الفهرس 
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Abstract
Fresh water is not distributed evenly throughout the planet and it is not available in sufficient quantities either when or where it is needed. United Nations estimates that by 2050 more than two billion people in 48 countries will lack sufficient water due to the tremendous growing in the world’s population. This crisis is more severe in case of vessels where water sources are limited. In general, fresh water is used on shipboard especially on cruise ships for many purposes, including the pure fresh drinking water, water for the toilet systems on ships, cleaning the ship and doing laundry, the galleys, for swimming pool and even for running other important machinery which use fresh water as a cooling medium.
In this thesis, we target the fresh water generation aboard passenger ships through exploiting the waste heat energy produced either from the main engine exhaust and/or from the cooling water. This approach has several advantages, including saving the costs of buying fresh water where the savings are achieved on the long term, exploiting an already-existent resources which were wasted in current vessels, and finally saving the weight of the freshwater during the voyages where the capacity of freshwater tanks will be for one or two days not for the complete voyage duration. To this end, different methods of water desalination have been investigated with studying the mathematical model of the thermal methods and selection the suitable technique to apply on passenger ship.
Based on this study, the heat balance calculations have been applied to evaluate the quantity of heat loss from the main engine exhaust and in cooling water system, and perusal about the heat recovery system for the main engine of the passenger ships. Afterward, a Visual Basic program has been developed for applying the setting up of three water desalination units, namely Multiple Effect Evaporation, Multi Stage Flash - Once Through (MSF - OT) and multi-stage flash - Brine Circulation (MSF-BC), on passenger ships by using the waste heat energy. Finally, performance of the proposed system has been examined in terms of the expected gains.
The thesis is organized as follows. Chapter 1 provides a brief introduction about the water paucity all over the world and its impact on water price. Chapter 2 introduces the different techniques of sea water desalination in more details. Chapter 3 deals with the numerical analysis of propulsion machineries thermodynamics behavior onboard passenger ships. It shows the heat balance calculations of the main engine to value the quantities of exhaust and cooling water heat. Chapter 4 explains discuss the implementation of our Visual Basic program to empirically estimate the generated fresh water using the proposed method. Chapter 5 introduces the proposed system for free fresh water generation on shipboard, the Case study and numerical investigation. Finally, chapter 6 draws conclusions for this work and describes the future work that can enhance the performance of our work.