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SBEP 2006

SBEP(s) for years 2006 - 2007:

SBEP on hydrogen release and mixing

  • V4 FZK jet experiment
  • V5 GexCon D27
  • V6 Extended SBEP: BAM experiments with LH2

SBEP on hydrogen fires or explosions

  • V7 Shell experiments
  • V8 Tube with venting
  • V9 Extended SBEP: DDT from FhICT

Deadline for all cases 20.12.2006.


SBEP V4 (See D57, pp. 35 - 36)

Comments to the table (download documents: HD-Tab.pdf, H2jet.eps, shadow.eps. Keyword SBEP-V4. They have generic title 'Specifications of V4 Document [1,2,3]'):

Nozzle diameter, d, is internal orifice diameter
Distance from the nozzle, x, is a distance to the transverse cross-section where concentration and velocity profiles were measured (see H2jet.eps file)
Pressure, p, is a pressure measurement at the closest to the nozzle position
Mass flow rate was measured by two sensors (Prandtl and Coriolis)
Injection time is a time between opening and cut-off of the valve
Transverse concentration and velocity: YES means that we have data on [H2] and velocity distribution for steady-state regime; NO means that we only have [H2] and velocity measurements at axial jet position against time.
Shadow means that we have or not shadow pictures like that shown in the file attached (shadow.eps)
In order of priorities we recommend you four sets (shown in the table HD-Tab.pdf):
No 1: 1 mm; p = 100 bar; tests HD 31-34; tests HDH4 with shadow at 180 bar (complete data with [H2] and velocity distribution with axial time dependence of [H2] and velocity + shadow)

No 2: 0.75 mm; p = 208 bar; tests HDH3; (only data with axial time dependence of [H2] and velocity + shadow)

No 3: 0.25 mm; p = 160 bar; tests HD 22-24; tests HDH0 and HDH1 with shadow at 100 and 240 bar (complete data with [H2] and velocity distribution with axial time dependence of [H2] and velocity + 2 shadows)

No 4: 1 mm; p = 196 bar; tests HDH 13; (only data with axial time dependence of [H2] and velocity + shadow)

Data to be presented for comparison with the experiments:

  1. Concentration vs. coordinate along longitudinal horizontal axis C(z)
  2. Concentration vs. radial coordinate in horizontal plane C(r)
  3. Concentration vs. time at horizontal axes z C(t)
  4. Gas velocity vs. coordinate along longitudinal horizontal axis C(z)
  5. Gas velocity vs. radial coordinate in horizontal plane C(r)
  6. Gas velocity vs. time at horizontal axes z C(t)
  7. 'Shadow photograph' movie: it has to cover at least first half of jet (0 m < z < 1 m) and time period (0 s < t < 8 s). These data correspond to the experimental ones.

SBEP V5 (See WP3.1_v0.1.doc Benchmarks for evaluation of CFD codes)

SBEP V6 (no information; for liquid H2 NCSRD is responsible)

It is extended SBEP, i.e. it is optional.

SBEP V7 (See D57, pp. 33 - 34)

Download documents:

  1. HSL Casestudy 1.doc - provided by Stefan Ledin;
  2. Figs 3,4,9.ZIP - provided by Les Shirvill.

Keyword SBEP-V4. They have generic title 'Specifications of V7 Document [1,2]')

Here I just repeat the comments made for HyApproval partners. They are mostly useless for V7 (since V7 is pre-mixed case), but can be, probably, later used by reviewers of HyApproval project.
It was also mentioned during one of our meetings that calculation of jet release experiment (as one of future SBEP) can be extremly interesting.

1. you remember that experimental conditions in Shell tests were:

 - source 600 g during 0.7 s, temperature -20C at nozzle by 35 MPa.

I think that it would be reasonable to make simulations which can be compared with experimental ones with the aim to increase the credibility of such simulations.

Therefore, I think if one is going to make simulation of mitigated scenario, he/she has to start with this test.

During the discussion at last meeting it was mentioned, that source with 100 g/s is much more realistic than 600 g / 0.7 s. Therefore, I think that for other cases (mitigated 700 bar and non-mitigated 350, 700 bar) it is better to take

 - source 100 g/s, temperature at nozzle -20C by 70 MPa (non-mitigated)
 - source 100 g/s, temperature at nozzle -20C by 35 MPa (non-mitigated)
 - source 100 g/s, 2 s, temperature at nozzle -20C by 70 MPa (mitigated).

Time of 2 sec for isolation was specified in Table 4.2 (Leak source data).

2. Thanks to Les we now have understand the layout for RS and transducer locations.

In the attached document you will find Figures 3, 4 and 9.

Figures 3 and 4 are the layout and sensor locations for premixed experiments (they coincide with those provided to HySafe).

Actually, as I understood, layout for jet release experiments was slightly different (e.g., dispenser was 10 cm shifted), but the exact data are not available. I agree with Les proposal to use the same layout for both type of tests.

Thus, Figure 3 and 9 are the layout and sensor locations for jet release experiments (Figure 9 coincide with data provided to HyApproval).

SBEP V8 (See D57, pp. 46 - 47)

Initial conditions: pressure P = 1.01e5, temperature T = 290 K, concentration 13% H2 in air.

Obstacle blockage ratio (BR) = 60% (BR = 1 - (r/R)^2) here r - orifice radius; R - tube internal radius

Vent ratio = (r/R)^2 here r - radius of opening in the flange, which was covered by the 1 m (micron) plastic foil; R - tube internal radius

  1. set (to be simulated) Ignition point x = 0; vent ratio = 0%, 25%, 40%, 100%
  2. set (optional) Vent ratio = 40%, Ignition point = 0 m, 0.7 m, 6.47 m

Remark on foil influence:
During experiments the differential pressure, which can remove the foil, was measured. It was at the level of 5 mbar. Thus, we believe that the influence of the foil on hydro-dynamics can be neglected.

As a comment from GexCon (OR Hansen) we believe the foil may be of some importance, but mainly for the initial flame development for the more open cases 40% and 100% cases. We thus expect that the flame acceleration will be faster for these cases due to the foil (simulations we did indicated that).

SBEP V9 (See D57, pp. 5, 6)

It is extended SBEP, i.e. it is optional.

Experiments IA1-IA5. Additional information can be obtained directly from Helmut Schneider.

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