4CTA Hot-Wire Measurement System

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Key features

• High-dynamic measurements of flow velocities
• Velocity range: 0.1 – 50 m/s in air, higher velocities and other gases possible
• Measurement accuracy: 0.1 m/s + 0.5% FS (v < 20 m/s) / 1% FS (20 < v < 50 m/s)

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About the 4CTA Hot-Wire Measurement System

The 4CTA measurement system is a 4-channel hot-wire anemometer for simultaneous operation of up to 4 hot-wire probes. The hot-wire bridges are used for dynamic measurements of flow velocities in air (eCTA) and for the fast measurement of flow temperatures (eCCT). The calibrated velocity range in air reaches up to 50 m/s.

Due to the measurement principle the hot-wire anemometer is especially qualified for small flow velocities and transient or more specifically dynamic processes. The system is ready to use on delivery as the included probes are already adjusted and calibrated.

The signals of the hot-wire probes are directly gathered by the intern USB-data acquisition and are converted
into velocities or temperatures. By decoupling the fluctuations towards headphones, an intuitive sensation of the flow condition can be gained. As the ear is a good frequency analyser this is one of the most effective methods for the investigation of aero-acoustic problems. In addition, a barometrical pressure sensor and a PT100 signal transducer are incorporated. The free analogues and digital in- and outputs of the data acquisition card can be connected onto customer-specific connectors to enable the connection of further sensors.

Data Acquisition and Hot-Wire Measurement System

The measurement chain consists of four components:
Hot-wire probe – Hot-wire bridge – Supply and signal conditioning unit – A/D-converter.

Probe and bridge form a unit which must be calibrated as such. It must be considered that probe and bridge are in tune with each other and hence an elongation of the sensor cable is not possible. The connection cable of the eCTA-bridge can be customized.

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