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Im August 1997 wurde an Bord des FFS „Walther Herwig“ ein Eislagerversuch mit Kabeljau aus der Barebtssee durchgeführt. Die Fische wurden in täglichem Abstand auf ihre chemischen, physikalischen, sensorischen und mikrobiologischen Eigenschaften hin untersucht. Die analytischen Daten wurden jeweils mit den Tagen in Eis korreliert. Es erwies sich, daß die Werte vom Fischtester VI sowie RT Frischetester, von Dimethylamin- und Trimethylaminoxidstickstoff, die Qualitätseinstufung anhand des EUQualitätsbewertungsschemas, die sensorische Bewertung von gegarten Filetproben und die Gesamtkeimzahl auf der Haut am besten mit den im Eis verbrachten Tagen korrelierten. Die guteKorrelation zwischen sensorischen und instrumentell ermittelten Daten läßt in gewissem Umfang einen Ersatz von Sensorikdaten durch instrumentell ermittelten zu.

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A new idea of drag reduction and thermal protection for hypersonic vehicles is proposed based on the combination of a physical spike and lateral jets for shock-reconstruction. The spike recasts the bow shock in front of a blunt body into a conical shock, and the lateral jets work to protect the spike tip from overheating and to push the conical shock away from the blunt body when a pitching angle exists during flight. Experiments are conducted in a hypersonic wind tunnel at a nominal Mach number of 6. It is demonstrated that the shock/shock interaction on the blunt body is avoided due to injection and the peak pressure at the reattachment point is reduced by 70% under a 4A degrees attack angle.

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In this paper, multi-hole cooling is studied for an oxide/oxide ceramic specimen with normal injection holes and for a SiC/SiC ceramic specimen with oblique injection holes. A special purpose heat transfer tunnel was designed and built, which can provide a wide range of Reynolds numbers (10(5)similar to 10(7)) and a large temperature ratio of the primary flow to the coolant (up to 2.5). Cooling effectiveness determined by the measured surface temperature for the two types of ceramic specimens is investigated. It is found that the multi-hole cooling system for both specimens has a high cooling efficiency and it is higher for the SiC/SiC specimen than for the oxide/oxide specimen. Effects on the cooling effectiveness of parameters including blowing ratio, Reynolds number and temperature ratio, are studied. In addition, profiles of the mean velocity and temperature above the cooling surface are measured to provide further understanding of the cooling process. Duplication of the key parameters for multi-hole cooling, for a representative combustor flow condition (without radiation effects), is achieved with parameter scaling and the results show the high efficiency of multi-hole cooling for the oblique hole, SiC/SiC specimen. (C) 2008 Elsevier Ltd. All rights reserved.