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l
, NaSA CR 137622
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" Acoustic Test Results_ _rom a36 Inch (0.91_t) Statozles8Lift Fs_, with Se._razed and
• Unserrated Rotor Blades
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D.L. St£mpert
,,._ .... .,,_,y• ,, prepared forT ,
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• ,_ IOkTXONALABI_OI_UTICSAND 8PACIIJ_I_NI_IIA'J['XO[[
i (NASA" CE-1376221 ACOUSTIC TSST RESULTS F_O_ t_75-182_2:'_' A 36 INCH (0.91,m) STATORLESS LIFT FAN WITH- SERRATED AND UNSERRATED ROTOR BLADNS
(Generax Electric Co.) 51 p HC $_.25 Unclas.
', CSCL 20A G3/07 13603
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1. _m_N_ 2. GMmm_ _ No. 3. Re_s Cm_ No.
u_A (:1 137622
Acoustic Test Results fro" • 36 inch (0,914 n) Sr_torleu Lift Januar 7 1975Fan with Serrated end Unserratsd _otot Blades & Performins Oq_izsti_ Code
'7. _mo_ _ & Pe_xm_S_ _ N°"
D.L. St 1rupert R7_LKCA06• _10.Work Unit No.
_u_ Omm_m Neme_d k_m ....
Goner al Klactz_Lc CollpaX_7 II. Contractor Gnmt No.
- ktreraJ[t EnlrLne Group NAS2-5462CincinnatL, Ohio 45215
13. TYlm of Reportand Period(3ovunJd
1_. Sl_in0 ASuw/Nemo end kJdmn Coutrsctor Report
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Tests of the L1r336/E star )floss lift fan vJLth serrated sad unserratsd rotor ludinsedae8 indicated broa4bad noise reductions of 2 to $ dZ in Lhe forvlrd quadrmt.
' Broadband noise levels near the blade paesin8 froquanc7 end above were reduced •sly!
from 80 to 100 dear•on re18ULve to the inlet.
17. Key Wo_ (_:,_ by A_J_x(_) I& oi_iuut_ Swtmontt
IJ'336/K
Acoustics UnclaseLfled - un14-4tedSt•torless lift f_n_ft fanSerrsted rotor blsdss
ROtOr-ILl,One no lee
10. SecurityCImlf. (of thisrm_ 20. SecurityGrail. lot thispe_l :_1.NO.of Peps 22. Wtce"
UnclaaeLf4 od OnelaaslfLed 65
"For salebytheNationalTechnicalInfo_mtionService,SlxinifieM,Virlinia22151
1975010170-002
TABLE OF CONTENTS
_ Section P___
List of Tables
List of Figures
- I Smeary 1
II Introduction 2
III Test Hardware 3
r_ A" LF336/E Statorless Fan 3
i B. J85-5 Gas Generator 3
IV Test Site 4
V Sound Data Acquisition and Processin8 5
A. Data Acquisition 5
B. Data Processing 5
1. 1/3 Octave Bands 5
2. 20 ltz Narrowbands 6
VI Results and Comparisons 7
A. Serrated to Unserrated Statorless Lift Fan 8
B. Serrated Fan with and without Circular IGV 8
C. Serrated and Unsezrated Statorless Fan with Circular IGV 8
VII Conclusions 10
, VIII Nomenclature 11
i IX References 12
ill
1975010170-003
T 1 ! ] v, i !
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LIST OF TABLES
Number
I LF3361E Acoustic Test Swmary 13!
II LF336/E Llft Fan Desi_ Parameters 14I
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1975010170-004
J• _ I I i
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LIST OF FI_JRES
I. Photograph of the LF336/E Statorless Lift Fan. 15
2. Cross Section of the LF336/E Statorless Fan. 16
3. Summary of Serratlon Geometry. 17
4. Photosraph of the Circular ICV Installed on the LF336/E. 18s
S. Aerial Photograph of NASAAmes Outdoor Test Site. 19
6. Microphone Orientation for the Unserrated LF336/E AcousticTests. 20
7. _icrophone Orientation for the Serrated LF336/E Acoustic Tests. 21
8. Acoustic Data Acquisition at NASAAmes Outdoor Site. 22
9. Serrated and Unserrated L_336/E PNL Directivity Patterns. 23
I0. Serrated and Unserrated LF336/E I_L Spectra. 24
11. Serrated and Unserrated L¥336/E 160 Hz 1/3 Octave Band SPLDtrectivity Patterns. 25
12. Serrated and Unserrated LF336/E 1600 Hz 1/3 Octave Band SPLDirectivity Patterns. 26
13. Serrated and Unserrated LF336/E 2500 Hz i/3 Octave Band SPLDirectivity Patterns. 27
14. Serrated and Unserrated LF336/E BPF 1/3 Octave Band SPLDirectivity Patterns. 28
15. Serrated and Unserrated LF336/E BPF (1/3 Octave Band end 20 HzNarrowband) SPL Directivity Patterns on a 150 foot (45.7 m) Arc. 29
• 16. Serrated and Unserrated LF336/E 20 Hz Narrowband Spectra at 60Desrees. 30
: 17. Serrated and Unserrated LF336/E 8000 Hz 1/3 Octave Band SPLDirectivity Patterns. 31
18. Serrated LF336/E PNL Directlvity Patterns With and Without
i a Circular ICV. 32
19. Serrated LF336/E PNL_s With and Without Circular ICY 8s ai Function of Fan Speed. 33
V
I
1975010170-005
LIST OF FIGURES (Concluded)
20. Serrated LF336/E BPF SPL (I/3 Octave Band) Directiv!ty PatternsWith and Without Circular ICV. 34
21. Serrated LF336/E BPF (20 _z Narrowband) Directlvity PatternsWith and Without Circular ICV. 35
22. Serrated LF336/E Narrowband Spectra at 50 Degrees With andWithout Circular ICV. 36
23. Serrated and Uuserrated LF336/E PNL Directiv!ty Patterns WithCircular ICY. 37
24. Serrated and Unserrated LF336/E PNL's With Circular ICV's
Compared as a Function of Fan Speed. 38
25. Serrated and Unserrated LF336/E PWL Spectra With Circular ICV. 39
26. Serrated and Uneerrated L¥336/E BPF 1/3 Octave Band SPL
Directivity Patterns With Circular IGV. 40
27. Serrated and Uneerrated LF336/E Narrowband Spectra With CircularIGV. 41
28. Serrated and Unserrated LF336/E With Circular IGV 160 Hz 1/3
Octave Band SPL Directivity Patterns. 42
29. Serrated and Unserrated LF336/E With Circular IGV 1600 Hz 1/3
Octave Band SPL Directivity Patterns. 43
30. Serrated and Unserrated LF336/E With Circular IGV 2500 Hz 1/3
Octave Band SPL Directivity Patterns. 44
31. Serrated and Unserrated LF336/E With Circular IGV 8000 Rz 1/3
Octave Band SPL D4rectXvity Patterns. 45
i vi
1975010170-006
SECTION I
$U)RARY
The LF336/E statorless lift fan system was designed and tested with twosets of fan blades - one with serrated rotor leading edges and one with un-serrated r_tor leading edges.
Fan broadband noise reductions froa 2 to 5 dB were achieved in the forwardquadrant at frequencies from 100 to 2500 Hz. Broadband noise near and abovethe BPF was reduced only at angles of 80 to 100 degrees. BPF reductions werenot achieved with serrations.
1
1975010170-007
SECTION II
INTRODUCTION
The LF336/E statorless lift fan system was designed, fabricated, andtested under Contract NAS2-5462 which was sponsored by NASA Ames ResearchCenter. Included in this progrsmwere two sets of fan blades - one withserrated rotor leading edges and one with unserrated rotor leading edges.Acoustic test results on the unserrated LF336/Ewere reported in Reference I.
Serration geometry for the LF336/E statorless llft fan was selected basedupon cascade tests of serrated leading edge bladlng at high subsonic speeds asreported In Reference 2.
it This report compares the serrated and unserrated LF336/E statorless liftt
1 fan results from tests conducted at NASAAmes Research Center. Table I smma-rizes the test configurations and speed points investigated which are pertinentto this report.
2
1975010170-008
t ! 7 ' _ T
SECTION III
TEST BARDUARE
The basic test propulsion system consisted of the LF336/E statorless fan,
the J85-5 engine, and interconnecting ducting as shown in Figure i. Thesystemwas installed in a test stand which provided for mounting the fan and enginesystem with the fan inlet oriented in a vertical plane. The fan inlet bellmouthwas installed flush with a flat plane surface which simulated a wing upper sur-
: face of a fan-in-wing installation.
A. LF336/E Fan System
The LF336/E fan is a single stage statorless turbotlp llft fan which is
designed to operate without either inlet guide vanes or exit stator rows. The
fan has a 36 inch (91.44 cm) diameter and incorporates 42 blades in a tip tur-
bine driven, single stage rotor. The single stage rotor develops a fan pressureratio of 1.25 at a fan design tip speed of 1060 feet per second (323 m persecond). The design pressure ratio of 1.25 assumes no recovery of the exitswirl component. Accordingly, the overall total-to-total pressure ratio is1.32 at design operating conditions.
A sketch of the fan is shown in Figure 2. Selected design par_eters arepresented in Table If. When the fan was tested, it was modified by the instal-
lation of tip turbine exit stators.
Serrated fan blade geometry for this test is presented in Figure 3. Cas-cade tests (Reference 2) had concluded that the best aerodynQic and acoustic
performance was achieved with serrations that had a height greater than sixpercent of the blade chord and a helght-to-spaclng (H/S) ratio of 1.5 or less.
Both the serrated and unserrated statorless fans were tested with a clr-
cular inlet guide vane. This IGV is shown installed on the serrated statorlessfan in Figure 4 and would be used to improve aerodynamic performance in cross-flow. IGV-to-rotor spacing was approximately 0.25 inches (0.63 cm) or about0.06 true IGV chords,
B. J85-5 Gas Generator
The fan tip turbine was driven by a J85-5 engine modified to a convention-
al turbojet engine configuration. The gas gene:ator is shown in Figure 1
coupled to the llft fan. Also evident in this photograph is the acoustic sup-
pressor which was installed on the J85-5 inlet to suppress gas generator inletradiated noise. The engine exhaust is direct-coupled to the fan scroll inletthrough a transition duct.
3
1975010170-009
I
SECTION IV
NASA AMES RESEARCH CENTER OUTDOOR TEST SITE
LF336/E statorless Lift fan testing was conducted at an outdoor test sitelocated at NASA Ames Research Center. An aerial view of the test site is
presented in Figure 5. As the photograph shows, the acoustic path to anygiven microphone was in some places asphalt and concrete, and in others shortgrass and asphalt. The microphone layout for the unserrated test is given in
Figure 6 and the serrated test in Figure 7. Far field microphones were on a150-foot (45.7 m) arc in ten degree increments from 0 to 160 degrees relativeto the fan inlet. For both tests Runs 1 and 2 had the near field microphoneson a 20-fomt (6.1 m) arc located in 20 degree increments from 30 to 15_ :._=res.All successive runs had the seven 20 foot (6.1 m) arc microphones locat=_ dt90, 110, 130, 150, 210, 230 and 250 degrees. This latter arrangement dupli-cated the near field microphone layout used when the unserrated statorless fanwas tested in the NASA Ames 40' by 80' (12.2 m x 24.4 m) wind tunnel.
!
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1975010170-010
SECTION V
SOUND DATA ACQUISITION AND PROCESSINC
A. Data Ac_uisitlon
All data acquisition for the war and far sound fields was made usingBruel-KJaer model 4133 microphone systems in conjunction with a Honeywell Model
7600 tape recorder operated at thirty inches per second (76 centimeters per
second). Figure 8 includes a schematic of the data acquisition system and
photographs of the equipment and the General Electric Mobile Sound EvaluationUnit.
All far field microphones were oriented to point at the test vehicle andhad Bruel-KJaer UA0237 windscreens installed on the microphone heads. Thenear field microphones were oriented to point in the same direction a_s theJ85 inlet and used Bruel-KJaer model UAO052 nose cones.
The f_'ee field frequency response of each microphone head is derived from ,
a pressure response curve recorded automatically by the electro-statlc actu-ator method traceable to the Bureau of Standards. The free field characteris-
tics for various angles of incidence for microphones with protecting grid, nosecones, and windscreens are given by the microphone manufacturer. Individualmicrophone head sensitivities are determined by the insertion of a Bruel-KJasrpistonphone on the cartridge mounted to a standard microphone system. Boththe pistonphone and standard microphone system are traceable to the Bureau ofStandards.
Prior to initiation of testing, a frequency response of each data channel(minus microphone head) was made by the insertion of a Hewlett-Packard Pseudo-Random Pink Noise Generator into each cathode follower and recorded on magnetic
tape.
Prior to and subsequent to each day's testing, an absolute calibration wasmade by the insertion of a pistonphone on each microphone and recorded on tape.Any microphone whose voltage output with the pistonphone applied was found todeviate more than + 1.5 dB from the laboratory calibration was replaced.
During test operations, sound wes recorded continuously for a minimum oftwo minutes to allow enough sample length _or data processing. All acousticdata was taken at wind speeds below 5 mph (8 km/hour).
B. Data Processing
1. 1/3 Octave Bands !
All 1/3 octave band data processing was performed at the General ElectricEdwards Flight Test Center facilities using a General Radio real time analyzerin conjunction with a Honeywell 316 and SDS930 computer. Thirty-two second
] 9750] O]70-0] ]
i [ 1 ' t lI 1
i I
averaging time was used for data processing with data for each angle sampledfrom the same period of time for each data point.
Before data processing could _e initiated, the total data acquisition and ;reduction system frequency response characteristics had to be determined andmade available in the computer for final data processing. The first step inthis process was to analyze the Pink Noise calibration tapes for each datachannel, and determine the response characteristics for the total system asreferenced to 250 Hz (frequency of the pistonphone) at each 1/3 octave band.Final one-third octave data processing was made by determining absolute soundpressure levels, for the 150 foot (45.7 m) arc and 200, 500 foot (61 m, 151 m)sidelines, corrected to standard day (59 ° F (15 o C), 70% relative humidity)conditions as per Reference 3 and for ground attenuation effects as per
_ Reference 4. /
2. 20 Hz Narrowbands
All narrowband analysis was made at the General Electric Edwards FlightTest Center facilities using a Federal Scientific Ubiquitous Spectrum Analyzerand a 139B Digital Averager. All data was processed using a 20 Hz bandwidthfilter and an averaging time of 12.8 seconds. No corrections for humidity oracquisition/processing responses were included in the narrowband plots.
/
6
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1975010170-012
! I 1 ! ,
SECTION VI
RESULTS AND COMPARISONS
A. Serrated to Unserrated Statorless Lift Fan
Serrat[ons reduced the perceived noise level (PNL) by 2 to 4 PNdB orimar-ily from 80 to i00 degrees (relative to the fan inlet on a 200 foot (61 m)
sideline as shown in Figure 9 at 6000, 5300, and 4800 rpm. At forward angles,however, the use of PNL is somewhat deceiving since it weights the 1/3 octave
• band which contains the BPF most heavily and in the forward angles the BPF notfan broadband noise controls the spectra. Figure I0 presents a comparison ofserrated and unserrated sound power levels (re 10 -13 watts) at three fan speeds.Serratlons clearly reduced fs_ broadbpnd power levels from 630 Hz to the BPFby I to 2 dB. Above the band containing the BPF, there was little or no reduc-tion due to serratlons. The region of the spectrum around 315 Hz is influencedby the ground null; however, lower frequencies down to i00 Hz show lower soundpower levels with the serrated rotor. There are two possible reasons for thereduction at these low frequencies. One is that the fan is performing differ-ently with the serrated rotor and Jet velocities are reduced thus loweringthese low frequency levels. A second possibility is that these low frequencieswhich are usually associated with Jet noise are in fact fan broadband noisewhich has been redaced by serratlons. Figure Ii indicates that the second
possibility is correct. Here the serrated and unserrated 160 Hz sound pressurelevei_ (SPL's) at three fan speeds are compared at acoustic angles on a 200foot (61 m) sideline. The SPL's from 30 to i00 degrees have been reduced byserratlons by 2 to 5 dB. However, aft angles show llrtle change with serra-tlons as one would expe=t if these angles are controlled by Jet noise not fanbroadband noise. Similar results are available for 100 and 125 Hz SPL's.
At higher fan broadband levels, e.g., at 1600 Hz in Figure 12, the effectof serrations can be seen at angles of 30 degrees rearward at 4800, 5300, and6000 rpm. For some reason, which is not clear at this time, the 110 degreelevel was not reduced by serrattons. The reductions range from 2 to 4 dB.Similar results are observed for the 2500 Hz SPL's in Figure 13. Again the110 degree SPL's with serrations are the same as the unserrated levels.
Serrated and unserrated SPL's of the 1/3 octave bands which contain theBPF for 6000, 5300, and 4800 rpm are compared in Figure 14. At forward anglesup to 80 degrees the SPL's at the two lower fan speeds show no effect due toserrations and the 6000 rpm SPL's only show about a 1 dB drop due to serrations.The forward SPL's which contain the BPF are controlled by the BPF and the BPFis not affected by serrations or are slightly increased as the narrowband SPL'sin Figure 15 indicate. Note that Figure 15 compares both 1/3 octave band BPFand 20 Hz narrowbsnd BPF on a 150 foot (45.7 m) arc. Typical 120 Hz narrowbandspectra are shown ,n Figure 16 fo= 60 degrees and 120 degrees. The aft spectraBPF is only 4 dB above the broadband noise which accounts for the differencebetween the aft quadrant 1/3 octave band BPF &_J 20 Hz BL,F levels in Figure 15.
7
1975010170-013
At frequencies above the KPF, serratfons do not achieve a reduction exceptat 80, 90, and 100 degrees. Figure 17 ls a typical frequency, 8000 Hz, at threefan speeds.
B. Serrated Fan with and without Clrcular IGV
Te_ts on the LF336/E statorlees llft fan both serrated and unserrated
included configurations _rlth and without a eircul at inlet guide vane. As shownin Figure 4, the inlet guide vane is a 180 degree turnin- vane positioned nearthe fan inlet bellmouth and i8 located less than 0.1 rotor chords forward of
the rotor leading edge. This device is intended to improve fan performance incrossflov with little change at static fan operation. •
" Installation of the circular IGV affected an increase in perceived noiselevel 68 shown in Figure 18 at 6000 and 5300 rpm. Figure 19 indicates that at40 and 50 ds_rees there is no difference attributable to the circular ICV atlow speeds. At 60 and 70 degrees the configuration with the circular ICV is1 to 2 _ higher over the entire speed regina.
Installation of the circular ICV also in_reaged the 1/3 octave b_nd which
contains the BPF, This is shown in Figure 20 at 6000 and 5300 rpa. 20 Hznarrowband directtvity on a 150 foot (45.7 m) arc is shown in Figure 21 andindicates a change in the forward quadrant BFF with circular ICV. Figure 22compares 20 Hz natrogband spectra at 50 degrees and 60 degrees and shows thatthe circular ICV affects only the BPF and not fan broadband noise. Sin/larresults were observed when the circular IGV was installed on the tmserratedrotor (Reference 1).
C. Serrated and Unserrated Fan with Circular IGV
With the circular ICV installed, the serrated rotor reduced the forwardquadrant I_L'8 at 6000 rpm by 4 PHdB at 60 and 70 degrees as shown in Figure23. At 5300 rpa the reduction due to serrations was I to 4 PNdB from 30 to100 degrees. As indicated by Figure 24, these forward quadrant Ph'L reductionswith the IGV installed are generally 2 to 3 PHdB down tc 3000 rpm where theeffects are minimal.
Sound power level (re 10 -13 watts) reductions were achieved with the ser-rated rotor 88 evidenced by Figure 25. Fan broadband ISL'a froa 500 to theBPF and above the BPF are reduced 1 to 3 dB. For this configuration the 1/3 _octave band which contains the BPF shows a 2.5 dB reduction. When rotateda8 a function of acoustic angle, the 1/3 octave BPF band shows as such as 5
dB reduction in SPL with serration8 at forward masle8 while the aft angles8how slight reductions. This is shown in FiSure 26 at two fan speeds. Typl-
cal forward and aft narrowhand colparisons at 6000 tpm are shmm in ,Figure 27.Note that the serrated rotor with the circular ICV installad has reduced not
only the fan broadband noise but also the BPF and its harnonics. This is incontrast to the case without the IGV where serration8 had no effect on she BFF.
1
8
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1975010170-014
I i I ,' ! i
-ILow frequency fan broadband SPL's are decreased by the serrated rotor by
2 to 3 dB in the forward quadrant as shown in Figure 28. In the aft quadrant,Jet noise is dominant and no serration effect is vlslble. Similar results atthese low fzequencles were observed for the fan without the IGV and furtherconfirms that fan broadband noise is present and that serratlons reduce thisfan broadband noise. Figures 29 and 30 present fan broadband SPL's at 1600and 2500 Hz below the BPF. Serratlon reductions of 2 to 5 dB are present overthe entire sideline. Reduction is also evident above the BFF an shown in Figure3).; however, the angles reduced are from 30 to 120 degrees.
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1975010170-015
SECTION VII
CONCLUSIONS
The 1/3-octave band SPL's from 100 Hz to 2500 Hz (excluding bands influ-enced by the sround null) show reductions due to serrations of 2 to 5 dB inthe forward quadrant. Bands close to and above the BFF shc_ reduction due toserrations only at angles of 80 to 100 degrees.
BPF reductions were not achieved with eetraticeas. The reduction in broad-
band noise and not tones is consistent with rotor alone analyses and cescadstests which indicated that serrations primarily effect fluctuating pressureon the rotor and thus broadband noise generation.
Installation of a circular IGV resulted in 8 1 to 2 PNdB increase at for-
ward ankles. This circular ICV increases the BPF ac forward angles from 3 to7 dB.
10|
'i
1975010170-016
SECTION VIII
NOMENCLATURE
SymbolorAbbrevlation Deflnit ion Unit s
BPF Blade Passing Frequency Hz
C Blade Chord inches (an) _,
f Frequency Hz
H Serratlon height inches (cm)
IGV Inlet guide vane ---
.: L Peak-to-Peak Spacing of Serratlons inches (cm)
OGV Outlet guide vane ---
PNL Perceived Noise Level PNdB
PWL Sound Power Level, re 10-13 watts dB
R Radius inches (cm)
S Serration Spacing inches (cm)
SPL Sound pressure level dBre: 0.0002 dynes/cm 2
II
1975010170-017
SECTION IX
REFERENC|_
: I. Stimpert, D.L. ; "Acoustic Results from Tests of a 36-1nch (0.914 m)Diameter Statorless Lift Fan", General Electrlc Company TechnicalInformation Series R73AEG360, June 1974, NASA CR137621.
2. Smith, E.G.; and Sowers, H.D.; "Cascade Teats of Serrated Leading EdgeBlading at High Subsonic Speeds", General Electric Company TechnicalInformation Series R74AEG283, December 1974, NASA CR2472.
3. Standard Values of Atmospheric Absorption as a Function of Temperatureand Humidity for Use in Evaluating Aircraft Flyover Noise. S.A.E. ARP866,August 31, 1964.
4. Hethod of Calculating the Attenuation of Aircraft Ground to Ground NoisePropagation During Takeoff and Landing. Aerospace Information Report 923,Society of Automotive Engineers, Inc., August 15, 1966.
12
1975010170-018
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!j,
1975010170-019
Table 11. LF336/E Lift Fan Design Parameters.
Kechanical
Design point Limit Speed
Fan pressure ratio 1.25 1.196
Fan £Iow, Ibm/see (kg/sec) 172 (78) 132 (69.4)
Fan tlp speed, ft/sec (m/set) 1060 (323) 950 (290)
Fan apeed, rim 6748 6048
Blade number 42
Fan tip diameter, inches (ca) 36 (91.44)
Radius ratio (rotor Inlet) 0.554
4
1 141
i'
1975010170-020
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16
1975010170-022
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1.8_6In.(_.688era.)
H - .116 in. (.295 cm.)
./c - .o63s - .¢76in.(.193c,.)L - .193in. (._90cm.)
R - .o61in. (.155era.)
,is- 1.5L/H- 1.66
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I,I(K_I3. 8UIlI_ Or SEm_ATIGIIGEOMEI'_ •*
17
1975010170-023
18
1975010170-024
, !
19
1975010170-025
, ! .... i ..... I-...............................I..............."_ .........................."l......................._............
20
1975010170-026
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BRUIIL- I_AIDI26_.5 CATHODEFO_r_
FIGURE 8 ACOUSTIC DATA ACQUISITION AT NASA AMES OUTDOOR SITE
22
1975010170-028
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23
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1975010170-029
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24I
1975010170-030
f I !1 I ! !
• I
tOO iZQOFT SII_.LINE I..F_J6/F.STRT01M.ES_5FRNT[ST __--I61 H SIDELINE TESTSITE--Nf_FI RIf..S _ ,om_,_, _,w,[
_T_ 160 H_ 1/3 a.o. ---aenimmp_ ]
90_ WOOnra J
'f
_ ' e; ' ' ' '0 _ 80 t00 t20 tq,0 160
it•_ !00' 2QQFT SIOELINE LIF_I_E IJTRTOflI_SSF_N TEST61 H S|Q(L|NE TESTSITE--NRSRRHES _Cmlsmermmmn160 HE !/S O.O. .--_mmnmm_n5300 nr_
,,,90
..J
- J-|m60
_ , , ,.... . , .0 20 q,O 60 90 tO0 120 lqLO 160
llO.200 fT SIDELINE LFSqJ6/ESTFITOflLE_PJF_I4TEST _ uiaamulmPo_5! H SlOE[LINE TESTSJTE--NRSRRI4ES160 HZ I/30.fl. ---amnmonmn6000 FIPH
mlO0"
_1
........................\o 2o _o _o- _o, 1oo 1_o lio 1so *
_, FXGUKE 1, SEP,I_,TED AND UHS_.RBATED LF336/E 160 Hz 1/3 OCTAVE B/LMDSPL _)XP,ECTIVXTY PATTERNS
25
' i
1975010170-031
I00,200 FT $ll)F.L|NE LF335/E 5TIITORLE$5FI_i TE_,T61 1451DF.LINE TEST$1TE--NR_qIWqlE_ _ullsEmlw_mm_1600 ItZ !13 O.O. --_ semim_qlO00Rr_
g.
I.
0 20 _ 60 _ i_' 120 lqO 160
FT $10Et,.INE _ 5TR_35 FANTEST _veamw'eommel61. It '_IOF..LINE TE$1"$1"Tf.--tNRSRRUES1600 HZ i/3 0.8. --- ammm_5.aO0RPI,I
8 _
t.
soo so _o so eo Lso Lq,o t,so
!"00' _0 FT $tDEI.]N_ LP'_J6/IE$TRTORLJESSr_N TE$1' _ uiimimlo,nmMa6L H _IDELIN[ TE'STSITE- _ RH[$1600 I_ I/3 0.11. --- snmmmm6000 nln,i
.3
g®
i I I i 4 1 '50 _(_ 60 80 tOO I,_ L_ !,60RCOLmTI('RNGL[. 0(-61_$
FIGURE12 SERIUtTEDAND UNSEF3.4TEDLF3361E 1500 iiZ 113 OCTAVEBANDSPL DIP.ECTIVITYPATTERNS
• 26
%,
1975010170-032
* f i '_
tO0200 FT 510[LINE LP33S/E51"RT01_.(55FRNTF.$T61 H $IOELIME TEST$1TE--NR_q_ _umJmmrmmmm2500 HZ 113 0.8. -.. _mmntommt_O0 RPI,t
9O
•_J
IIn
20 80 100 120 I 0 160
100,200 FT $10F..LINE LF336/(- STRTOI_.E55FRNTEST
_) 51OF..LINE T_ST 51TE_ RI_$ _uunmrmnmlt_ I/30.O. --.smmmmmS300 re'V1
m_
_ " .6 . , . ,0 qO 80 I,O0 I,_ t,qO
It'J) L2tO0FT $1I)(LINE LF_J6/E $TRTORLE$$FANTEST
_:_ $10EI.IM( TESTSrTE--NR_IqRNE$ _ ummtm_omrmi _ IIS 0.8. ---mesm6000 I_
!
1
II I 4, JIl I , O I '
0 30 qo 6"0 00 1,00 t,_lO l,tiO I_0_aUllYlC RNGt.E.OC-mEE8
FIGURZ 13 SERRATED AND UMSEiUIATED LF3361E 2500 Rz 113 OCTAVE BANDSPL SIRECTIVITY PATTERNS
27
1975010170-033
!10,200 FT SII3ELII_ LF3":J6/E5TRTOI_.ES5FRNI'E5T61 M SIOELINr TESTSITE--NR_I RI'IES _ u_r_u_.onotre3150 HE_ lONE --- _w_ nolanqSO0fll_
.3
g,o
m.
_ - , , , ,._ . ,0 20 _ 60 80 1130 120 lqO 160
110FT SII]F.LINE LF336/E STRTOP4.ESSFANTEST
t_}O_SIOELINE TESTSITE---NRSRI:I'ES -- ummnmgnmgqHEPUFIETON[ --- tmN_o nmm5500 FIP_
tO0
-J
! * I e i 4 q0 20 qO 8] BO I00 120 lqO 160
110"200 FT SIOELINE LF_I6/E STRTOFILES5F_ TEST _ ummumonmm
t_ SIOELIIqE TEST$1TE--:NRSRP_5I_ PUI_ TONE -- - gmnwnmn
_lO0._1
g,o
._ /"'w
Crl ....
RCOUSTICRNGI.E,IZGI_S
F'IGU' It, SERIIATEDAND I.JNS_R.qATEDLF3361E BPF 113 OCTAVKBANDSPL DII_CTIVITY PATTKP,NS
28
l _," i
1975010170-034
150 FT. ARC LF_36/E STATORLESS FAN TEST ----UNSERKATED ROTOR45.7 M. ARC TEST SI_E--NASA AMES ----- SERRATED ROTOR20 HZ BANDWIDTH6000
60 ° ACOUSTIC ANGLE
I
8O
7O
600 1 2 3 4 5 6 7 8 9 10
FREQUENCY. _tz
120 ° ACOUSTIC ANGLE
,_
i '°,_ 0 1 2 3 4 5 6 7 8 9 10
FREQUENCY, KRz
FIGURE t6 SERRATED AND UNSERRATEDLF336/E 20 Hz NARROWBANDSPECTRAAT 60 DEGREES
3O
1975010170-036
' ] 1 ' !I ' I
I i
II 6| H Lmsemmto_ID•I B000 S][](LIN[ I'['H';][f--Nl_'.Nq/I_SHl I/'_ [1.U. "*mRrzum_m
I ,u9°¢-s
0,.
500 20 q0 60 80 I00 120 I_0 160
I 2100 3]0ELJME LF3361E STRTORLESSFRN TEST
m0FT
: 6LN 3[DILXNE TEST SITE_ItqSR RRE3 _umalnmmtm8000 H_ 113 O.8. --- sI_m_.mmm
t 8s° s.soo_..
l
0 20 qO 60 80 L00 120 I,q,O 160
il.0.a00 FT SlOl.r-,ClmII_LF338/E STRT_M.ESS FRN TEST61 II 3[O[LIN_ TEST SJ'TE--4q_l_q,41_5 --um_mmrEomrl8000 HZ"I/3 0.I. --- smmr_oI_8000 _M
a
i.
gO0 ao qO so c,. too ,_o _o 160_TIC _NC4.E.0E_EE$
FZGUIU_ 17 SERI_ATgDAND UNSERRATEDLF336/E 8000 llz I/3 OCTAVE BANDSPL DIRECTIVITY PATTKRNS
31 _
_9750_0_70-037
t30I'_O FT SJOELINiE LF336/E STRTORL.ESSF/IN TEST 141I'I_T
-- Cl/ICIX_ I_
61, H SIDEL|NE TESTSITE-NASRFII_ES ran+--- csmu_ joy !SEP,I_TED ROTOR
I.. 1
ItO t/
i,® !
90 '
oo ..,.. , , ;, , ' '0 .:u qO 60 8,, tO0 120 l_O 160', ACOUSTICRNG4,.F,DEGHEES
130FT SIOELJNE LF33B/ESTRTORLESSFRNrEST --_J_ Jw
6I M SIOELINE TESTSJTE-NF_qI:_E$ i.Sm_tEOROTOR ---_1_ ,o,, _,,
6000PIPit _-
_ 120 .-o_ ,"%1s _+
I000
l;; 0 20 _ 60 eo too 12o • t_o t6o, ACOUSTICANGLE,OEOIIEES
FIGURE 18 SERRATgDLF336/E PNL DIRECT[VITY PAI'_P,NS b'ITH AND tiWITBOUTA CIRCIJIJi£ IGV
32". |
'L
1975010170-038
• I ]
: i
110 200 FT $]OELINE LF336/E 5TATOFILES$FANTEST _.in_euTCll_Ut,m l_t61 R SlOELINE TEST$[TE-t_ISARIf.S .ix.¼000HZ 6PF SERRATEOROTOR ""¢JnCULMZ_53O0RPM
IO0
0
70 ;/°
/
60 _ ' ' ' ' ' ' '0 20 qO 60 BO tOO 120 IU.O 160
ACOUSTICANGLE.OEGREES
rIO200 FT SlDELII_ LF336/E STATOPILESSFNI TEST _II_L_61 H SlO_LINE TESTSITE-NASAl_S .zn,_000 HZ OPF SERIVITEDROTOR "'" cmmJaIW800O RPM
IO0,
0 20 YO 80 80 lo0 120 IqO 160RCOUSTICANG.E, OEGeIEr.S
_m FIGURE20 S]_RATED LF33b/E BPF SPL (1/3 OCTAVEB,aJ_D)DIP,,lZCTIVITY-j, PATI'ZI_S WITll _ WITHOUTCIRCUIJ,R IGV
34
,, !
1975010170-040
Jl_ ............. n Ill ni II ........... natalni Ill ...... .................... .......................... -- .......................... _g_ ..... _ .........
............... :!.......... L...... 1.......... .....] ! 4t I
150 FT. ARC L]_36/E STATOlU_SS FAN TEST WITHOUT45.7 M. ARC TEST SITE---NASA AMES CIRCULAR IGV20 Hz BAND_DTH SERRATED ROTOR WITH6000 RJLRI CIRCULAR IGV
50 ° ACOUSTIC ANGLE110 I.,
m 1 vo
600 1 2 3 4 5 6 7 8 9 10
FREQUENCYt Kliz
60 ° ACOUSTIC ANGLE ,
100
90
: 80
7O
0 1 2 3 4 5 6 7 8 9 10
FltlQUENCY_ KIIz
FIGURE 22 SERRATED LF336/E NARRO_3AND SPECTRA AT 50 DEGREES WITH
AND WITHOUT CIRCULAR ICY
35
_- J- i"
1975010170-042
130 ]'200 FT SIDELINE LF_I6/1E$TRT081.ES5FRNTEST
61 H SIDELINE TESTSITE--.NI:ltSRRHES --tmmm_ mintCIRCUL._IGV --- smm_omint
i_,110'
gO l i i o 8 t ' l,
0 20 qO 80 8O 100 120 lqO 160I:ICOUSTICRNGLE.DEGREES
i 130 12QOFT SIDELINE I..F_JI6/ESTRTORI.ESSFFIFtTESTi 161H SIDELINE TESTSITE--NRSRRIDES --_mm
CIRCULRRIIW ---smmme mm
_ L
.3-' _110,
.,./
ZOO.
.
o _ ,L 6o ,oo _ 1o _6oRCOUSTICRNGLE.DEGqEES
FIGURE 23 SERRATED AND UNSERItq'£EDLF336/E PNL DIRECTTVITY PATTERNSWITH CIRCULARIGW
37
,l
1975010170-043
' T I 1 1 T ! ,/
i , 1
170[200 FT $IOEI.IME I.F336/E $TRTOW.E_FIll TEST
61 N $IOEt.INE TEST5lTE-,_Cl:ieJ:lI_¢E$ _umemmm mmCII_JLAR IGV ---smunm mlm
teols3oow_
_t
130
50 80 125 200 315 500 800 1250 2000 3150 5000 8000FREQUENCY.HZ
t'/O_, 200 FT SIDELINE LF336,'E STATOlit.E_Fm TEST' 61 I¢$1DEI.II TEST51TE---WI_ RICES _Im_n Am
ClRCtI.RRI_ ---.mm_ m__000RRq
160
)
50 80 125 200 315 500 800 1200 2000 3150 5000FREQUENCY.HZ
FIGURE25 SEP,RATEDANDUNSEP,RATEDLF3361EPWLSPECTRAWITH CIRCULARIGV
39
I
1975010170-045
I ! _ 1 1I' ! : i
, I It
110200 FT $IOE.L.IH_ _ STRTOIK.E_JFMM1-cST ---tmmnmmo ;mint
_)_ 510F..I.INE TF.STSITE_ lINESHZ PtJE TONE CIRCtI.RR IOV ---wmmo mint5300 RPU
8 IW
/s
60 0 o 0 o e o o0 20 qo 60 80 100 120 IqO 160
RC_STIC RHGI.E.
120.200 FT $IOELIHE t.F336_ S'_TORU_ FI_4TEST
t_ $IOELINE TF..STSII_---NRSR R_$ _umemmo manHZ PURETONE CIRCUt.RRIGV ---sewm_ mm6000 RI_.
8sin..J
_100,
J.I.
_o ' ' ' _ ' _o _o'0 20 qO 80 100 1 1 _6CRCOUSTICRNGL,(,W.OI_E$
FIGURE26 SERRATEDANDIJIqS£RRATEDLF336/E BPF 113 OCTAVEBANDSPL DZRECTXVXTY PATTI:;P, NS MXTH CXRCIJLAR XGV
?
40
L
1975010170-046
I' I+
150 leT, ARC LF336/E STA_SS FAN TEST -- UNSERRATEDROTOR45,7 M, ARC TEST SITE--NASA AMES
--- -- SERRATED ROTOR20 Hz BAND_OTH clro,CULAR IGV60OO RPM
60 ° ACOUSTIC AN(N.,E• 110
_ 100
I+i8O
._ 70
6O0 1 2 3 4 5 6 7 8 9 10
FREQUENCY, Hz
110 ° ACOUSTIC ANGLE110 i
t i100 -
'80 •
_o60 - I I J f ! i I I I . ,_
0 1 2 3 4 5 6 7 8 9 lO
FREQUENCYI Hz I+
r
FIGURE 27 SERRATED AND UNSERRATED LF336/E NARROW.ANDSPECTRA NITHCIRCULARIGV /
1975010170-047
Y
! 1 I !Y
!
• t :
100.20(3FT SIDELINE LF336/E 5TATORLESSFRNTEbT --umemmm361 14SIDELINE TEST51TE--NRSRRILES160 HZ 1/3 O.B. CIRCULRR[C,V .... _o._0_
_J
f
50 -- o .., , , ,, • ,0 29 qO 60 60 100 120 lqO ISO
I_OUSTICFINC,LE. DEGREES
llO200 FT $IDELIME LF336/E 5TRTOI:ILE55FRNTEST _'61 N SIDELINE TEST5|TE--NI:ISI:II:IHES _ueemm, eo160 J'IZ 1/30.B. CIRCULRR[C,V -_-smu_
8 l°° moow. i,1
¢
o zo ,_b 8o eo :oo..... i_ _,=o leoRCOUSTICRN_E. DEGREES ,:
FIGURE 28 SERRATED AND UNSERRATED LF336/E WITH CIRCULAR IGV 160 Hz ,:
1/3 OCTAVE BAND SPL DIRECTIVITY PATTERNS
_' 42
!
1975010170-048
t
I00200 FT $10F.J.INE LF336/IE[STRTII_.IE55FII4 TIEST --UlmmmmSIDELINE TEST$[TE--NRSRRIqE5
CInCtLF_ IC,,VOI_H ,--tlZ1/_ O.O. --- mmunm
. -//"50 $ 0 ! e e e o
0 20 t_O 60 BO 100 120 lqO 160I1COUSTICRNGLE.DEGREES
tOO200 FT $10B.INE 1.1:336/1[STRTW4.trS$FFINTEST _umUmlm61 H $10ELINE TEST5ITE--I4F_ RHES1600 ItZ 1/30.O. CII_'IJI.I_IGV -.-smtmo6000 RI_
_TIC RN0i.E. {MOI_$
FXCUI_ 29 SER]_TEDANDUHSER]_TEDLF336/E WXTHCIRCULARIGV 1600 Hz1/3 OCTAVE BAND $PL DIRECT[VXTY PATTERNS
!
43
1975010170-049
100200 FT $10ELI?IE LF336/E 5TRTORLES$FRN TEST
_A_ SIDELINE TE5T SITE--NIqSR Ri,_S --um_mmmHZ 1/3 g.8. CIRCULAR lC,V .... _mmr:o5300 RPM
8 _'1 .3
' f1
_60
50 e e - e o e , o o
0 20 RQ 6Q 80 LQQ [20 L_O t60I:_OLP3T[CRNGLE, _EGI_IEE5
110 "200 FT SIDELINE LF'_J6/E, $TRTgSLE_3 FP,N TEqJT
_r_ SIOELINE TEST $ITE-_ I_ES --w_z_rreo1/3 @.B. CIRCULI_ IC,V ---uum_6000 1_5
-
I_"gUStlC I:INGLE, OEGREE$7
FIGURE 30 SERRATED AND UNSERRATED LF336/E WITH CIRCULAR [C" 2500 Hz _:
I/3 OCTAVE BAND SPL DIRECTIVITY PATTERNS#
44 ,,
1975010170-050
1oo200 FT _IOELIME L.F_/E STATUflL.ES5FAN TEST __
_ _IOELII4E TEST $|TF=--NI_R I:IHE5HZ 1/3 0.B. CIflCI.LI_ IGV .... smm_o5300I_
b
6O
0 qO 50 00 1130 120 t 0 150I:ICOUSTICI_I_.E. OEGIqEE$
100FT SlOELINE LF336/E 5TATC'_I.ESSFAN TEST _
§1 N $11_LIME TEbT 51_--NI_FI I_E$BOO0 ItZ 113 O.B. CII_.'UL.I_' IGV .... semmeoEO00Im14
s.®
.. |®
FICUU 31 $ERRA_D _ UNSELq3_TET)LF336/E WITH CIRCUL_ ICY 8000 ltZ1/3 OCTAVE BAND SPL DIP_CTIVITY PATTERNS
45
1975010170-051