Cavitation patterns on a plano-convex hydrofoil in a highspeed cryogenic cavitation tunnel

Cavitation around a plano-convex hydrofoil has been observed using a cryogenic cavitation tunnel of a blowdown type. An approximately 300mm long test section with flow visualization was set between the 100L upper and lower tanks. The working fluids were water and liquid nitrogen. Experiments with emphasis on periodical shedding of cloud cavitation were performed for three channels, 20, 30 and 60 mm in width, and two hydrofoils, 20 and 60mm in chord length LC. Inlet velocity uin and cavitation number ? were varied between 3.8 and 19.5 m/sec, and ?1.83 and 19.35, respectively. Incident angle was fixed at 8º. Observed cavitation patterns are sorted according to the maximum cavitation length Lmax compared to LC. Type X is defined as no cavitation, type A as 02LC. Type B has either the periodical shedding mode or the steady mode, so type PB is defined as type B with periodical shedding and type SB as type B under steady condition. Apparently types A and C are almost steady. Type PB solely occurs in the case that Lmax is comparable to LC. The cavitation patterns are mapped in the diagram of the degree of subcooling Pin?Psat versus the dynamic pressure ?uin2/2 because they are not organized only by ? =(Pin?Psat )/(?uin2/2). It is suggested that the maximum cavitation thickness is controlled by the similarity laws of hydrofoils for types SB and C.http://deepblue.lib.umich.edu/bitstream/2027.42/84257/1/CAV2009-final61.pd

Solid and Cystic Tumor (SCT) of the Pancreas in an Adult Man

Solid and cystic tumor (SCT) of the pancreas predominantly Occurs in women, and the occurrence in men is extremely rare. We experienced a male case of SCT. A 38-year-old man was admitted with the complaint of upper abdominal pain. CT scan showed the presence of a mass in the head of the pancreas. The mass was composed of high density areas and low density areas. Ultrasonograms revealed the mass being composed of high echoic areas and low echoic areas. The mass .was hypovascular on angiography. SCT was suspected and pancreaticoduodenectomy was performed. The cut surface of the tumor showed mainly cystic degenerative areas containing dark red hemorrhagic materials. Microscopically, there were solid areas in the periphery and pseudopapillary areas in the center. No metastasis was found in the removed lymph nodes. The tumor cells were not stained by Grimelius' silver stain. The tumor cells were positive for alpha-l-antitrypsin (AAT) and neuron-specific enolase (NSE). Pancreatic hormones such as insulin, glucagon, and somatostatin were all negative. Electron micrograph showed that tumor cells were rich in mitochondria. Zymogen granules and neurosecretory granules were not detected. Estrogen receptor (ER) and progesterone receptor (PR) were both negative

A case of Autoimmune-related Pancreatitis - Usefulness of Fluorodeoxyglucose Positron Emission Tomography for the Evaluation of the Effect of Steroid Therapy -

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