To explore the potential role that load-induced fluid flow plays as a mechano-transduction mechanism in bone adaptation, a lacunar-canalicular scale bone poroelasticity model is developed and implemented. The model uses micromechanics to homogenize the pericanalicular bone matrix, a system of straight circular cylinders in the bone matrix through which bone fluids can flow, as a locally anisotropic poroelastic medium. In this work, a simplified two-dimensional model of a periodic array of lacunae and their surrounding systems of canaliculi is used to quantify local fluid flow characteristics in the vicinity of a single lacuna. When the cortical bone model is loaded, microscale stress, and strain concentrations occur in the vicinity of individual lacunae and give rise to microscale spatial variations in the pore fluid pressure field. Furthermore, loading of the bone matrix containing canaliculi generates fluid pressures in the contained fluids. Consequently, loading of cortical bone induces fluid flow in the canaliculi and exchange of fluid between canaliculi and lacunae. For realistic bone morphology parameters, and a range of loading frequencies, fluid pressures and fluid-solid drag forces in the canalicular bone are computed and the associated energy dissipation in the models compared to that measured in physical in vitro experiments on human cortical bone. The proposed model indicates that deformation-induced fluid pressures in the lacunar-canalicular system have relaxation times on the order of milliseconds as opposed to the much shorter times (hundredths of milliseconds) associated with deformation-induced pressures in the Haversian system.

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Delamination has been identified as one of the most deleterious damage processes associated with drilling fiber reinforced plastics (FRPs) due to the resulting drastic reduction of structural strength and stiffness. In recent years, several experimental, numerical, and analytical studies have been conducted aimed at understanding delamination initiation and progression during drilling. In this study, a comprehensive review of existing analytical studies has been presented comparing and contrasting their respective advantages and disadvantages. Special emphasis has been laid upon presenting all assumptions made and the underlying implications thereby. Suggestions at improving the existing models so as to facilitate a more realistic description of the drill process using composite lamination theories have also been included.

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In present work, abrasive waterjet machining has been used to machine adhesively bonded titanium-carbon fiber-reinforced plastics-titanium hybrid laminate with varying traverse speed, jet pressure, and stand-off distance. The effect of varying abrasive waterjet machining parameters on cut quality has been quantified by material removal rate, metal composite interface damage factor, taper ratio ( T r), and surface roughness (Ra). Response surface methodology along with central composite design has been used to analyze the influence of process parameters on output responses. Additionally, analysis of variance was performed to identify the significant parameters on the output responses. For better abrasive waterjet cut quality, the optimal values of process parameters obtained were 200 MPa jet pressure, 237.693 mm/min traverse speed, and 1 mm stand-off distance. The corresponding material removal rate, metal composite interface damage factor, taper ratio, and surface roughness are 5.388 mm3/s, 1.41, 1.16, and 3.827 µm, respectively. Furthermore, validation tests have been performed with obtained optimal parameters that deliver satisfactory outcomes with an error of 5.35%, 3.07%, 2.29%, and 0.39% for material removal rate, metal composite interface damage factor, taper ratio, and surface roughness, respectively.

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The present work focuses on the formulation of transient incompressible resin flow during vacuum-assisted resin transfer moulding using level set front tracking method in a multi-block structured grid within a finite difference framework. Initially, the relation between compaction pressure and fibre volume fraction ([Formula: see text]) has been established by conducting compression tests using a universal tensile machine under dry and wet conditions. In-plane permeability has been characterised as a function of [Formula: see text] using three thicknesses of unidirectional carbon fabric (4, 8 and 12 plies). A pressure data acquisition system and a non-contact out-of-plane displacement measurement setup have been developed using a single lens camera to conduct the vacuum infusion experiments. The numerical model prediction of the instantaneous change in pressure, displacement, and fill time has been validated with the experiments for the three different thickness of unidirectional preform in a flat plate and a plate with a centrally located hole during vacuum infusion. The coupled transient flow model with the level set interface propagation in a multi-block framework shows a good agreement with vacuum infusion experiments. The proposed transient vacuum infusion flow model, compaction relation with [Formula: see text], permeability and experimental setup show the potential to capture realistic flow physics during vacuum infusion on different mould configurations.