MiniCTA / Multichannel CTA Anemometer System
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MiniCTA and Multichannel CTA Systems Compact CTA Systems for accurate flow investigations Applications Flow velocity and turbulence measurements For applications in air (up to 100 m/s) and in water Educational, industrial and scientific applications Can be used with both wire and fiber/film probes depending on application. Multipoint measurements in e.g. boundary layer studies or in studies of coherent structures. Bandwidth ~10 kHz for wire probes in air Up to 20 m cables can be used. Easy to use and easy to learn software – calibration, data acquisition, traversing, data reduction, database and graphical display in a single platform Velocity and directional calibration of probes Various Calibration Systems ensuring high accuracy. MiniCTA Anemometer package includes all the basics to get started in velocity measurements: MiniCTA channel, software, manuals, 2 hotwire probes and necessary cables delivered in a suitcase. Introduction Constant Temperature Anemometer (CTA) technology is a well-established measurement technique with commercial systems available since 1958. The measurement principle is based on the cooling of small sensors placed in a flow. The temperature (resistance) of the sensor is kept constant by an advanced feedback control loop that contains an electronic bridge circuit. This way, the anemometer produces a continuous voltage that is proportional to the instantaneous flow velocity. The output signal is sampled with high enough resolution to analyse the fluctuations in the frequency domain. Even though CTA technique is intrusive and non-linear in response, it is still the best instrument for the accurate determination of high frequency flow fluctuations, boundary layer diagnostics, simultaneous multi-point velocity and temperature measurements. Description The MiniCTA and Multichannel CTA systems offer a cost-effective solution for measurement of flow and turbulence in applications with low to medium flow velocities and moderate fluctuation frequencies. Both platforms contain the same circuit board and therefore share the same specifications for velocity channels. The MiniCTA system is the single-channel version and is ideal for new CTA users and for more experienced users demanding mobility. The MiniCTA system is also well suited for demonstration of CTA in undergraduate fluid dynamics laboratory classes. MultichannelCTA systems offer more functionality than their single-channel counterparts. They are normally configured with a number of velocity channels and a temperature channel. Both systems are operated by the StreamWare Basic software, which performs setup, automatic probe calibration, data acquisition, data conversion

MiniCTA & MultichannelCTA MiniCTA MiniCTA is a single channel anemometer optimized for moderate-speed airflow and low-speed water flow measurements. Air velocities up to 100m/s and water velocities up to 2m/s can be measured. The frequency bandwidth reaches above 10 kHz at 50 m/s in air. The unit is also designed for use with probes suited for water applications. Product Information or Ethernet and the calibration process is controlled from StreamWare Basic software. The manual calibrator supports a two-point calibration scheme as well as a multi-point calibration scheme. Both calibrators...

MiniCTA & MultichannelCTA Product Information MiniCTA temperature module A compact thermistor and amplifier package (54T40 and 90P10) is available for measurement of slow temperature changes. This package is especially useful for standalone MiniCTA- (single-channel) and MultichannelCTA systems without temperature channels (4-channel and 8channel versions). With this package one can perform temperature correction to improve measurement accuracy in flows with temperature variations. Completing the measuring chain - Probes Dantec Dynamics’s standard hotwire and hotfilm probes are supported by...

MiniCTA & MultichannelCTA Product Information System Computer Database for organised measurements and results The MiniCTA and MultichannelCTA systems can be delivered with a system computer, a portable or a desktop version, which is preconfigured, tested and ready to use. All necessary hardware and software installation is performed before delivery. StreamWare Basic organizes the measurement setups and stores them in a dedicated database. The complete measurement task from configuration and experiment layout to acquiring, reducing and storing data is performed in an intuitive way. The user...

MiniCTA & MultichannelCTA Product Information MiniCTA & MultichannelCTA Product Information Advanced set up defining Hardware, Scheduling of data acquisition, Conversion & Reduction Data conversion and reduction Raw data are converted into velocity samples and further decomposed into velocity components in the case of multi-sensor probes, based on the calibration data. Data reduction comprises analysis in both the amplitude and the time (spectral) domain selected in a data reduction dialogue box. Reduced data are stored separately and are always available for graphical...