BS EN 17155:2018 pdf download

BS EN 17155:2018 pdf download.Liquid petroleum products – Determination of indicated cetane number (ICN) of middle distillate fuels – Primary reference fuels calibration method using a constant volume combustion cham ber
1 Scope
This European Standard specifies a test method for the quantitative determination of the indicated cetane number [ICN) of middle distillate fuels and blending components, intended for use in compression ignition engines. The test method utilizes a constant volume combustion chamber with direct fuel injection into heated compressed air. Calibration of the apparatus using blends of primary reference materials over a scale of 0 to 100 enables fuel ignition delays, measured from the resulting pressure increase, to be used to determine and report ICN results. This European Standard is applicable to middle distillate fuels of both petroleum and non- petroleum origin, hydrocarbon oils, oil-sands based fuels, blending components, fatty acid methyl esters (FAME), blends of fuel containing biodiesel material, diesel fuel oils containing cetane number improver additives, low-sulfur diesel fuel oils, aviation turbine fuels and polyoxymethylene dimethyl ether (OME). However, users applying this standard especially to unconventional distillate fuels are warned that the relationship between cetane number and combustion behaviour in real engines is not yet fully understood. This European Standard covers the calibrated range of 35 ICN to 85 ICN. NOTE 1 The analyser can measure ICN outside the calibrated range, but precision has not been determined. NOTE2 For the purpose of this standard, the expression“% (V/V)” is used to represent the volume fraction. WARNING一The use of this standard can involve hazardous materials, operations and equipment. This Standard does not purport to address all of the safety problems associated with its use. It is the responsibility of users of this standard to take appropriate measures to ensure the safety and health of personnel prior to application of the standard, and fulfil statutory and regulatory requirements for this purpose.
4 Principle
The indicated cetane number (ICN) of a diesel fuel is determined by comparing its ignition performance with blends of primary reference fuels of known ICN under standard operating conditions. A test portion of the material under test is automatically drawn from a sample vial located in the auto- sampler carousel, heated during pressurization, and then, at the start of a combustion cycle, a sub- portion is injected into a temperature and pressure controlled, constant volume combustion chamber, which has previously been charged with compressed air of a specified quality. Each injection, and its resulting combustion, causes a rapid pressure rise in the combustion chamber that is detected by the dynamic pressure sensor. The test sequence, using the test portion, comprises a cleaning stage and combustion cycles to obtain ignition delay (ID) values. The ICN result is determined using the mean of the combustion cycles’ IDs and the primary reference fuel (PRF) blends calibration curve. Each analyser is calibrated with seven fluids created from blends of PRFs, with known ICN calculated from Formula (1); this links test results to those obtained using EN ISO 5165 [1]. Test results outside the calibration range are determined by extrapolation using the calibration curve but are subject to increased uncertainty.