FRAP Air
High-resolution frequency measurement system
Slim design compatible with 4- and 5-holeprobe heads
Robust design with stainless steel
housing and Lemo connector
Figure 1: FRAP Air

Measurement frequencies up to 2 kHz

Probe head options
The FRAP Air is configurable in different multi-holeprobe options. This includes 4- and 5-hole probes.
The pressure distribution on the probe tip will becorrelated to individual wind tunnel calibrations todetermine static pressure, total pressure, and thevelocity components/flow angles.

GeneralWeight probe shaft~200 gDimension probe

Probe options

Head: 60 mm x Ø 3 mm
5-hole probe:
230 mm x Ø 20 mm
4-hole probe:
210 mm x Ø 20 mm
4- and 5-hole probe heads

Geometry

Straight, L-shaped, Cobra

Tip diameter

Typ. 3 mm … 5 mm

The probe can be equipped with freely customized
probe shapes, due to the design freedom in additive
manufacturing. Hence, shape and size can beadapted to any installation or access to flow pathsituation. Shape and length of the probes head will
determine the applicable measurement frequency.

Environmental Conditions
Operatingtemperature-20 ... 70 °C (-4 … 158 °F)

Operating medium

Air and other non-corrosive
gases

Humidity

0 ... 95 %, non-condensing

Figure 2: Shape examples (top to bottom:cobra probe, straight probe, L-shaped probe)

GeneralThe FRAP Air from Vectoflow make it possible todetect high-frequency flow phenomena in the kHz
range This makes it the ideal choice formeasurements of:
••
•
•
•

3D turbulence spectra
Time resolved high frequency
measurements
Shock events
Unsteady aerodynamics of rotating
systems
CFD Validation

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Version: 2023-04-17

Sensors and Electronics

Pressure Acquisition
Pressure acquisition

4 or 5 differential pressure
sensors

Pressure sensor
accuracyMax. +/- 0.25 % FSS(typical +/- 0.1 % FSS)

Sensor Options
Differential pressure
range (kPa)Max. Mach number

2.00

0.17

6.90

0.30

Frequency calibration
The frequency response depends on the acousticalbehavior of the pressure line and the dynamic
behavior of the sensor. This will be determined in an
acoustic chamber, which will compare the dynamic
behavior of the probe to a known reference. The
resulting transfer-functions are used to correct thepressure signals.

Measurement Errors
Flow angles< 1°Velocities< 1.0 m/s or < 1.0 %,whichever is greater

The FRAP AIR is equipped with 4 or 5 differential
pressure sensors close to the probe tip. All
differential pressure sensors can be selected bypressure range. The temperature-compensatedpressure transducers feature high accuracy and aminimal offset drift. The high proof pressure provides
sufficient protection against accidental overloads.

System solution
Vectoflow provides a complete system solution for
velocity measurements.

Interfaces (DAQ System)
Supply voltage

5 V USB Type Aor 5 – 13 V
2 BNC-Inputs for probe
triggering

Trigger Input
Probe connection

Up to 4 probes (LemoEGG.0B.309)

Cable (included)

Lemo (FGG.0B.309) toUSB
NI-USB 6210

Acquisition hardware

The Fast Response measuring system includes:
•••
•
•
•

Fast Response Probe
Cabling and Connection
AD-Converter
Post-Processing Software
Calibration Data
Consulting for Data Evaluation

Interfaces
Supply voltage± 12 – 18 V + GND

Pressure reference
port

Metal tube for reference
pressure ⌀ 1.6 mm

Cable (included)

Lemo Type (FGG.0B.309)

Acquisition hardware

Compatible with any±10 V ADC

Frequency Calibration
Calibration system

Acoustic calibration

Frequency range

Up to 2 kHz (depending onprobe geometry)

Transfer function
frequency step size

CustomContact
Vectoflow GmbH, Germany
T: +49 89 124149570
M: info@vectoflow.com
w: www.vectoflow.com
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Version: 2023-04-17