A three-dimensional code for rotating blade-row flow analysis has been developed. The space discretization uses a cell-centered scheme with eigenvalues scaling for the artificial dissipation. The computational efficiency of a four-stage Runge-Kutta scheme is enhanced by using variable coefficients, implicit residual smoothing, and a full-multigrid method. An application is presented for the NASA rotor 67 transonic fan. Due to the blade stagger and twist, a zonal, non-periodic H-type grid is used to minimize the mesh skewness. The calculation is validated by comparing it with experiments in the range from the maximum flow rate to a near-stall condition. A detailed study of the flow structure near peak efficiency and near stall is presented by means of pressure distribution and particle traces inside boundary layers.

Parent stocks of meat birds are severely feed restricted to avoid obesity-related health and fertility problems. This restriction often leads to chronic hunger, accompanied by stereotypic behavior. Research based in the United Kingdom has shown that using diets containing fiber and appetite suppressants may relieve some of the symptoms of hunger. However, few data are available regarding North American-sourced ingredients or nondaily feeding regimens. This study investigated the effects of 2 alternative diets, in combination with 2 feeding frequencies on growth, productivity, and behavior in broiler breeders. Six dietary treatments were tested, each with 5 replicate pens of 12 or 13 birds. Control diets consisted of a commercial crumble, fed on a daily or skip-a-day (SAD) basis. Alternative diets included soybean hulls as a fiber source, and calcium propionate as an appetite suppressant of either a feed-grade or purified quality, fed on either a daily or SAD basis. Birds were weighed weekly and egg production was recorded daily. Video cameras were used to record behavior during and following the morning feeding bout every 2 wk from 11 to 28 wk. Data were analyzed with a mixed model ANOVA, with repeated measures. Diet, feeding frequency, time, or an interaction of the 3 had significant effects on all observed behavior during rearing. These differences appeared to diminish during lay, with most stereotypic behavior no longer present. Very little object pecking and aggression was observed during and immediately following feeding bouts; however, daily-fed control birds still displayed this behavior more often, especially during rearing (P = 0.015). During feeding bouts, SAD birds feather pecked (P = 0.003) and rested more (P = 0.0002) than daily-fed birds. Control birds feather pecked most often (P = 0.033) after feeding bouts. Overall, the feed-grade diet appeared most effective at reducing hunger-related behavior, and the control diet appeared the least effective. There was little conclusive evidence to show that daily feeding was more effective at reducing hunger.

A new kind of C-type grid is proposed for turbomachinery flow calculations. This grid is nonperiodic on the wake and results in minimum skewness for cascades with high turning and large camber. The Reynoldsaveraged Navier-Stokes equations are discretized on this type of grid using a finite volume approach. The Baldwin-Lomax eddy-viscosity model is used for turbulence closure. Jameson's explicit Runge-Kutta scheme is adopted for the integration in time, and computational efficiency is achieved through accelerating strategies such as multigriding and residual smoothing. A detailed numerical study has been carried out for a turbine rotor and for a vane. A grid dependence analysis is presented and the effect of the artificial dissipation is also investigated. Comparison of calculations with experiments clearly demonstrate the advantage of the proposed grid.

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