ISO 19030-1:2016 pdf free

ISO 19030-1:2016 pdf free.Ships and marine technology一Measurement of changes in hull and propeller performance
Variations in the delivered power required to move the ship through water at a given speed, and the same environmental conditions and operational profile, are due to changes in the underwater hull resistance and/or propeller efficiency. Changes in underwater hull resistance are due to alterations in the condition of the hull. Changes in the propeller efficiency are due to both alterations in the condition of the propeller and to modifications to the flow of water to the propeller (the hull wake) as consequence of alterations to the hull condition.
For a vessel in service, both environmental conditions and operational profile (e.g. speed, loading, trim) vary. In order to measure changes in the speed-power relationship for a vessel in service, it is necessary to compare two periods (a reference period and an evaluation period) where the environmental conditions and the operational profile are adequately comparable (filter the observed data) and/or apply corrections (normalize the observed data).
There are a number of alternative procedures for filtering and normalizing observed data. These procedures each have advantages and disadvantages in terms of the resulting accuracy of the measurements. This document prescribes a practical blend of filtering and normalization procedures found to yield sufficient accuracy.
NOTE The relative importance of the different resistance components varies to certain degree with the operational and environmental condition the vessel is exposed to. Also, the accuracy of the models to correct/normalize for such variations depends on the operational and environmental conditions. These dependencies impact the accuracy of the hull and propeller performance indicators as described in the current standard. Therefore, in the estimation of the accuracy of the performance indicators and for the intended use comparable operational and environmental conditions over the reference and evaluation period (see Annex A) are assumed. Future revisions of this document will re-evaluate if more accurate correction formulae are available that take the above mentioned dependencies into consideration.
Hull and propeller maintenance, repair and retrofit activities have an effect on the energy efficiency of a ship in service. An indication of these effects can be obtained by measurement of changes in the delivered power required to move the ship through water at a given speed between two periods for which the environmental conditions and operational profiles have been made adequately comparable through filtering and/or normalization of the observed data. ISO 19030-1 pdf free.