HighlightsDeep sequencing has potential as an improved adventitious virus screening method.15 laboratories sequenced a common reagent containing 25 target viruses.6 viruses were detected by all lab, the remainder were detected by 4–14 labs.A wide range of sample preparation and bioinformatics methods is currently used.A common reference material is essential to enable results to be compared.

The near-field behavior of a tip vortex trailing behind a low aspect ratio wing, attached to an axisymmetric body, is investigated in this paper. This study was performed in a tow tank and involved the use of particle displacement velocimetry. Evolution of the tip vortex was studied by mapping its instantaneous lateral velocity at several consecutive axial locations. The axial velocity distribution was also measured. Experiments were repeated at various Reynolds numbers and incidence angles. Repeatability was also examined at the same conditions. The results indicate that roll-up is almost complete at the trailing edge and that less than 66% of the root circulation is entrained into the vortex. At Re c = 2.2 x 10 s , the results are steady, and the spatially averaged tangential velocity agrees well with the existing models. At Re c

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Particle displacement velocimetry is used to measure the velocity and vorticity distributions around an inclined 6: 1 prolate spheroid. The objective is to determine the effects of boundary-layer tripping, incidence angle, and Reynolds number on the flow structure. The vorticity distributions are also used for computing the lateral forces and rolling moments that occur when the flow is asymmetric. The computed forces agree with results of direct measurements. It is shown that when the flow is not tripped, separation causes the formation of a pair of vortex sheets. The size of these sheets increases with increasing incidence angle and axial location. Their orientation and internal vorticity distribution also depend on incidence. Rollup into distinct vortices occurs in some cases, and the primary vortex contains between 20 % and 50 % of the overall circulation. The entire flow is unsteady and there are considerable variations in the instantaneous vorticity distributions. The remainder of the lee side, excluding these vortex sheets, remains almost vorticity free, providing clear evidence that the flow can be characterized as open separation. Boundary-layer tripping causes earlier separation on part of the model, brings the primary vortex closer to the body, and spreads the vorticity over a larger region. The increased variability in the vorticity distribution causes considerable force fluctuations, but the mean loads remain unchanged. Trends with increasing Reynolds number are conflicting, probably because of boundary-layer transition. The separation point moves towards the leeward meridian and the normal force decreases when the Reynolds number is increased from 0.42 × 106 to 1.3 × 106. Further increase in the Reynolds number to 2.1 × 106 and tripping cause an increase in forces and earlier separation.

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