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Kay Worda: Bladea, Veriable cross section, Shell*, Natural frequencies. Moda ahapes, Rit z method

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Kay Worda: 8lades, Compranor blade*, Cantrłfugsl oom-presaors, Vibration m aa sur amant, Talamatry, Holographlc tachniquaa, Interf ar o mat r te technique*

Biada vibratk>n maeaurement* wara carriad out on a high-praaaura, high mata-fk>w cantrifugal compretaor to datarmina tha excltatk>n machaniam. For tha axparimantal inve*ti<p-tion, aamiconductor atrain gag aa with a mułtichanneJ talamatry ayatam wara uaad. Tha m aa aur Ing pointa on tha bladea wara choaan uaing tha raautta of a atraaa calculation for tha yibrating blada by maana of tha FE-mathod. A raaaarch program was start ad wrth blada vi>ration maaauramanta in diffarant oparating rangaa of tha compranor and with two typa* of diffusara. Resulta ara praaanted for tha blada exci-tationa obtainad by throttłing tha comprassor at werioua rotational «>aada and for tha ca aa* of peasing raaonancaa by incraating tha rotational spaad at conatant throttla vałve posłtton.

84-1665

Dynamie Aniłyae of Practkal Bladea whh Shear Center Effect

V. Karadag

Tęchnical Univ. of Istanbul, Macka-Istanbul, Turkey, J. Sound Vib.. 52 (4), pp 471-490 (Feb 22. 1984) 8 figs, 11 tables, 32 refs

Key Worda: Bladea. Na tu rai frequencles. Moda ahapat, Finita element tachniqua

Shaar center effecta on tha natural fraquenciaa and modę shepea of rotating and nonrotating practical bladea are eon-a id er ad. An 18 dagraea of freedom thick beam finita element ia deyelopad. Banding and ahaer force diaplacemanta and alopea, and torałonai diapłacamanta ara taken aa dagraea of freedom at both anda of tha alamant. Total blada deflection alopea ara conskfered as composed of banding and shaar force deflection alopea In calculation* of blada atrain and kinetic energy. Thit element is compared with tha exi«ing thin and thick baam finita elements, and theoretical model*. Raault* obtainad for the vbration charactariatics of rotating and nonrotating nonuniform aarofoil croaa-tectioned bladea are compared wlth tha aveilabla calculated and experimantal vełues.

84-1666

YŁretioni of Bladea whh Yariahle Thickneaa and Camratnre by Shell Theory

J.K. Lee, A.W. Leissa.and AJ. Wang Ohio State Univ.. Columbus, OH 43210 J. Engrg. Gas Turbines Power, Trans. ASME. 106 (1). pp 11-16 (Jan 1984) 5 figs, 5 tables. 22 refs

A procedura for analyzing the vibretions of rotating turbo-machinery bladea haa been previouaiy deyaloped. This procedura is besed upon shatiow ahall theory, and utilizes the Rłtz method to datarmina frequencies and moda shepea. However, it haa been limited haretoforeto blada* of uniform thickneaa, uniform curvature, and/or twist and rectangular planform. The preaant work show* how the procedurę may ba generalized to eliminata the aforementioned reatrictions. Nonrectangular planform* are daeit with by a suitabla coordi-neta transformation.

BEARINGS

(Alao aee Nos. 1841,1843. 1844)

84-1667

A Study of EHD Lub raca bon in a Journal Bearing with Piezoriacoua Lubrkanta

S.C. Jain, R. Sinhasan. and D.V. Singh

Univ. of Roorkee, Roorkee, 247667, India, ASLE,

Trans. 27 (2). pp 168-176 (Apr 1984) 14 figs. 22 refs

Kay Worda: Bearinga, Journal baarings. Elastohydrodynemie propartiea

Tha deformation of a beering, which cen ba of the order of the fluid film thickneaa when the bearing operatea at larga eccentricłties, may affact tha performance appreciebly, and all the mora so łf the yiacosity of tha lubricant changas with pretsure. In thia peper, metchad aolutiona for praasura dittribution and tha beering diaplacement field, taking into account tha combined effecta of bearing liner deformation aa well aa change in yiacosity of tha lubricant, ara ob-tained by solving tha reapective govarning equations uaing a suitabla Keratkm echem# for eccentricHy ratios up to unity. The performance charactariatics of tha Journal bearing and thelr yeriatbns with bearing f!extoimV ara studiad with reference to acctntricKy ratio and a deformation coefficiem which ia a maaaura of the flexfeiłłty of bearing ahall.

84-1668

Modal An młyna ind Eiror Eatimates for Finite Journal Beariags

E. Hashisb and T.S. Sankar

SPAR Aerospace Ltd., Montreal, Quebec, Canada, J. Vib., Acoust.. Stress, Rei. Des., Trans. ASME, 155.(1), pp 100-106 (Jan 1984) 9 figs, 12 refs

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