ISO/TS 19713-2:2010 道路車両—内燃エンジンおよびコンプレッサー用の吸気洗浄装置—パート2：粗い粒子（光学直径5 µm〜40 µm）を使用したフラクショナル効率テスト | ページ 6

3.1

air cleaner assembly

assembly which includes the air cleaner housing and the air filter element

3.1.1

single-stage air cleaner

air cleaner which does not incorporate a separate pre-cleaner

3.1.2

multistage air cleaner

air cleaner consisting of two or more stages, the first usually being a pre-cleaner, followed by one or more filter elements

Note 1 to entry: If two elements are used, the first is called the primary element and the second is called the secondary element.

3.1.3

pre-cleaner

device usually using inertial or centrifugal means to remove a portion of the test dust before reaching the filter element

3.2

air filter element

actual filter supported and sealed within the air cleaner assembly

3.3

test airflow rate

measure of the volume of air passing through the test duct per unit time

Note 1 to entry: The test airflow rate is expressed in cubic metres per second.

3.4

pressure loss

permanent pressure reduction due to a decrease in the flow energy (velocity head) caused by the filter (Pa at standard conditions of 20 °C and 101,3 kPa)

3.5

fractional efficiency

E_{f, i}

ability of the air filter to remove particles of a specified size expressed as a percentage for particle size i

(1)

where

C1, i	is the number of particles per unit volume of specified size, i , upstream;
C2, i	is the number of particles per unit volume of specified size, i , downstream

Note 1 to entry: Fractional efficiency is expressed in percent.

3.6

fractional efficiency before dust loading

efficiency before the collected particles have any measurable effect on the efficiency of the filter under test

Note 1 to entry: The collected particles can affect the measured filter efficiency before enough aerosol is collected to have any measurable effect on the filter pressure loss.

3.7

incremental fractional efficiency

efficiency, determined at the specified flow rate as a function of particle size at 10 %, 25 %, 50 % and 100 % of filter life, which is determined by pressure loss across the filter as the filter is loaded with ISO 12103-1 test dust

Note 2 to entry: If necessary, the requester and the tester can agree upon different criteria for incremental fractional efficiency.

3.8

fractional penetration

P_{f, i}

Note 1 to entry: Fractional penetration is expressed in percent.

3.9

test dust loading

mass of test dust collected by the air cleaner assembly or air filter element at a specified flow rate expressed in grams

3.10

particle measurement device

aerosol spectrometer

instrument for sizing, or counting, or sizing and counting, aerosol particles

Note 1 to entry: Recommended particle counters are optical particle counters (OPC) or other counters demonstrating good correlation in measuring particle sizes, e.g. aerodynamic particle counters (APC).

3.11

test aerosol

particles suspended in air, used for filter efficiency evaluation or dust loading

3.11.1

fractional efficiency test aerosol

aerosol used to measure the efficiency of the test filter, the concentration of which is low enough to prevent coincidence-related errors in the particle counters, and does not change the filter efficiency due to loading

Note 1 to entry: The aerosol charge is reduced so that it approximates a Boltzman equilibrium charge distribution. The requirements for the efficiency challenge aerosol are given in 4.2.10 and 4.2.11.

3.11.2

loading test aerosol

aerosol used to load the filter, the concentration of which is high enough to allow loading of the filter in a reasonable amount of time

Note 1 to entry: The requirements for the loading test aerosol are given in 4.2.13.2.

3.12

correlation ratio

R

ratio of the number of particles observed at the downstream sampling location to the number of particles at the upstream sampling location when no filter is installed in the test system

Note 1 to entry: This number can be greater or less than 1.

Note 2 to entry: The method of calculating the correlation ratio is given in Annex B.

3.13

log mean diameter

D_{l, i}

weighted mean diameter calculated by

(4)

where

Di	is the lower threshold of particle size range;
Di +1	is the upper threshold of particle size range

3.14

geometric (volume equivalent) diameter

D_{g, i}

diameter of a sphere with the same volume as the particle being measured

Note 1 to entry: For a spherical particle, it is the diameter of the sphere.

3.15

optical (equivalent) diameter

D_{o, i}

diameter of a particle of the type used to calibrate an optical sizing instrument that scatters the same amount of light as the particle being measured

Note 1 to entry: Optical diameter depends on the instrument, the type of particle used to calibrate the instrument (usually polystyrene latex spheres), the optical properties of the particle being measured, and the size of the particle.

3.16

aerodynamic (equivalent) diameter

D_ae

diameter of a sphere of density 1 g/cm³ with the same terminal velocity as the particle being measured, due to gravitational force in calm air

Note 1 to entry: The aerodynamic diameter will be used to report results to avoid different diameter measures due to different sizing and counting techniques.

Note 2 to entry: Annex F provides additional information about aerodynamic diameter.

3.17

high efficiency particulate air

HEPA

filter having 99,95 % efficiency at most penetrating particle size (class H13 in accordance with EN 1822), or 99,97 % (or higher) fractional efficiency at 0,3 µm using DOP aerosol as defined by IEST RP-CC001 recommended practice

3.18

neutralization

aerosol whose charge distribution is reduced until it provides a Boltzman equilibrium charge distribution