Introducing pre-cooling air conditioning system for vessel operating in high ambient temperatures.

This project aims at saving upgrading cost and avoid vessel downtime by maintain existing HVAC system with help of new pre cooling system which consisting of a chiller unit, air handling unit, chilled water pump and chilled water piping with instruments. The current HVAC system was designed for 32 °C ambient condition and capable to handle 40% of fresh air. Vessel has committed for a project in middle east where the ambient temperature of 45 °C (Persian Gulf). Due to increase in ambient temperature, performance of air handling units will be affected which could bring the indoor temperature to unacceptable level. However, the new pre cooling system will be designed for 45 °C and capable to feed fresh air to all the current air handling units after alter the fresh air properties to desired condition. Thus, it will result in current air handling unit’s performance improvement and retain indoor space temperature in acceptable limit. The main aim is to select the pre cooling air handling unit, chiller unit, chiller pump, chiller pipe and instruments with necessary design layouts to conserve upgrading cost, avoid major works and vessel downtime. It’s necessary to make detailed calculations and design layouts to select each component of the pre cooling system. All calculations will be made according to International Organization for Standardization – (hereafter abbreviated ISO), American Society of Heating, Refrigerating and Air Conditioning Engineers – (hereafter abbreviated ASHRAE) and other shipping classification societies (American bureau of shipping - ABS, Det Norske Veritas - DNV, Bureau Veritas - BV, Lloyd's Register - LR, Registro Italiano - RINA). A literature review will be carried out to explore calculation methods, components selections, design layouts and other key values which will be used in calculations. Finally, a simplified independent air conditioning system is proposed as pre cooling system to supply pre cooled fresh air to all the current air handling units of the current HVAC system. The proposed pre cooling air handling unit can be connected to fresh air intakes of current air handling unit’s through independent duct works which will be designed to carry required amount of fresh air for all the current air handling units. Calculation will be carried out to ensure duct sizing all calculations, layouts and selections which are developed throughout this thesis will be verified against standards.