Research On The Application Of Water Management System Of Closed Cycle Diesel

The Closed Cycle Diesel (CCD) system is a typical design solution for Air Independent Propulsion (AIP). As a crucial component of CCD, water management system (WMS) provides not only an apparatus for taking inboard and discharging outboard seawater, but also a method of transferring liquid between regions of a high and a low pressure with minimum energy expenditure. For further development of deep sea, the CCD system integrated with WMS will have extensive application perspectives for military submarines as well as civil researches or working submarines. According to the working principles, constructions and operating characteristics of CCD and WMS, the following works are completed and conclusions are explained.1. After proposing a practical research plan of CCD system, a self-contained CCD system test rig employing a standard diesel engine type 4102BG was built, which comprises of a carbon dioxide absorber and a prototype WMS. For the closed cycle of diesel engine, the mixing chamber, control strategies and algorithms of oxygen supply are designed, and a closed cycle running was carried out without load.2. Based upon mathematical models, simulation systems were established for twin vessel water management system, triple vessel water management system and six-vessel water management system. The simulative results clarified and confirmed the working principle and process of WMS.3. Applying the design idea of hydraulic cylinder for the vessel buffer structure design, using pneumatic ball valve group as the control valve, a prototype WMS with triple free piston style vessels was built firstly in China. The valve closing signals and piston location signals are fed back to PLCS (Program Logic Control System), a delay and feedback control program was determined, which is integrated with an appropriate operating sequence of vessels, and the delay time in the program can be adjusted automatically.4. In order to match the operating characteristics of vessels, and to prove the dynamic response ability as well as performance of the prototype WMS, a series of comprehensive tests were conducted in ambient pressure. The results demonstrated that the capability of the system meets the requirements of working principles of WMS. The flux and pressure characteristics were measured for the first time at home. Resulting flux stability possesses an equal performance comparing to foreign references.A test solution is presented to take the prototype WMS to operate under simulation pressure of diving depth, which involves security measures, unload means and fluid borne noise control.5. According to the quantitative analysis of energy expenses and efficiency of the prototype WMS, it was the first time that the excellent performance along with small energy expenses of the WMS was demonstrated by means of test interiorly. The power losses in the valves and in the conduits are calculated which may play important role for improvement of efficiency by further optimization of WMS design.6. Main noise sources and noise control methods for WMS were analyzed primarily, the effects of flux pulses no acoustic performance of the system was discussed. Attenuation of fluid borne noise was examined by virtually measured pressure characteristics. The results showed that, the peak value of pressure pulses resulting from continuous flux of the triple vessel WMS can be reduced 4 times approximately, and noise reduction 10 dB, compared to twin vessel WMS.