TSI Instruments SIZER EEPS 3090, Руководство по эксплуатации и обслуживанию

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5-10 Model 3090/3090AK Engine Exhaust Particle Sizer
TM
Spectrometer
U s i n g a n A l t e r n a t i v e I n v e r s i o n M a t r i x
Chapter 3 describes how to select an alternate matrix to upload to the
instrument before starting a new run. You may also select a different matrix
to apply to the raw data in an existing file.
Note : If you have a data file which does not contain the raw data values
this option is not available. The data file must have been created
using EEPS Firmware version 3.05 or later and EEPS Software
version 3.1.0 or later.
Open the Run|Properties dialog for an existing data file. You may select a
different matrix to apply to your raw data set using the combo box in the
Instrument Matrix section. Select the Apply button to recalculate the
number concentration values. The data in the graphs and tables will
update. You may then save your file as a different file name or overwrite
the file with these changes when you close the file.
The data inversion in the Model 3090 uses a matrix to convert the
measured electrometer currents to size and concentration data. The
DEFAULT matrix is based upon a combination of theoretical and
experimental data. However, variation in particle shape can affect how the
particles are charged within a unipolar charger which affects how they are
sized. In general, agglomerates acquire a higher net charge than compact,
near spherical particles.
To address differences in charging characteristics, two additional particle
morphology-specific inversion matrices are included within EEPS software
that result in better correlation between EEPS spectrometer and SMPS
spectrometer data. Both matrices were developed by empirically calibrating
the EEPS spectrometer to SMPS spectrometer measurements.
SOOT.matrix is designed to specifically change how soot particles,
typically chain aggregates, in the accumulation mode (~>100nm) are sized.
When measuring engine emissions (from constant volume sampling (CVS)
tunnel or directly from the exhaust using partial flow dilution) it is
recommended that the soot matrix be used.
COMPACT.matrix is designed to be used when measuring aerosols
composed of compact, nearly spherical, particles. The compact matrix is
useful for laboratory studies in which it is known (or assumed) that the
sample aerosol is composed of compact particles such as atomized oil
droplets, salt solution residue, or polystyrene latex spheres (PSL).