Research Of The Ship CCHP System Based On Internal Combustion Engine

As we all know, the situation that global energy is in short supply becomes more and more intensified. The earth’s environmental problems are highlighted because of the long-term dependency and over-exploitation of fossil energy. These bring many challenges to the world shipping industry.So, the new generation of CCHP system characterized of fuel diversification, equipment Miniaturization, intelligence and environment-friendly is one of the technological trends of the thermodynamic systems in the future ship. This paper works on the scheme-designing of ship CCHP system based on the internal combustion engine and its performance analysis of a ro-ro passenger ship. Firstly, adopting the calculation method of demand coefficient, it calculates the power load; it calculates the cooling load using the index method. And according to CBT3373-91 Standard, it calculates the ship heating load including oil tanks heating and cabins heating in winter. Then, on the principle of energy cascade utilization,2 sets of ship CCHP systems based on the internal combustion engine are designed. Together with the original scheme, it accomplishes technical economic and thermal economic analysis of the 3 sets of system solutions at design conditions. Finally, in order to comprehensively evaluate the pros and cons of the three system schemes, it establishes the analytic hierarchy process model with 11 indicators such as economy and so on. And through the calculation of weightiness with the program compiled by matlab, and the scheme 2 is finally indentified to be the optimal system of comprehensive performance.Because of changes in load and atmospheric conditions, in most cases, the ship CCHP systems and its equipments are running in non-design conditions, and the analysis of the off-design performance of them is of great practical value. Based on the off-design analysis formula of the constant speed internal combustion engines, analytical off-design Performances of HRSG and the heat balance equation of oil-fired boilers, combined with the Gordon-NG model of Lithium bromide absorption refrigeration unit, the cogeneration system model had been established. By this model, the off-design performance in maritime navigation and loading and unloading conditions of project 1 and project 2 on a typical day in winter and summer is made a comparative analysis thoroughly. The results indicate that performance of project 2 is apparently superior to project 1’s at off-design point.