Richard F. Bozak, Jr.

Glenn Research Center, Cleveland, Ohio

Advanced Noise Control Fan 

Aerodynamic Performance

NASA/TM—2009-215807

November 2009
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Richard F. Bozak, Jr.

Glenn Research Center, Cleveland, Ohio

Advanced Noise Control Fan 

Aerodynamic Performance

NASA/TM—2009-215807

November 2009

National Aeronautics and

Space Administration

Glenn Research Center

Cleveland, Ohio 44135
Available from

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7115 Standard Drive

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National Technical Information Service

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Level of Review: This material has been technically reviewed by technical management. 

Acknowledgments

The author would like to acknowledge the efforts of the Advanced Noise Control Fan (ANCF) support crew in the 

Aero-Acoustic Propulsion Laboratory, and also the assistance of Dr. Daniel Sutliff and Dr. Christopher Miller.
NASA/TM—2009-215807 1

Advanced Noise Control Fan Aerodynamic Performance 

Richard F. Bozak, Jr. 

National Aeronautics and Space Administration 

Glenn Research Center 

Cleveland, Ohio 44135 

Abstract 

The Advanced Noise Control Fan at the NASA Glenn Research Center is used to experimentally 

analyze fan generated acoustics. In order to determine how a proposed noise reduction concept affects fan 

performance, flow measurements can be used to compute mass flow. Since tedious flow mapping is 

required to obtain an accurate mass flow, an equation was developed to correlate the mass flow to inlet lip 

wall static pressure measurements. Once this correlation is obtained, the mass flow for future 

configurations can be obtained from the non-intrusive wall static pressures. Once the mass flow is known, 

the thrust and fan performance can be evaluated. This correlation enables fan acoustics and performance 

to be obtained simultaneously without disturbing the flow. 

List of Symbols 

a Ps static absolute pressure 

g Ps static gauge pressure 

a Pt total absolute pressure 

g Pt total gauge pressure 

Patm atmospheric pressure 

M mach number 

m& mass flow 

mcorr & corrected mass flow 

Tamb ambient temperature 

TSD standard day temperature 

A duct cross-sectional area 

R gas constant 

C calibration constant 

ΔPloss ICD pressure loss 

f friction factor 

ρ density of air 

L thickness of ICD honeycomb 

V velocity through the ICD 

D effective (pipe) diameter of the ICD area 
NASA/TM—2009-215807 2

ν kinematic viscosity 

m ICD pressure loss equation slope 

b ICD pressure loss equation offset 

Pthrust thrust power 

Pshaft shaft power 

Vavg average duct axial velocity 

η fan efficiency 

τ shaft torque 

ω fan speed 

Introduction 

The Advanced Noise Control Fan (ANCF) is a 4-ft diameter ducted fan used to measure and evaluate 

fan noise. It is located in the Aero-Acoustic Propulsion Laboratory (AAPL) at the NASA Glenn Research 

Center. The ANCF has a nominal inlet duct Mach number of approximately 0.15 when the fan is rotating 

at 1800 RPMC. The ANCF has a highly configurable duct arrangement that can be used to evaluate a 

variety of acoustic technologies (Refs. 1 and 2). 

The data presented in this paper were taken from baseline measurements obtained in early 2009, after 

new rotor blades and a new Inlet Control Device (ICD) were installed (Ref. 3). The ANCF baseline 

configuration consists of 16 rotor blades at a 28° pitch angle, with 14 stator vanes spaced 1 stator chord 

length behind the rotor. Along with this baseline configuration, measurements were also taken with the 

same rotor configuration without stator vanes. 

The ANCF offers a variety of static and total pressure probes, which when used with the 

Electronically Scanned Pressure system (ESP), can obtain very accurate pressure measurements. The 

ESCORT data acquisition system is used to record the pressure. Along with the pressure measurements, 

ambient temperature and atmospheric pressure measurements give additional data that is necessary for 

flow computations. Constant Temperature Anemometry (CTA) measurements measure axial as well as 

tangential flow. The Probe Actuator and Control System (PACS) is used to position the probes into the 

flow at different radii. 

The versatility of the ANCF duct allows for flow measurements to be taken in different axial 

locations. In order to correlate inlet duct wall static pressure to mass flow, pressure measurements are 

taken throughout the ANCF duct. The duct measurement schematic, shown in Figure 2, locates total and 

static pressure traverses in the inlet and aft sections, as well as a hotfilm traverse to find the swirl angle. 

This paper will present the instrumentation, configurations, and equations used to make the mass flow 

correlation. An accompanying uncertainty analysis will show the quality of the correlation. Beyond the 

mass flow correlation, the aerodynamic performance of the ANCF rig will be evaluated. 
NASA/TM—2009-215807 3

Figure 1.—ANCF Duct 

Figure 2.—ANCF Duct Flow Measurement Schematic 

Instrumentation 

Inlet Lip Wall Static Pressures 

The ANCF has eight static pressure ports in the inlet lip. The ports are equally spaced 

circumferentially around the lip. The inlet lip static pressure ports were designed and installed such that 

the orifice induced error is negligible (Ref. 4). The cylindrical taps have a 0.0421 in. (1 mm) inner 

diameter square edge tube insert which is perpendicular to the flow and flush to the duct wall. 
NASA/TM—2009-215807 4

Figure 3.—Short and Long Static Pressure Probes

Static Pressure Probes 

Inlet static pressure measurements were taken with a 90° style static pressure probe. The probe has a 

bullet nose at the leading edge and holes circumferentially located around the tube at the measurement 

point. This probe measures the static pressure 2-1/4 in. in front of the insertion point. This probe is the 

“short static” shown in Figure 3. 

Aft static pressure measurements were taken with a longer static pressure probe to measure the static 

pressure 3-1/8 in. in front of the insertion point. Since static pressure probes are sensitive to the yaw 

angle, the probe was directed into the flow. This probe is the “long static” shown in Figure 3. 

Total Pressure Probes 

Inlet total pressure measurements were taken with a Kiel type probe (United Sensor KAC-12). This 

probe has a yaw capture angle of ± 52°. 

The aft total pressure measurements used to define the hub and outer wall boundary layers were taken 

with a total pressure probe with the geometry shown in Figure 4. This probe was rotated into the 

incoming flow angle to ensure accurate measurements. 

Total Pressure Rake 

Free-stream aft total pressure measurements were taken with a total pressure rake which consists of 

six fixed radially spaced Pitot probes. For measurements without stator vanes, the capture angle of these 

Pitot probes is insufficient due to the > 25° swirl angle. Therefore, an attachment was made to increase 

the capture angle on the total pressure rake. The geometry of the rake Pitot probes and attachment are 

show below in Figure 4. A single Pitot probe with the same geometry as the total pressure rake was tested 

with and without the attachment in a small flow jet. The results of this test are shown in Figure 5. The 

yaw capture angle was calculated as being the angle where there is a 1% error in the pressure 

measurement (Ref. 5). The addition of the probe attachment increased the positive capture angle from 

approximately 15° up to 21°. 
NASA/TM—2009-215807 5

Figure 4.—Drawing of Total Pressure Rake Attachment 

Figure 5.—Total Pressure Probe Yaw Angle Sensitivity 

Constant Temperature Anemometry (CTA) Probe 

Flow angle measurements were taken with a two-channel hot-film probe. This probe was calibrated 

with a low-turbulence free jet calibrator. The accuracy of this flow angle measurement primarily depends 

on the ability to align the probe axially in the ANCF duct. 

-0.1

-0.09

-0.08

-0.07

-0.06

-0.05

-0.04

-0.03

-0.02

-0.01

0

0 5 10 15 20 25 30 35 40

Yaw Angle (deg)

Error

Pitot

3/8" OD 30 deg

Δ Pt 

q
NASA/TM—2009-215807 6

Motor Measurements 

The variable speed motor drive controller outputs the torque delivered by the motor. The fan speed is 

measured by an encoder on the drive shaft, which is read by a Newport signal conditioner and then by 

ESCORT. 

Equations 

The mass flow correlation is based on the relationship of inlet wall static pressure to the mass flow. A 

ratio was defined to relate the inlet and aft mass flow calculations. This ratio is referred to as the 

calibration constant. The non-intrusive inlet measurements were used to find an estimated mass flow, 

while the aft flow mapping gave a measured mass flow. Once the inlet and aft mass flows are calculated, 

the calibration constant can be found. 

)(Measured

)(Estimated

Aft

Inlet

m

m C &

& = (1) 

Mass Flow Calculation 

The correlation between the inlet wall static pressure and mass flow is based on isentropic and ideal 

gas assumptions. This correlation is made by comparing the mass flow calculated from the inlet wall 

static pressure ports and the mass flow calculated from aft pressure measurement maps. At any location in 

the flow, the local Mach number can be found from the pressure ratio with the following equation. 

2

7

2

5

1

−

⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛

+=

M

P

P

a

t

a

s (2) 

The pressures measured by the inlet wall static pressure ports are proportional to the free stream static 

pressure. Therefore, this static pressure and free stream total pressure can be used to calculate a Mach 

number that is proportional to the average inlet duct Mach number. Unlike in the inlet, aft pressure 

measurements were taken at a variety of radial and circumferential locations to give the Mach number 

distribution across the exit plane. Once the Mach number is known, the mass flow can be calculated. 

Using the ideal gas law and speed of sound for an ideal gas with a ratio of specific heats of 1.4 for air, 

Equation (3) is formulated. All velocities and mass flows presented are corrected to standard day. 

⎥

⎥

⎥

⎥

⎦

⎤

⎢

⎢

⎢

⎢

⎣

⎡

− ⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛ =

−

1 7 7

2

amb a

t

a a s s P

P

RT & APm (3) 

m

T

T

m SD & &

amb

corr = (4) 

An estimated inlet mass flow is calculated from the inlet static pressure at the wall, the ICD pressure 

loss, ambient temperature, and atmospheric pressure measurements. This estimated mass flow is 

proportional to the measured mass flow. The measured mass flow is calculated from aft pressure 

measurement maps. The mass flow can be found by dividing the estimated inlet mass flow by the 
NASA/TM—2009-215807 7

calibration constant. Flow measurements were taken with corrected fan speeds between 1400 and 2000 

rpm to give a range of duct Mach numbers for the mass flow correlation. 

ICD Pressure Loss Equation 

The ICD adds a pressure drop to the flow path of the ANCF duct. When calculating the mass flow 

through the inlet, the ICD pressure drop is needed to find the total pressure inside the ICD. Since the mass 

flow must be calculated using only the inlet lip wall static pressure measurements, an equation was 

developed to account for the ICD pressure drop. Using the energy equation, a friction loss equation as a 

function of mass flow was developed for laminar flow through the ICD: 

D

LV

fP 2

2

avg

loss

ρ =Δ (5) 

m

D

L P & 4 loss

128

π

ν =Δ (6) 

where ΔPloss is the pressure drop across the ICD, ν is the kinematic viscosity of air, L is the thickness of 

the ICD honeycombs, D is the effective pipe diameter of the entire ICD area, and m& is the mass flow 

through the ICD. 

Since the geometry of the ICD is constant, the total pressure drop across the ICD is proportional to 

the mass flow. The small ANCF operating range allows for the relationship between ICD pressure drop 

and inlet lip wall static pressure to be linearized. A linear equation was fit to the data to obtain an 

equation for the ICD pressure drop from the inlet wall static pressure. 

bPmP g

loss s +⋅=Δ (7) 

Fan Efficiency Calculation 

Once the mass flow is calculated, the performance of the fan can be analyzed. The ANCF is driven by 

a 200 hp electric motor. The fan’s thrust power is a product of the thrust and velocity out of the duct. 

Instead of calculating a correlation for the velocity, the average velocity is found from correlated mass 

flow, density, and area. Although the corrected mass flow and velocity are used in the mass flow 

correlation, the mass flow and velocity are calculated to analyze the fan performance. The fan’s output 

power is calculated from combining thrust and power equations. 

2

thrust avg 2

1 = &VmP (8) 

The mass flow correlation allows for the fan’s output power to be calculated from the inlet duct wall 

static pressure. Since the fan’s efficiency is dependent upon the input power to the fan as well as this 

output power calculation, the input shaft power is calculated from the fan speed and the torque. The fan 

speed is measured from an encoder on the fan shaft, while the torque is an output from motor drive 

controller. The fan efficiency equation, shown below, was used to analyze the performance of the ANCF 

in a variety of configurations. 

Thrust Vm avg = & (9) 
NASA/TM—2009-215807 8

τω

=η 2

2 Vm avg & (10) 

Mass Flow and Fan Efficiency Equations for ESCORT 

In order to calculate mass flow and fan efficiency without detailed flow mapping, equations were 

developed to be implemented in the ESCORT data acquisition system. The corrected mass flow is 

calculated from atmospheric and gauge pressure measurements as well as an ambient temperature 

measurement. The eight circumferentially spaced inlet lip wall static pressure ports were used to divide 

the inlet flow into eight equally sized areas. The mass flow correlation equation incorporates each of these 

measurements to obtain the total mass flow. 

( ) ∑

=

−

⎥

⎥

⎥

⎥

⎥

⎦

⎤

⎢

⎢

⎢

⎢

⎢

⎣

⎡

⎥

⎥

⎥

⎥

⎦

⎤

⎢

⎢

⎢

⎢

⎣

⎡

− ⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛

++

+ + =

8

1

7

2

atm

atm

amb

atm

corr 1 7

8 i

g s

g

SD s g s

PbmP

PP

R

T

CT

APP

m

i

i i & (11) 

Once the corrected mass flow is known, the thrust and fan efficiency can be calculated. The average 

velocity can easily be found from the corrected mass flow and used to find the thrust. The fan efficiency 

can then be found by combining Equations (9), (10), and (12) to yield Equation (13). 

( ) atm

2

amb

2

corr Thrust

PPAT

RTm

g

SD s + = & (12) 

+ τω

=η

2

3 2

atm

2

23corr 2

7

amb

)(2 SD

g

s TPPA

& RmT

 (13)

Uncertainty Analysis 

Measurement Errors 

The measurement uncertainties of each instrument and data acquisition system were examined to 

determine the total uncertainty of the mass flow correlation. The static and total pressure probes and ports 

were designed and installed such that the probe error associated with the measurements is negligible 

(Refs. 4 and 6). 

The accuracy of the ESP pressure measurements is ±0.1% of 10 in. of water, which gives an accuracy 

of ± 0.00036 psi. Along with these gauge pressure measurements, the atmospheric pressure is also 

measured with an accuracy of ± 0.01 psia and the ambient temperature is measured with an accuracy of 

± 0.36 °F. The ESCORT data acquisition system adds an uncertainty of ± 0.05% of full scale to the 

atmospheric pressure and ambient temperature measurements. The total uncertainty on the atmospheric 

pressure and ambient temperature measurements becomes ± 0.014 psi and ± 0.37 °F respectively. 

Aft swirl angles were measured using a 2-channel hotfilm probe. The hotfilm calibration and 

accompanying data acquisition system errors were judged to be minor compared to the probe installation 

alignment error. Therefore, the swirl angle accuracy is the probe installation error, which was estimated as 

± 2°. 
NASA/TM—2009-215807 9

The fan’s input power is calculated from torque and fan speed measurements. The motor drive 

controller outputs the torque, with an accuracy of ± 2.9 ft·lb. The fan speed is measured by an encoder on 

the drive shaft, which is read by a signal conditioner and ESCORT. The combined accuracy of this 

measurement is ± 3 rpm. 

Calculation Errors 

The quality of the mass flow correlation and fan efficiency calculation were analyzed by performing 

an uncertainty analysis as specified in ASME PTC 19.1 (Ref. 7). Figure 6, below, shows the contributions 

of the individual measurement errors to the calculation errors. This analysis was done for a nominal 

corrected fan speed of 1800 rpm. The individual inlet pressure and temperature measurement errors 

contribute to an uncertainty of ± 0.34 lbm/s on the inlet lip mass flow calculation. The individual aft 

measurement uncertainties give an accuracy of ± 2.5 ft/s on the aft corrected velocities as well as an 

accuracy of ± 2.1 lbm/s on the calculated aft mass flow. The combination of the calculated inlet and aft 

mass flows gives an accuracy of ± 0.023 on the calculated calibration constants. Since the calibration 

constant is the average of four measurements over a range of flows, the entire mass flow correlation has 

an accuracy of ± 1.6 lbm/s. When calculating output power of the fan, the velocity and mass flow 

uncertainties give the power calculation an accuracy of ± 2.2 hp. Since the input power is calculated from 

the encoder and torque output, it has a combined accuracy of ± 1.0 hp. The combination of input and 

output power errors gives a combined uncertainty on the efficiency calculation of ± 1.9%. 

Results 

Inlet Duct Flow 

The inlet pressure traverses were obtained with the short static and Kiel type pressure probes. Figure 

8 shows the variation in total and static pressure over the length of the traverse. Since the wall static 

pressure is significantly lower than the static pressure throughout the traverse, the calibration constant 

will be greater than 1. The total pressure traverse shows that total pressure measurements 14 in. from the 

outer wall are sufficiently in the free-stream for ICD pressure drop measurements. 

ICD Pressure Drop 

The total pressure drop due to the ICD losses was found by measuring the free stream total pressure 

upstream of the fan with a Kiel type total pressure probe. The relationship between wall static and free 

stream total pressure for each fan speed and vane configuration at a location of 14 in. from the outer wall 

is shown below in Figure 8. The linear regression of the data gives a slope of 0.015 and an offset of 

0.0007 psig. The error bars show that the linear approximation holds within the uncertainty of the 

pressure measurements. 

Inlet Duct Mass Flow Calculation 

The mass flow through the inlet duct was calculated using Equations (3) and (4). The eight static 

pressure measurements and the free stream total pressure were used to find eight corrected velocities. The 

duct area was divided into eight equally sized pie shaped areas. The velocities and their corresponding 

areas were used in conjunction with the density of the air at the measured ambient temperature to obtain 

the mass flow through each section. Subsequently, the mass flow through the entire inlet is found. The 

inlet mass flow, corrected to standard day, over a range of corrected fan speeds is shown below in 

Figure 9. 
Figure 6.—Error Contributions 

NASA/TM—2009-215807 

1

0
NASA/TM—2009-215807 11

Figure 7.—Inlet Total and Static Pressure Traverses at 1800 RPMC 

 

Figure 8.—ICD Pressure Drop data and linear fit 

ΔPloss= 0.015Ps

g

 + 0.0007 
NASA/TM—2009-215807 12

Figure 9.—Estimated Inlet Mass Flow with and without stator vanes 

Uncertainty is ±0.34 lbm/s 

Figure 10.—Aft Section Swirl Angle at 1800 RPMC
NASA/TM—2009-215807 13

Aft Flow 

Aft Swirl Angle 

The swirl angle was measured in the aft section with a hot-film probe to examine the effect of the 

stator vanes on the swirling flow, as well as to determine the axial velocity component used in the axial 

mass flow calculations. The measured swirl angle in the aft section is shown below in Figure 10. The 

addition of 14 stator vanes spaced 1 chord behind the rotor reduced the swirl angle by about 20°, but not 

all the way to zero. 

Aft Flow Mapping 

Aft flow mapping was done in detail with the total pressure rake. The rake was rotated around the 

duct in increments of 45° to give 8 circumferential measurement locations, as shown in Figure 2. These 8 

circumferential locations combined with the 6 radial pressure measurement locations on the rake give 48 

free-stream total pressure measurements. 

Additional total pressure measurements were taken with PACS at fixed locations to define the hub 

and outer wall boundary layers. Two measurements were taken to define the hub boundary layer, while 

three measurements were taken to define the outer wall boundary layer. These measurements were taken 

at the 270° circumferential location to measure behind an upstream stator vane and at 180° to measure 

between two upstream stator vanes. The 58 boundary layer and free-stream total pressure measurements 

were used to map the flow exiting the ANCF duct. 

Static pressure measurements were also taken with PACS traverses at the 180° and 270° 

circumferential locations. These measurements were used to define the aft static pressure profiles. The 

measurement locations were identical to those of the free-stream and boundary layer total pressure 

measurements. 

The total and static pressure measurements were used in conjunction with Equation (2) to obtain a 

Mach number at each location. The Mach number and flow angle were then used to calculate a corrected 

axial velocity at each of the total pressure measurement locations. This corrected axial velocity was 

mapped and is shown below in the contour plots of Figure 11. 

Since the 8 circumferential rake locations overlap the 14 stator vanes twice, the plots with the stator 

vanes installed show a flow variation that repeats itself around the duct. This flow variation is an example 

of spatial aliasing. The data can then be assumed to be periodic about each stator vane, and the plots can 

be collapsed to show the flow variation over two stator periods, as shown below in Figure 12. While the 

flow without stator vanes is fairly uniform, the figures on the right, the addition of stators causes 

variations in the flow that are periodic about the stators, as shown in the figures on the left. The stator 

vanes create a flow separation, and slower flow, near the center-body. 
NASA/TM—2009-215807 14

 a) 14 Stator Vanes b) 0 Stator Vanes 

 

 

 

 

Figure 11.—Aft Axial Corrected Velocities, ft/s, with (a) and without (b) Stator Vanes 

1400 

RPMC 

1600 

RPMC 

1800 

RPMC 

2000 

RPMC 
NASA/TM—2009-215807 15

a) 14 Stator Vanes b) 0 Stator Vanes 

 

 

 

 

Figure 12.—Collapsed Aft Axial Corrected Velocities, ft/s, with (a) and without (b) Stator Vanes 

2000 

RPMC 

1800 

RPMC 

1600 

RPMC 

1400 

RPMC 
NASA/TM—2009-215807 16

Figure 13.—Aft Measured Mass Flow 

Uncertainty is ±2.1 lbm/s 

Aft Duct Mass Flow Calculation 

The mass flow at the exit plane of the exhaust duct was calculated using Equations (3) and (4). The 6 

radial locations and 8 circumferential locations give 48 different points. The Mach number of the flow at 

that location was calculated from the total and static pressure corresponding to each of these points. The 

aft duct area was divided into 8 pie sections, and then subdivided into 6 rings to give each measurement 

an area. The mass flow through the boundary layers was similarly divided into two additional rings 

around the hub and 3 additional rings at the outer wall. These rings were subdivided with the two 

circumferential traverses to map the boundary layer around the duct. These areas were used in 

conjunction with the Mach number, ambient temperature and atmospheric pressure to calculate the mass 

flow exiting the duct. The mass flow for each configuration at each of the four corrected fan speeds is 

shown below in Figure 13. 
NASA/TM—2009-215807 17

Figure 14.—Calibration Constant 

Uncertainty is ± 0.023 

Mass Flow and Fan Performance 

Calibration Constant 

The calibration constant, defined in Equation (1), is the result of dividing the estimated inlet mass 

flow by the measured aft mass flow. The calibration constant for each configuration and fan speed is 

shown below in Figure 14. The average of these calibration constants was found to be 1.221. Since the 

calibration constants have an uncertainty of ± 0.023, a higher order correlation will not improve the 

accuracy. Although the correlation is sufficient for a single configuration, the difference in flow with and 

without stator vanes creates an offset between the calibration constants that is twice as large as the 

uncertainty, and is yet unexplained. 

Fan Performance and Efficiency 

The ANCF’s input power is calculated from fan speed and torque measurements, while the output 

power is calculated from the flow measurements. The calculation of the fan’s input power does not take 

into account bearing losses. The fan performance is shown below in Figure 15. While the input power is 

slightly higher without stator vanes, the output power is lower. Therefore, the fan efficiency is 

approximately 10% lower when the stator vanes are removed. This inefficiency is due to the energy lost 

swirling flow and the thicker boundary layers. The fan efficiency over the range of fan speeds for each 

configuration is show in Figure 16. 
NASA/TM—2009-215807 18

Figure 15.—Fan Performance 

Figure 16.—Fan Efficiency 
NASA/TM—2009-215807 19

Summary 

The mass flow correlation used was demonstrated to be an accurate method for correlating inlet lip 

wall static pressure measurements to mass flow. The fan performance can be analyzed in future ANCF 

configurations without taking the time for detailed flow measurements and calculations. The inlet lip wall 

static pressure measurements allow for acoustics and flow to be analyzed simultaneously. 

References 

1. Heidelberg, L.J., Hall, D.G., Bridges, J.E., and Nallasamy, N., “A Unique Ducted Fan Test Bed for 

Active Noise Control and Aeroacoustics Research”, NASA TM–107213, also AIAA–96–1740. 

2. Loew, R.A., Lauer, J.T., McAllister, J., and Sutliff, D.L., “The Advanced Noise Control Fan”, 

NASA/TM–2006-214368, also AIAA–2006-3150, Nov 2006. 

3. McAllister, J., Loew, R.A., Lauer, J.T., and Sutliff, D.L., “The Advanced Noise Control Fan Baseline 

Measurements”, AIAA 2009-624-779. 

4. The American Society of Mechanical Engineers Performance Test Code: Pressure Measurement. 

ASME PTC 19.2-1987. 

5. W. Gracey, W. Letko, and W. R. Russell, “Wind Tunnel Investigation of a Number of Total-Pressure 

Tubes at High Angles of Attack,” NACA TN 2331, Apr. 1951. 

6. Holman, J. P., Experimental Methods for Engineers: Seventh Edition, McGraw-Hill, pp. 331-340, 

2001. 

7. The American Society of Mechanical Engineers Performance Test Code: Test Uncertainty. ASME 

PTC 19.1-2005. 
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5a. CONTRACT NUMBER

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)

Bozak, Richard, F., Jr. 

5d. PROJECT NUMBER

5e. TASK NUMBER

5f. WORK UNIT NUMBER

WBS 561581.02.08.03.18.02 

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

National Aeronautics and Space Administration 

John H. Glenn Research Center at Lewis Field 

Cleveland, Ohio 44135-3191 

8. PERFORMING ORGANIZATION

 REPORT NUMBER

E-17070 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

National Aeronautics and Space Administration 

Washington, DC 20546-0001 

10. SPONSORING/MONITOR'S

 ACRONYM(S)

NASA 

11. SPONSORING/MONITORING

 REPORT NUMBER

NASA/TM-2009-215807 

12. DISTRIBUTION/AVAILABILITY STATEMENT

Unclassified-Unlimited 

Subject Category: 01 

Available electronically at http://gltrs.grc.nasa.gov 

This publication is available from the NASA Center for AeroSpace Information, 443-757-5802

13. SUPPLEMENTARY NOTES

14. ABSTRACT

The Advanced Noise Control Fan at the NASA Glenn Research Center is used to experimentally analyze fan generated acoustics. In order to 

determine how a proposed noise reduction concept affects fan performance, flow measurements can be used to compute mass flow. Since 

tedious flow mapping is required to obtain an accurate mass flow, an equation was developed to correlate the mass flow to inlet lip wall 

static pressure measurements. Once this correlation is obtained, the mass flow for future configurations can be obtained from the nonintrusive wall static pressures. Once the mass flow is known, the thrust and fan performance can be evaluated. This correlation enables fan 

acoustics and performance to be obtained simultaneously without disturbing the flow.

15. SUBJECT TERMS

Noise; Fan; Aerodynamic 

16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

 ABSTRACT

UU 

18. NUMBER

 OF 

 PAGES

25 

19a. NAME OF RESPONSIBLE PERSON

STI Help Desk (email:help@sti.nasa.gov) 

a. REPORT

U 

b. ABSTRACT

U 

c. THIS 

PAGE

U 

19b. TELEPHONE NUMBER (include area code)

443-757-5802 

Standard Form 298 (Rev. 8-98)

Prescribed by ANSI Std. Z39-18