VH2D-DataAnalysis

Vented Hydrogen Deflagration Data Analysis

Raw Campaign Loading

Use the main MATLAB function once to generate/rebuild the cached .mat file:

campaigns = MainFcn_Load_VH2D_RawCampaign_001("VH2D_Wk22", ["02","03","04"]);

The default stream layout currently expected by the loader is:

streamSpecs = struct( ...
    'id',                     {"DAQ-1", "DAQ-2-3", "DAQ-4", "H2BGA", "HS-D2", "HS-D3"}, ...
    'folder',                 {"DAQ-1", "DAQ-2-3", "DAQ-4", "H2BGA", "H2S",   "H2S"}, ...
    'pattern',                {"*.tpc5","*.mf4",   "*.mf4", "*.csv", "*-D2.txt", "*-D3.txt"}, ...
    'format',                 {"tpc5",  "mf4",     "mf4",   "csv",  "h2txt",    "h2txt"}, ...
    'outputPath',             {"DAQ_1", "DAQ_2_3", "DAQ_4", "H2BGA","HS.D_2",   "HS.D_3"}, ...
    'requiredChannelPattern', {"",      "",        "",      "conc", "",         ""});

This means DAQ-2-3 is still loaded as one combined stream. If a future campaign separates DAQ-2 and DAQ-3, pass a custom StreamSpecs at the function call instead of changing the loader internals.

Abbreviations: H2BGA means Hydrogen Binary Gas Analyser measurements, and HS means Hydrogen Sensors.

The function is located at:

3-Calculations-Files/Matlab-Files/Main_Functions/EMP2X-Project/MainFcn_Load_VH2D_RawCampaign_001.m

For normal analysis, load the cached .mat file directly because it is faster:

load("2-Data/ConvertedData/VH2D-Wk22/VH2D_Wk22_Groups_02_03_04.mat")

Each campaign cache is saved separately in:

2-Data/ConvertedData/<campaign-folder>/<campaign-name>_Groups_<groups>.mat

The cached .mat file stores the campaign and cache metadata using campaign-specific variable names, not generic campaigns or cacheInfo variables. For example, loading:

load("2-Data/ConvertedData/VH2D-Wk22/VH2D_Wk22_Groups_02_03_04.mat")

creates:

VH2D_Wk22
VH2D_Wk22_cacheInfo

This avoids overwriting existing workspace variables named campaigns or cacheInfo.

Older cache files that still contain generic campaigns or cacheInfo variables are migrated automatically the next time they are loaded through MainFcn_Load_VH2D_RawCampaign_001.

Basic extraction example:

campaign = VH2D_Wk22;
group = campaign.groups.Group_02;
run = group.runs.VH2D_Wk22_02_01;

t = run.DAQ_1.t;
y = run.DAQ_1.signal(:,1);
plot(t, y);

Unit Conversion Layer

Raw loaded data is not modified. Unit conversion is handled by a dedicated auxiliary function:

converted = AuxFcn_ConvertVH2DUnits_001(VH2D_Wk22);

Details are documented in:

3-Calculations-Files/Matlab-Files/Auxilliary_Functions/EMP2X-Project/README_AuxFcn_ConvertVH2DUnits_001.md

Time-Vector Alignment Layer

After unit conversion, build a separate trigger-aligned layer:

aligned = AuxFcn_AlignVH2DTimeVectors_001(converted, ...
    TriggerThreshold_V=4, ...
    ReferenceStreams="DAQ_1", ...
    AlignStreams=["DAQ_2_3","DAQ_4"]);

Details are documented in:

3-Calculations-Files/Matlab-Files/Auxilliary_Functions/EMP2X-Project/README_AuxFcn_AlignVH2DTimeVectors_001.md

Pressure DC-Offset Removal Layer

After alignment, remove pressure-channel background offset in a separate layer:

offsetCorrected = AuxFcn_RemoveVH2DPressureOffset_001(aligned, ...
    BaselineWindow_s=[-0.050, -0.005]);

This is applied only to pressure channels in kPa; trigger and concentration channels are copied unchanged. Details are documented in:

3-Calculations-Files/Matlab-Files/Auxilliary_Functions/EMP2X-Project/README_AuxFcn_RemoveVH2DPressureOffset_001.md

Pressure/Trigger Initial Crop Layer

After pressure offset removal, create a pressure-preprocessed layer by cropping only the DAQ pressure/trigger streams:

pressurePreprocessed = AuxFcn_CropVH2DPressureTriggerSignals_001( ...
    offsetCorrected, ...
    CropWindow_s=[-0.050, Inf], ...
    StreamFields=["DAQ_1","DAQ_2_3","DAQ_4"]);

The full campaign structure is preserved. H2BGA and HS concentration streams are copied unchanged and will be handled later in a dedicated concentration preprocessing layer. Details are documented in:

3-Calculations-Files/Matlab-Files/Auxilliary_Functions/EMP2X-Project/README_AuxFcn_CropVH2DPressureTriggerSignals_001.md

More extraction examples are documented in:

3-Calculations-Files/Matlab-Files/Main_Functions/EMP2X-Project/README_MainFcn_Load_VH2D_RawCampaign_001.md

Campaign metadata JSON files are stored in:

2-Data/RawData/VH2D-Wk22/Metadata

Use AuxFcn_LoadVH2DMetadata_001 to read the full JSON metadata, then use AuxFcn_BuildVH2DRawReportTables_001 to display small report-friendly tables. The complete metadata remains available internally, but the DPP should show focused summaries such as raw load status, run plan, gas mixing, DAQ systems, sensor mapping, and group notes.