ISO 21441:2019 pdf download

ISO 21441:2019 pdf download.Road vehicles — Engine EGR cooler — Heat dissipation test methods
1 Scope
This document defines the methodology for the measurement of heat dissipation and pressure loss of liquid cooled engine EGR coolers in internal combustion engines for road vehicles. The principles of this document are valid for clean and fouled EGR coolers.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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3.1 EGR
technology that recirculates a portion of an engine’s exhaust gas back into the intake to control the concentration of oxygen taken into the engine
3.2 EGR gas
gas that has been extracted from the exhaust gas and is passed through the EGR cooler (3.5) core (3.14)
3.3 test gas
pressurized air or exhaust gas made by burners used in place of real EGR gas (3.2) during the heat dissipation performance test and when measuring EGR gas pressure loss (3.10)
3.4 cooling liquid
water or coolant mixture during the heat dissipation performance test and when measuring cooling liquid pressure loss (3.11)
3.5 EGR cooler
liquid cooled heat exchanger for cooling the EGR gas (3.2)
3.6 EGR gas heat dissipation amount
amount of heat lost by the test gas (3.3) during the heat dissipation performance test
Note 1 to entry: The EGR gas heat dissipation amount is expressed in kilowatts (kW).
6.2.1 Flow rate measurement
Flow rate measurement shall be carried out as follows.
a) The test gas mass flow rate shall be measured after confirming that the test gas has reached a stable state of flow.
b) The cooling liquid mass flow rate shall be measured after confirming that the cooling liquid has reached a stable state of flow.
c) The flow rate measurement shall be preferably carried out by means of mass flow meters. Otherwise, if a volumetric flow meter is used, measure the test gas and cooling liquid temperature and pressure at the vicinity of the flow meter in order to calculate the mass flow rate.
6.2.2 Temperature measurement
Temperature measurement shall be carried out as follows.
a) When measuring the test gas temperature of the inlet and the outlet, the measurement position shall be selected so as not to affect the pressure measurement taken and the temperature sensor is placed where it can control the target of the inlet temperature. One or more sensors can be used, but at least two measurement positions at same cross section are recommended.
b) When measuring the cooling liquid temperature of the inlet and the outlet, the measurement position shall be selected so as not to affect the pressure measurement taken and the temperature sensor is placed where it can control the target of the inlet temperature. One or more sensors can be used, but at least two measurement positions at same cross section are recommended.