1,281 research outputs found

    Experimental study of the flow field inside a whirling annular seal

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    The flow field inside a whirling annular seal was measured using a 3-D Laser Doppler Anemometer (LDA) system. The seal investigated has a clearance of 1.27 mm, a length of 37.3 mm, and is mounted on a drive shaft with a 50 percent eccentricity ratio. This results in the rotor whirling at the same speed as the shaft rotation (whirl ratio = 1.0). The seal is operated at Reynolds number of 12,000 and a Taylor number of 6,300 (3,600 rpm). The 3-D LDA system is equipped with a rotary encoding system which is used to produce phase averaged measurements of the entire mean velocity vector field and Reynolds stress tensor field from 0.13 mm upstream to 0.13 mm downstream of the seal. The mean velocity field reveals a highly three dimensional flow field with large radial velocities near the inlet of the seal as well as a recirculation zone on the rotor surface. The location of maximum mean axial velocity migrates from the pressure side of the rotor at the inlet to the suction side at turbulence kinetic energy. However, turbulence production and dissipation attain equilibrium fairly quickly with remaining relatively constant over the last half of the seal

    Turbulence measurements of high shear flow fields in a turbomachine seal configuration

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    The mean velocity and Reynolds stress tensor throughout a whirling annular seal are presented. The data was collected with a three dimensional laser Doppler velocimeter using phase averaging. Two axial flow conditions (Re = 12,000 and 24,000) were studied at one shaft speed (Ta = 6,600). The eccentricity and whirl ratios were 50 and 100 percent, respectively. There is a region of high axial momentum in this region is higher in the low Reynolds number case due to an axial recirculation zone that occurs on the suction side of the rotor at the inlet. The recirculation zone does not occur in the high Reynolds number case. At both Reynolds numbers, there is a recirculation zone on the rotor surface in the pressure side of the inlet. This recirculation zone extends from 20 to 200 degrees rotor zenith in the tangential direction, and is one third of a clearance wide radially. The high Reynolds number recirculation zone is 1.5 mean clearances long, while the low Reynolds number zone extends 2 mean clearances downstream. When compared to previous studies, it is apparent that the tangential momentum is no greater for a seal with whirl than for one without if other parameters are constant. Areas of high tangential momentum occur in the clearance where the axial momentum is low. Average exit plane tangential velocities in the high Reynolds number case are 1.5 times greater than those in the other flow case. These results are in general agreement with predictions made by other investigators

    An experimental technique for performing 3-D LDA measurements inside whirling annular seals

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    During the last several years, the Fluid Mechanics Division of the Turbomachinery Laboratory at Texas A&M University has developed a rather unique facility with the experimental capability for measuring the flow field inside journal bearings, labyrinth seals, and annular seals. The facility consists of a specially designed 3-D LDA system which is capable of measuring the instantaneous velocity vector within 0.2 mm of a wall while the laser beams are aligned almost perpendicular to the wall. This capability was required to measure the flow field inside journal bearings, labyrinth seals, and annular seals. A detailed description of this facility along with some representative results obtained for a whirling annular seal are presented

    Eccentricity effects upon the flow field inside a whirling annular seal

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    The flow field inside a whirling annular seal operating at a Reynolds number of 24,000 and a Taylor number of 6600 has been measured using a 3-D laser Doppler anemometer system. Two eccentricity ratios were considered, 0.10 and 0.50. The seal has a diameter of 164 mm, is 37.3 mm long, and has a clearance of 1.27 mm. The rotor was mounted eccentrically on the shaft such that the whirl ratio is 1.0 and the rotor follows a circular orbit. The mean axial velocity is not uniform around the circumference of the seal; near the inlet a region characterized by high velocity of the seal. By the exit, another region of high axial velocity is not uniform around the circumference of the seal; near the inlet a region characterized by high velocity of the seal. By the exit, another region of high axial velocity has developed, this time on the suction side of the seal. The magnitude and azimuthal distance of the migration increased with increasing whirl amplitude (eccentricity). Throughout the seal length, the azimuthal mean velocity varied inversely with the mean axial velocity. Increasing the whirl amplitude did not increase the magnitude of the azimuthal velocity at the seal exit

    Microwave Spectroscopy

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    Contains reports on nine research projects.Contract DA36-039-sc-7301

    Microwave Spectroscopy

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    Contains reports on seven research projects.United States Army Signal Corps (Contract DA36-039-sc-74895

    The Ursinus Weekly, April 28, 1941

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    Causes of cancer told to pre-meds by Pfahler • Manchester to sub for Wallace May 6 • Besse Howard will speak at forum Wednesday on topic, Spring, 1941 • Sub-frosh to view Ursinus this Saturday • May hop to feature music of Woody Leh • \u27Unity in diversity\u27 will be conference theme on May 7 • The Ursinus weekend travelogue around the circuit • Play \u27Lightnin\u27 centers around Calivada Hotel • Sixteen visit medical centers on excursion to New York • Five attend chemistry conference at Villanova • Powers of God are subject of vespers • Herber is pre-legal prexy • Meistersingers plan spring concert, May 1 • French Club to hear talk on prestige of French tongue • Debaters elect Lownes prexy; mixed team meets Drexel • Kriebel, Hartman to present reviews of Hilton and Brittain • Class of 1940 makes the grade in business and graduate work • IRC elects Byron president; discusses plans for next year • Local draft boards to weigh claims of students for deferment • Baseballers lose to Mules 3-2; trounce Dickinson 12-2 • Irvin paces track squad to victory over Delaware clan by 65-61 score • Netmen blank Lions in season opener • Co-ed net squad defeats Penn and Albright lassies • Zulick and Baberick win as Moravian beats golfers 3-2 • Freshman girls lead race in class softball league • Doc Baker heads old English game at Ursinus • Carter\u27s articles appear in historical dictionary • Hobos and bums to have poverty ball Saturday • Y officers to be inducted in service on Sundayhttps://digitalcommons.ursinus.edu/weekly/1816/thumbnail.jp
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