Experiment ID
| FZK hydrogen distribution tests in free turbulent jet
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Short Description
| Hydrogen distribution tests in horizontal free turbulent jet have been carried out in a compartment with an internal volume of 160 m3. Experimental facility consisted of high pressure gas system to provide hydrogen release at pressures in the range 20 – 260 bar through the nozzle (Figs. 1, 2).
Figure 1 Hydrogen injection system Figure 2 Side view of the experimental set-up Figure 3 Hydrogen and velocity distribution in free jet Hydrogen concentration profile and flow velocity were simultaneously measured in three different cross-sections at distances 0.75, 1.5, and 2.25 m from the nozzle (Fig. 3).
Experiments were made in order to evaluate amount of burnable hydrogen – air mixture (above the lower flammability limit) in free turbulent jet at different pressures.
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What phenomena were studied
| Effects of initial pressure and nozzle size on hydrogen distribution and flow velocity in free turbulent jet.
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What phenomena / effects can be studied
| Effects of initial pressure and nozzle diameter on turbulent jet behavior can be validated. Axial and transverse hydrogen distribution in free turbulent jet can be validated. Evolution of the flow velocity in free jet can be validated.
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Instrumentation
| High pressure gas system with pressure and flow rate control used high speed valves and Prandtl pitot tubes and Coriolis sensor for mass flow control. 2D positioning measurement system 2x2.5 m based on ultrasonic sensors of hydrogen concentration. Ultrasonic hydrogen sensor has 10 cm spatial resolution. Accuracy of the method is ± 0.1 %.
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Test variables
| Initial pressure 20 – 260 bar
Nozzle diameter 0.16 – 1 mm
Hydrogen mass flow rate 0.2 – 8 g/sec
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Data description / Data completeness
| All concentration profiles and flow velocity data are in digital format.
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Data availability
| Restricted currently.
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Source of data / Reference
| Contract report BM 3444044, 2005
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Why were chosen
| No similar results elsewhere are available
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Relevance to the project purposes
| Hydrogen release from pressurized vessel. Dynamic hydrogen concentrations and flow velocity profiles are valuable for experimental validation of numerical models of hydrogen free jets. Flammability of the turbulent hydrogen jet.
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Experimental data
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Results of simulations
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