Browsing by Author "Watson, James W."

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    Advancement in design and failure analysis of aluminium foam-filled honeycomb crash absorbers
    (Springer, 2023-03-01) Valente, Goncalo; Ghasemnejad, Hessam; Srimanosaowapak, S.; Watson, James W.
    Honeycomb structures are frequently used as energy absorption devices in the automotive and aerospace industry. Many studies have been conducted to optimise these structures and improve crashworthiness behaviour. This paper attempts to improve the crashworthiness behaviour of a honeycomb crash box by filling the cells with open-cell aluminium foams. Experimental tests were conducted to develop the honeycomb and aluminium foam material model and, also, to validate the finite element model by experimental data. The finite element model was developed in ABAQUS, and different variables were parameterised to aim a quick implementation. The empty aluminium honeycomb crash box is used as a term of comparison with the foam-filled ones. Foam-filling the crash box allows the control of the densification zone for different impact energies using open-cell aluminium foam, which shows the main novelty of this research. In the end, the optimised structure is presented concerning the optimum number of foam-filled cells and, also, to the aluminium foam’s density that best fits this application.
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    Cost of Physical Vehicle Crash Testing
    (2008-12-31T00:00:00Z) Baguley, Paul; Roy, Rajkumar; Watson, James W.
    The automotive safety-testing environment currently deploys virtual methods and physical crash testing for new product development and validation in safety testing legislation. Cost benefit analysis of crash testing is considered here by estimating the cost of physical crash testing. This has been achieved via the compilation of detailed process maps and AS-IS analyses of the current physical testing procedures. This leads on to detailed work and cost breakdown structures used in the comparative analysis of cost drivers. The consideration of cost drivers at several stages of the New Product Development process aids Concurrent Engineering. This research considers front and side impact only.
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    Developed trigger mechanisms to improve crush force efficiency of aluminium tubes
    (Elsevier, 2019-09-11) Rai, V.; Ghasemnejad, Hessam; Watson, James W.; Gonzalez-Domingo, J. A.; Webb, Phil
    This paper aims to investigate the effect of a trigger mechanism on the crush force efficiency of aluminium tubular absorbers. Various trigger mechanisms such as cut-out holes, circumferential notch and end-fillet, were studied using the validated numerical model. Initially, tubes made of aluminium displayed better crashworthiness behaviour when compared with steel tubes based on numerical and experimental results. Then the trigger mechanism consisting of three cut-out holes was found more efficient than the ones with an end fillet and a circumferential notch based on a comparative study. According to these results, the developed trigger mechanisms have a significant change in crashworthiness performance of tubular absorbers. Crush force efficiency was doubled with the help of this trigger mechanism while stroke efficiency and specific energy absorptions were reduced by 4% and 15% respectively.