Considering the experimental results, the following conclusions were derived about the PM emission during voyage and the measuring procedure.
(1) Measurement of the PM emission using the partial flow dilution tunnel can be applied on board.
(2) The higher the engine load is, the more PM (g/kWh) are emitted both with the propeller and the generator characteristics.
(3) Percentage of SOF (soluble organic fraction) in the PM emission is about 70% in case of the 2-cycle marine diesel engine of the experimental ship.
(4) Adopting the best combination of the dilution ratio and the minimum filter loading, PM measuring time can be saved keeping the accuracy of the data.
The authors wish to thank HORIBA, Ltd. for their kind cooperation. The authors also appreciate the support of the staff and students of National Fisheries University and training ship "Koyo Main".
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