ISO 5164:2014 石油製品—モーター燃料のノック特性の決定—調査方法 | ページ 6

3.1

accepted reference value

ARV

value that serves as an agreed-upon reference for comparison, and which is derived as: a theoretical or established value, based on scientific principles, an assigned or certified value, based on experimental work of some national or international organization, or a consensus or certified value, based on collaborative experimental work under the auspices of a scientific or engineering group

3.2

check fuel

fuel of selected characteristics that has a RON accepted reference value determined by round-robin testing by multiple engines in different locations

3.3

cylinder height

relative vertical position of the CFR engine cylinder with respect to the piston at top dead center (t.d.c.) or the top machined surface of the crankcase

3.4

dial indicator reading

numerical indication of cylinder height, indexed to a basic setting when the engine is motored with the compression ratio set to produce a specified compression pressure

Note 1 to entry: The dial indicator reading is expressed in thousandths of an inch.

3.5

digital counter reading

numerical indication of cylinder height, indexed to a basic setting when the engine is motored with the compression ratio set to produce a specified compression pressure

3.6

detonation meter

knock signal conditioning instrumentation that accepts the electrical signal from the detonation pickup and produces an output signal for display

Note 1 to entry: The meter is either analogue or digital.

3.7

detonation pickup

magnetostrictive-type transducer that threads into the engine cylinder to sense combustion-chamber pressure and provide an electrical signal proportional to the rate-of-change of that cylinder pressure

3.8

firing

engine operation with fuel and ignition

3.9

fuel-air ratio for maximum knock intensity

proportion of fuel to air that produces the highest knock intensity for each fuel

3.10

guide table

tabulation of the specific relationship between cylinder height and octane number for the CFR engine operated at standard knock intensity and a specified barometric pressure

3.11

knock

abnormal combustion, often producing an audible sound, caused by auto-ignition of the air-fuel mixture

3.12

knock intensity

measure of engine knock

3.13

knockmeter

indicating meter with a division scale that displays the knock intensity signal from the detonation meter

Note 1 to entry: The meter is either analogue or digital.

3.14

motoring

engine operation without fuel and with the ignition shut off

3.15

research octane number

RON

numerical rating of knock resistance for a fuel obtained by comparing its knock intensity with that of primary reference fuels of known research octane number when tested in a standardized CFR engine operating under conditions specified in this document

3.16

oxygenate

oxygen-containing organic compound, such as various alcohols or ethers, used as a fuel or fuel supplement

3.17

primary reference fuel

PRF

2,2,4-trimethylpentane (iso-octane), n-heptane, volumetrically proportioned mixtures of iso-octane with n-heptane, or blends of tetraethyl lead in iso-octane, which define the octane number scale

3.18

spread

sensitivity of the detonation meter expressed in knockmeter divisions per octane number

3.19

toluene standardization fuel

TSF

volumetrically proportioned blend that has RON accepted reference value and specified rating tolerances