculation that made use of a self-consistent constitutive model within finite element calculations. Analyses for different temperatures and bond coat compositions were run, which reproduced the trends reported in previous research and identified the accumulation of high out-of-plane tensile stresses within the alumina layer as an additional phenomenon that could drive high temperature crack nucleation.