ISO INTERNATIONAL STANDARD 8178-4 Fourth edition 2020-06 Reciprocating internal combustion engines Exhaust emission measurement - Part 4: Steady-state and transient test cycles for different engine applications Moteurs alternatifs a combustion interne - Mesurage des émissions de gaz d'échappement - Partie 4: Cycles d'essai a I'état stable et transitoires pour differentes applications des moteurs Reference number IS0 8178-4:2020(E) @ IS0 2020 IS0 8178-4:2020(E) COPYRIGHT PROTECTED DOCUMENT @ IS0 2020 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting below orIso's memberbodyin the country ofthe requester ISO copyright office CP 401 · Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 0111 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2020 - All rights reserved IS0 8178-4:2020(E) Contents Page Foreword ..vi Introduction ..vii 1 Scope. 2 Normative references 3 Terms and definitions ..1 4 Symbols and abbreviated terms .11 4.1 General symbols. .11 4.2 Symbols and abbreviated terms for fuel composition ..13 4.3 Symbols and abbreviated terms for chemical components .14 4.4 Abbreviated terms... ..14 5 Test conditions .15 5.1 Engine test conditions. .15 5.1.1 Laboratory test conditions .15 5.1.2 Test validity .16 5.2 Engine power .16 5.2.1 Auxiliaries to be fitted ..16 5.2.2 Auxiliaries to be removed ..16 5.2.3 Determination of auxiliary power .17 5.2.4 Engine cycle work. .17 5.3 Engine intake air ..17 5.3.1 General. ..17 5.3.2 Intake air restriction. .17 5.3.3 Engines with charge air cooling .18 5.4 Engine exhaust system. .18 5.4.1 General. ..18 5.4.2 Exhaust restriction. .18 5.4.3 Engine with exhaust after-treatment system .18 5.5 Specific test conditions .19 5.5.1 Engine with exhaust after-treatment system 19 5.5.2 Crankcase emissions.. .22 5.6 Cooling system ..23 5.7 Lubricating oil. .23 6 Test fuels ..23 7 Test cycles 24 7.1 General. 24 7.2 Test speeds .24 7.2.1 Maximum test speed (MTS) 24 7.2.2 Rated speed. 25 7.2.3 Intermediate speed. 25 7.2.4 Idle speed. .26 7.2.5 Test speed for constant-speed engines .26 7.3 Torque and power. 27 7.3.1 Torque. .27 7.3.2 Power. 28 7.4 Engine mapping 28 7.4.1 Engine mapping for transient cycles. 29 7.4.2 Engine mapping for variable-speed steady-state cycles. .30 7.4.3 Engine mapping for constant-speed engines. .30 7.5 Steady-state test cycles .31 7.5.1 Discrete mode test cycles .31 7.5.2 Ramped-modal test cycles .33 7.5.3 Cycle types and applicability .33 @ IS0 2020 - All rights reserved iii IS0 8178-4:2020(E) 7.6 Transient cycles. 37 7.6.1 General. 37 7.6.2 Non-road transient cycle (NRTC) .37 7.6.3 Large spark-ignition non-road transient cycle .38 7.7 Test cycle generation .38 7.7.1 Generation of steady-state discrete-mode or RMC test cycles .38 7.7.2 Generation of NRTC and LSI-NRTC .39 8 Test run. 41 8.1 General test sequence. 41 8.2 Instrument validation for test.. 44 8.2.1 Validation of proportional flow control for batch sampling and minimum dilution ratio for PM batch sampling. 44 8.2.2 Gas analyser range validation, drift validation and drift correction. 45 8.2.3 PM sampling media (e.g. filters) preconditioning and tare weighing 45 8.3 Sample system decontamination and preconditioning 47 8.3.1 Verification of HC contamination. 48 8.4 Pre-test procedures. 49 8.4.1 Preparation of the sampling filters 49 8.4.2 General requirements for preconditioning the sampling system and the engine 49 8.4.3 Engine cool down (NRTC) 50 8.4.4 Preparation of measurement equipment for sampling 50 8.4.5 Calibration of gas analysers. 51 8.4.6 Adjustment of the dilution system 51 8.5 Engine starting and restarting 51 8.5.1 Engine start 51 8.5.2 Engine stalling. 51 8.6 Test cycle running procedure. .52 8.6.1 Test sequence for discrete steady-state test cycles 52 8.6