6.4.3 Engine performance measurements
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - NOx Technical Code (2008) - Technical Code on Control of Emission of Nitrogen Oxides from Marine Diesel Engines - Chapter 6 - Procedures for demonstrating compliance with NOx emission limits on board - 6.4 Direct measurement and monitoring method - 6.4.3 Engine performance measurements

6.4.3 Engine performance measurements

  6.4.3.1 Table 7 lists the engine performance parameters that shall be measured, or calculated, and recorded at each mode point during onboard NOx monitoring.

Table 7 - Engine parameters to be measured and recorded

Symbol Parameter Dimension
n d Engine speed min-1
p C Charge air pressure at receiver kPa
P Brake power (as specified below) kW
P aux Auxiliary power (if relevant) kW
T sc Charge air temperature at receiver (if applicable) K
T caclin Charge air cooler, coolant inlet temperature (if applicable) oC
T caclout Charge air cooler, coolant outlet temperature (if applicable) oC
T Sea Seawater temperature (if applicable) oC
qm f Fuel oil flow (as specified below) kg/h

  6.4.3.2 Other engine settings necessary to define engine-operating conditions, e.g., waste-gate, charge air bypass, turbocharger status, shall be determined and recorded.

  6.4.3.3 The settings and operating conditions of any NOx reducing devices shall be determined and recorded.

  6.4.3.4 If it is difficult to measure power directly, uncorrected brake power may be estimated by any other means as approved by the Administration. Possible methods to determine brake power include, but are not limited to:

  • .1 indirect measurement in accordance with 6.3.3; or

  • .2 by estimation from nomographs.

  6.4.3.5 The fuel oil flow (actual consumption rate) shall be determined by:

  • .1 direct measurement; or

  • .2 test-bed data in accordance with 6.3.1.4

Parent topic: 6.4 Direct measurement and monitoring method
Copyright 2022 Clasifications Register Group Limited, International Maritime Organization, International Labour Organization or Maritime and Coastguard Agency. All rights reserved. Clasifications Register Group Limited, its affiliates and subsidiaries and their respective officers, employees or agents are, individually and collectively, referred to in this clause as 'Clasifications Register'. Clasifications Register assumes no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant Clasifications Register entity for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract.