الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
This thesis is concerned with studying the effect of the main environmental conditions and the operational patterns on the performance of marine Diesel propulsion system. The propulsion system is defined by its three subsystems; hull, Diesel engine(s) and propeller(s). The study starts with reviewing the relevant literature .
. This literature revealed the need for additional work in the area of rationally quantifying sea margin, which takes account of the effect of the environment as well as the operational pattern on the performance of the propulsion system.
The different parameters affecting Diesel engine performance are investigated. The engine-propeller matching procedure is examined considering the optimum selection of the power required to propel the ship in a seaway. The added resistance due to sea state is calculated for a family of wave spectra, which represents the seaway more realistically. The calculated added resistance for different sea states was statistically analysed. The analysis revealed that the added resistance is normally distributed, and accordingly the sea margin would follow the same distribution. This approach makes it possible to estimate, rationally, the required engine power during the early stages of ship design considering the effect of the environmental conditions and the projected operational patterns.
Since the ship’s speed is a robabilistic quantity, be described by its statistical parameters, i.e., th and the variance. Therefore, a method is derived td the mean and variance of ship’s speed. This methodl the variability of ship’s speed together with its meanl a ship propelled with a given power on a specified trade which enables the ship designer and/or operator tol the profitability of the ship in an early stage of I The problem of selecting the optimum engine power is very an economical one. Therefore, the probability density of the number of trips achieved per year for a trade route is derived, taking into account the effect of the random change of port time coefficient and the loading coefficient. The effect of the operational pattern on the performance of the propulsion system could easily be assessed by this statistical approach
The proposed method is validated by a case study. The method proved to be a successful design tool that enables decision makers, like naval architects to select the optimum value of the equired sea margin. Also, the proposed method could be used by the ship owners and or ship operators to assess the economics of the ship for different projected patterns of operation.