Research Facilities > Tunnel facilities

garfield thomas water tunnel (GTWT) facilities

List of Facilities:

Description Closed Circuit, Closed Jet
Drive System 4-Blade Adjustable Pitch Impeller
Motor Power 2,000-hp Variable Speed (1,491 kW)
Working Section Maximum Velocity 18.29 m/s
Maximum and Minimum Absolute Pressures 413.7 to 20.7 kPa
Cavitation Number Range >0.1 dependent on velocity and/or J-range
Instrumentation Propeller dynamometers, 5-hole probes, pitot probes, lasers, pressure sensors, hydrophones, planar motion mechanism, force balances, accelerometers, acoustics arrays
Torque and Thrust Dynamometers Model internally mounted, 150-hp limit (111.85 kW)
Propeller or Model Size Range Model size from 76.2-mm to 635.0-mm inner diameter
Tests Performed Forces, flowfield, and pressure distributions on bodies of revolution, hydrofoils, propeller, etc.; cavitation performance and noise measurements of propellers, foils, hydrodynamic shapes, etc.; steady state and time-dependent force and torque measurements on powered models; flow visualization, body acceleration levels, shaft/body unsteady forces, and radiated noise
Other Remarks The tunnel turbulence level is 0.1 percent in test section. Air content can be controlled as low as 1 ppm per mole. Measurement can be made of hydrodynamic functions for stability and control of submerged vehicles. A directional hydrophone system is used for relative acoustic measurements.
Published Description

Lehman, ARL Penn State Report No. NORD 16597-56, Fluid Dynamics Department, Applied Research Laboratory, The Pennsylvania State University, 1959.

Marboe, R. C., et. al., "Hydroacoustic Research capabilities in the Large Water Tunnel at ARL-Penn State," Proceedings of Symposium on Flow Noise Modeling, Measurement, and Control, NCA-VOL 15/FED-VOL 168, pp. 125-135, ASME Winter Annual Meeting, 28 Nov-3 Dec., 1993.

Description Closed Circuit, Closed Jet
Test Sections
  1. Circular 304.8 mm dia. x 762.0 mm long
  2. Rectangular 508.0 mm x 114.3 mm x 762.0 mm long
Drive System Mixed Flow Peerless Pump
Motor Power 150 hp (111.8 kW)
Working Section Maximum Velocity 24.38 m/s
Maximum and Minimum Absolute Pressures 413.7 to 20.7 kPa
Cavitation Number Range >0.1 dependent on velocity
Instrumentation Lasers, pressure sensors, hydrophones
Model Size Range< 50.8-mm maximum diameter
Tests Performed Steady state and time-dependent force and pressure measurements on unpowered models; noise measurements on cavitating models; three-dimensional flow problems (circular section); two-dimensional flow problems (rectangular section); axial-flow pump tests
Other Remarks Independent gas control of air content; water filtration with 25-micrometer filters; intermittent operation with drag-reducing additive injection; partial neutralization of additive downstream of test section
Published Description Lehman, ARL Penn State Report No. NORD 16597-56, 1959.
Description Closed Circuit, Closed Jet
Drive System Axial-Flow Pump
Motor Power 25 hp (18.64 kW)
Working Section Maximum Velocity 21.34 m/s
Maximum and Minimum Absolute Pressures 861.9 to 20.7 kPa
Cavitation Number Range >0.1 dependent on velocity and pressure
Instrumentation Pressure transducers, lasers
Temperature Ambient
Tests Performed Effect of polymers on axial-flow pumps; surface roughness effects on cavitation; probe calibration
Other Remarks Air content by vacuum pump; water filtered through 25-micron filters as tunnel is filled
Published Description Kaku, M.S. Thesis, ARL Penn State, 1962.
Description Closed Circuit, Closed Jet
Drive System Centrifugal Variable Speed Drive
Motor Power 75 hp (55.9 kW)
Working Section Maximum Velocity 83.8 m/s
Maximum and Minimum Absolute Pressures 8,274.0 to 41.4 kPa
Cavitation Number Range >0.01 dependent on tunnel velocity
Instrumentation Pressure and temperature sensors, lasers.
Temperature 16°C to +176°C
Model Size Range 12.7-mm maximum diameter
Tests Performed Incipient and dissonant cavitation studies; development cavitation studies; cavitation damage
Other Remarks Stainless steel tunnel; bronze pump; three filter banks for removal of water, acids, solid particles (10 micrometers) depending on fluid media
Published Description Weir, Billet, and Holl, ARL Penn State TM 75-188, 1975.
Description Closed Circuit
Drive System Axial-Flow Blower Variable-Speed
Motor Power 150 hp (111.8 kW)
Working Section Maximum Velocity 45.72 m/s
Instrumentation Automatic scanning and rotating mechanisms, pressure sensors, hot wires, lasers, smoke generator
Tests Performed Pressure distributions over hydrodynamic shapes; velocity profiles in propeller planes; hot-wire measurements; wall-interaction effects on hydrofoils; flow visualization
Other Remarks The tunnel is subsonic and is used for basic and applied research. It is well instrumented for the measurement of model boundary layers and their wake turbulence.
Published Description Lehman, ARL Penn State Report No. NORD 16597-56, 1959.
Description Open Jet
Drive System Joy Axial-Flow Fan
Motor Power 20 hp (14.91 kW), 1,750 rpm
Working Section Maximum Velocity 36.58 m/s
Test Section 355.6 mm x 635.0 mm rectangular
Characteristics Porous-wall side suction of boundary layer, stagger angle (0° to 60°), incidence (±10°), solidity up to three
Instrumentation Lasers, hot wires, and pressure sensors
Tests Performed Blade-surface pressure distributions; boundary-layer and wake-pressure surveys
Other Remarks This facility is used for basic engineering research in turbomachinery blading.
Published Description Gearhart and Ross, ARL Penn State TM 506.2491-26, 1968.
Description 285-mm Constant Diameter Test Section, Closed Circuit
Drive System Gould Centrifugal Pump
Motor Power 100 hp (74.6 kW)
Working Section Maximum Velocity 6.096 m/s >9 m/s
Maximum and Minimum Absolute Pressures 586.0 to 101.4 kPa
Reynolds Number Range 4,000-15,000
Instrumentation Multipoint, multi-component laser Doppler velocimetry, particle image velocimetry, hot film anemometry
Tests Performed This facility models the turbulent flow of fluids next to a wall at a scale large enough to permit detailed flow measurement of the flow structure in the viscous sublayer.
Other Remarks Specially designed for research in viscous sublayer; wide Reynolds-number range for turbulent boundary layer research; 20 micrometer filters and heat exchangers; internal surface of test section honed to a 0.41 rms micrometer finish
Published Description Bakewell, Ph.D. Thesis, The Pennsylvania State University, 1966.
Chevrin, Ph.D. Thesis, The Pennsylvania State University, 1988.