Shoulder disorders are very common in the older population. These can be traumatic injuries such as proximal humerus fractures, or degenerative pathology, with rotator cuff disease being the most frequently diagnosed. Lower functional demands along with the presence of co-morbidities means that conservative management is usual. However, surgery can provide pain relief and improve functional outcomes in selected patients. A thorough pre-operative assessment should be performed to avoid surgical or post-operative complications. Osteoporosis is the major concern when undertaking bone fixation in orthopaedic implants and should be routinely ruled out and treated in order to achieve better results.

In this study, a spray cooling device for electronic components was investigated. Dielectric fuid (FC-72) was sprayed at 50°C through five nozzles (4.243mm spacing). The nozzles are of diameters 0.17, 0.23 or 0.41mm. Volume flow rate varied from 24.5 to 99.1ml/min. Two grooved surfaces and a smooth surface were tested, and the heated area was 12 × 12mm2. The larger nozzles yielded greater heat transfer coefficients at high heat fluxes (300 ∼ 600kW/m2). However, smaller nozzles result in greater dry-out heat fluxes and greater heat transfer coefficients at heat flux < 300kW/m2. The C4 surface, having parallel grooves of 0.4mm depth, improved the spray cooling performance by up to 80% as compared with the smooth suface. Its thermal resistance is 0.11 ∼ 0.12K/W at 99.1ml/min flow rate, in the range of 85 ∼ 130W heat input. A new correlation of spray cooling, accounting for the contributions of nucleate boiling and spray convection, is proposed. For data of FC-72 in the range of Re = 856 ∼ 6188, Bo = 0.19 ∼ 5.70, We = 25.2 ∼ 3541.3, the predicted h-values agree with experimental data of the smooth surface within ±25%.

Le développement du jet libre est relativement bien connu, ce n'est pas le cas du jet plan turbulent en présence d'un impact. En effet, selon la distance H de la paroi d'impact, et de l'épaisseur initiale e du jet, le développement se fera de manière relativement différente à cause du confinement qui conditionne l'expansion du jet. À la différence du jet libre, il n'existe pas à l'heure actuelle de base de données complète ni de modèle global permettant de décrire analytiquement la décroissance de la vitesse moyenne dans le plan de symétrie des jets plans en impact. La littérature fait bien état de lois semi-empiriques, mais les relations correspondantes ne concernent que quelques zones de la région de jet : le cône potentiel et la zone d'affinité principalement.Le travail présenté concerne d'une part, l'établissement d'une corrélation générale capable de décrire l'évolution de la vitesse axiale quelles que soient l'épaisseur du jet et la distance à l'impact, et d'autre part, la description du champ de turbulence du jet et les lois d'épanouissement latéral. Les résultats du modèle de décroissance de la vitesse axiale sont aussi comparés et validés à l'aide de mesures expérimentales obtenues par vélocimétrie laser à effet Doppler.

Experiments for heat transfer characteristics of confined circular single jet impingement were conducted. The effect of jet Reynolds number, jet hole-to-plate spacing and heat flux levels on heat transfer characteristics of the heated target surface was examined and presented. The local heat transfer coefficient along the surface is measured and correlations of the stagnation point, local and average Nusselt number are developed and discussed. Finally, comparisons of the present data with existing results were also made.