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This dataset contains three-dimensional wind measurements (u, v, w) at 5 meters, as well as virtual temperature. These measurements are taken from the meteorological tower at Nantucket, with the instrument facing toward the southwest.
This dataset contains three-dimensional wind measurements (u, v, w) at 5 meters, as well as virtual temperature. These measurements are taken from the meteorological tower at Nantucket, with the instrument facing toward the southwest. The data have been standardized into NetCDF format.
Tower A is one of four subcanopy towers that were installed in the WREF canopy across a transect distance of 200m. Tower A had two CSAT3-3D sonics mounted at a height of 2.7m a.g.l. One (A1) is facing 290 degrees; the second (A2) is facing 90 degrees. The towers were installed to observe flow just above the forest floor and to identify any advection flows in the canopy. These data were also part of a larger ICOS project looking at forest flow coupling/decoupling with tower sites in Italy and Czech Republic.
Tower D is one of four subcanopy towers that were installed in the WREF canopy across a transect distance of 200m. Tower D had one CSAT3-3D sonic mounted at a height of 2.7 m a.g.l. The sonic is facing 290 degrees. The towers were installed to observe flow just above the forest floor and to identify any advection flows in the canopy. These data were also part of a larger ICOS project looking at forest flow coupling/decoupling with tower sites in Italy and Czech Republic.
Tower C is one of four subcanopy towers that were installed in the WREF canopy across a transect distance of 200m. Tower C had one CSAT3-3D sonic mounted at a height of 2.7 m a.g.l. The sonic is facing 270 degrees. The towers were installed to observe flow just above the forest floor and to identify any advection flows in the canopy. These data were also part of a larger ICOS project looking at forest flow coupling/decoupling with tower sites in Italy and Czech Republic.
Tower B is one of four subcanopy towers that were installed in the WREF canopy across a transect distance of 200m. Tower B had two CSAT3-3D sonics mounted at a height of 2.7 m a.g.l. One (B1) is facing 270 degrees; the second (B2) is facing 90 degrees. The towers were installed to observe flow just above the forest floor and to identify any advection flows in the canopy. These data were also part of a larger ICOS project looking at forest flow coupling/decoupling with tower sites in Italy and Czech Republic.
Peak wind speed recording device, which employs a drag disk with two constant-rate springs /high and low/ and a precision clutching mechanism, measures wind speeds from 8 m/sec up to 200 m/sec while retaining permanent record of peak wind. Device withstands temperatures up to 810 K.
Calibrator generates accurate flow velocities over wide range of gas pressure, temperature, and composition. Both pressure and flow velocity can be maintained within 0.25 percent. Instrument is essentially closed loop hydraulic system containing positive displacement drive.
Fabrication and testing of peak wind speed recording device
Gas velocity measuring instrument measures transport time of ion-trace traveling fixed distance between ionization probe and detector probe. Electric field superimposes drift velocity onto flow velocity so travel times can be reduced to minimize ion diffusion effects.
An instrument for measuring peak wind speeds under severe environmental conditions is described, comprising an elongated cylinder housed in an outer casing. The cylinder contains a piston attached to a longitudinally movable guided rod having a pressure disk mounted on one projecting end. Wind pressure against the pressure disk depresses the movable rod. When the wind reaches its maximum speed, the rod is locked by a ball clutch mechanism in the position of maximum inward movement. Thereafter maximum wind speed or pressure readings may be taken from calibrated indexing means.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
The S-193 oceanographic program is designed to demonstrate the operational feasibility of measuring ocean surface winds on a global basis with a composite radar-radiometer sensor. Near-simultaneous radiometric/scatterometric measurements offer a better opportunity to make improved estimates of surface winds through a variety of atmospheric conditions. Support is presented in developing interpretational techniques for the joint measurements, designing experiments to verify the joint interpretation techniques, predicting the observations from theory, evaluating system effects on the measurements, and developing system design criteria.
Device allows wind speeds to be measured with less power by alternating hot-wire or hot-film heating periods with measurement periods. System includes reference auxiliary circuits to generate V sub ref and ramp voltage (E sub 3) and reference half of bridge circuit. Circuit permits use of several sensing films with common temperature compensation sensor.
In the first practical application of laser anemometry to an actual gas turbine engine combustor, the mean velocity and turbulent intensity profiles were measured in a steady-flow combustion rig across an annulus simulating a turbine inlet; to establish a basis for comparison with similar measurements to be made in an operating engine and to confirm current turbine aerodynamics and heat transfer design assumptions. It was necessary to develop a new experimental technique for traversing the annulus due to differential thermal expansion of the cantilevered combustion rig and a new computer-graphics analysis technique for analyzing the velocity histograms due to the high background light intensity. The axial mean velocity and turbulent intensity were uniform across the annulus under all operating conditions and the flow had little or no swirl component. The isothermal mean velocity was doubled by the burning of fuel, however, the isothermal turbulent intensity was relatively unaffected.
Calibration tests using hot wires were conducted using a newly developed test rig that greatly reduced the data acquisition time. A comparison of measured and computed velocity vector magnitude and direction indicates the necessity of complete probe calibration to determine flow interference and/or operating limitation regions. Calibration results indicate that flow rates with 3 percent accuracy and flow angles with 5 deg accuracy are attainable.