Measured results for a new hole-pattern annular gas seal incorporating larger diameter holes, comparisons to results for a traditional hole-pattern seal and predictions /

Bibliographic Details
Main Author: Vannarsdall, Michael Lloyd
Other Authors: Childs, Dara W. (Thesis advisor)
Format: Thesis eBook
Language:English
Published: [College Station, Tex.] : [Texas A&M University], [2012]
Subjects:
Online Access:Link to OAK Trust copy

MARC

Tag First Indicator Second Indicator Subfields
LEADER 00000cam a2200000Ka 4500
001 in00002783511
005 20150922151205.0
006 m fo d
007 cr unu||||||||
008 121127s2012 txu obm 000 0 eng d
035 |a (OCoLC)ocn819423462 
035 |a (TxCM)http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-9759 
040 |a TXA  |c TXA  |d UtOrBLW 
049 |a TXAM 
099 |a 2011  |a Thesis  |a 1969.1/ETD-TAMU-2011-08-9759 
100 1 |a Vannarsdall, Michael Lloyd. 
245 1 0 |a Measured results for a new hole-pattern annular gas seal incorporating larger diameter holes, comparisons to results for a traditional hole-pattern seal and predictions /  |c by Michael Lloyd Vannarsdall. 
264 1 |a [College Station, Tex.] :  |b [Texas A&M University],  |c [2012] 
300 |a 1 online resource. 
336 |a text  |b txt  |2 rdacontent 
337 |a computer  |b c  |2 rdamedia 
338 |a online resource  |b cr  |2 rdacarrier 
500 |a "Major Subject: Mechanical Engineering" 
588 |a Description from author supplied metadata (automated record created 2012-10-22 13:24:58). 
502 |b Master of Science  |c Texas A&M University  |d 2011  |o http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-9759 
504 |a Includes bibliographical references. 
516 |a Text (Thesis) 
520 3 |a To reduce manufacturing cost and time, a hole-pattern seal incorporating holes of larger diameter (12.19 mm (0.48 inches)) has been proposed. Experimental leakage and rotordynamic coefficients for this new seal design are presented. This experimental data was compared to theoretical results generated by ISOTSEAL a program developed by Kleynhans and Childs. Finally, the performance of this new hole-pattern seal was compared to a hole-pattern seal tested by Wade. The experiments are configured to investigate the influence of changes in pressure ratio, preswirl, rotor speed, and clearances on seal characteristics. Due to stator stability issues, the peak inlet pressures had to be varied to allow for testing. Consequently, to study the effect of inlet preswirl and clearance, data were non-dimensionalized or normalized. Cross-coupled coefficients were relatively frequency-independent while direct coefficients were functions of excitation frequency. For all test cases, the seal developed negative direct stiffness at low frequencies. Tests showed that pressure ratio had minimal effect on rotordynamic coefficients. Non-dimensional cross-coupled stiffness increased with increasing preswirl causing the seal to become less stable with increasing preswirl. Cross coupled stiffness increased with increasing running speed. Two clearances: 0.1 mm (4 mils) and 0.2 mm (8 mils) were tested. The results demonstrated that non-dimensionalized stiffness is greater for the smaller clearance. The larger clearance develops larger normalized direct damping values, and has enhanced stability. Rotordynamic predictions are poor for cross-coupled coefficients. Generally, ISOTSEAL over-predicts direct stiffness and under-predicts direct damping. Negative stiffness was not predicted by ISOTSEAL. Predictions do improve for the smaller clearance. ISOTSEAL does a good job of predicting non-dimensional leakage. Non-dimensionalized direct and effective stiffness were greater for the "old" hole-pattern seal tested by Wade. However, the "new" seal generally developed greater normalized direct damping and exhibited a lower cross-over frequency. Non-dimensionalized leakage was greater for the seal tested here. Production of this new seal proved to be more difficult than originally thought. The price of the new seal cost approximately the same as an original hole-pattern seal. 
500 |a Electronic resource. 
650 4 |a Major Mechanical Engineering. 
653 |a Hole-pattern seal 
653 |a gas seal 
653 |a rotordynamic 
653 |a ISOTSEAL 
700 1 |a Childs, Dara W.,  |e thesis advisor. 
856 4 0 |u http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-9759  |z Link to OAK Trust copy  |t 0 
948 |a cataloged  |b h  |c 2012/11/27  |d c  |e ceaton  |f 1:45:40 pm 
994 |a C0  |b TXA 
999 |a MARS 
999 f f |s e4cbb181-810e-33d7-8541-bfe55ec55ac4  |i 218bed5c-cc34-385c-9788-005b2826d634  |t 0 
952 f f |a Texas A&M University  |b College Station  |c Electronic Resources  |d Available Online  |t 0  |e 2011 Thesis 1969.1/ETD-TAMU-2011-08-9759  |h Other scheme 
998 f f |a 2011 Thesis 1969.1/ETD-TAMU-2011-08-9759  |t 0  |l Available Online