Study On Fast Filling Process Of 70MPa Shipboard Hydrogen Storage Cylinder

New energy is the trend of future development,as the most promising hydrogen energy is undoubtedly an inevitable choice,and it is very important to vigorously develop hydrogen fuel cell ship combining hydrogen energy with ships.However,during the development of hydrogen fuel cell ship,some problems will be encountered,such as high temperature and long time when filling the onboard hydrogen storage bottle.Therefore,a complete,specific and standardized hydrogenation system is established to shorten the filling time of hydrogen storage bottles.In the hydrogenation process,the rapid increase of the pressure inside the cylinder also leads to a sharp rise in temperature,which affects the mechanical properties of the carbon fiber composite layer and has a great potential safety hazard.Therefore,it is of great significance to study the fast filling process of shipboard hydrogen storage bottle in detail.The research contents are as follows:(1)Establish a complete hydrogen fuel cell ship hydrogenation system according to the specifications,and determine the main equipment such as ionic liquid compressor inlet,vortex tube,high-pressure water separator and high-pressure hydrogen storage tank;The three-stage compression system and 0.6 m3,97 MPa pressure hydrogen storage tank were determined by optimizing the process flow of hydrogenation system.The hydrogenation system is confirmed to meet the requirements of fast charging and the fast charging flow curve is obtained.(2)Through thermodynamic analysis,the main factors affecting the temperature rise of the shipboard hydrogen storage cylinder are compression effect,throttling effect,kinetic energy conversion and environmental heat transfer;The CFD model considering turbulence,heat transfer,flow and real gas effects was established and the validity of the model was verified.(3)The rapid filling process of onboard hydrogen storage cylinders was simulated numerically under different working conditions.A cyclic flow strengthening convective heat transfer was formed inside the cylinders,and the highest hydrogen flow rate appeared in the cylinder axis and outer wall area,and the top of the cylinders was in a local high temperature zone.Ambient temperature,initial pressure and precooling temperature have linear effects on the temperature rise of fast charging,and the influence curve of temperature rise is established by theoretical analysis and linear fitting method.(4)Through the rapid filling numerical simulation of shipborne hydrogen storage cylinders with different structural parameters,the larger the length-diameter ratio and the longer the extension length of straight pipe,the smaller the cyclic flow range and hydrogen velocity in the cylinder,and the worse the temperature rise in the cylinder.The smaller the opening,the faster the hydrogen flow,thus strengthening the convective heat transfer of the cylinder and thus reducing the temperature rise.