老轨业务5-1（Old rail service 5-1）.docVIP

老轨业务5-1（Old rail service 5-1） Fifth chapters Verse 1 Series supercharging surge: high load and high speed Individual pressurization surge: low load, big wave Parallel supercharging surge: low load, low speed, big wave When the diesel engine drives the propeller, the relationship between power and speed is also changed according to the law of propeller characteristics. This is the propulsion characteristic of diesel engine, and it is also a kind of (speed characteristic) Turbocharged diesel engine according to propulsion characteristic The speed increases, the coefficient of charge for C reduction, the load effect on phi C is very small As the speed increases, the excess air factor alpha decreases, and the reduction of the supercharged diesel engine alpha is smaller than that of the non supercharged one Turbocharged diesel engine according to speed characteristic When the speed rises, the speed booster rise at this time (the density of air gamma a increased than the coefficient of charge Phi C decreased (more), the excess air coefficient rise) Propulsion characteristics: power and speed of the 3 party is proportional to P=Cn3 The purpose of diesel engine management is to control (mechanical load and thermal load) within the rated range, that is, (limiting characteristics) When the ship sails 3, the main operating condition is on the 85% load (speed characteristic) line Turbocharged diesel engine throttle in constant speed drops, booster gas decreased, resulting in (compressor working point to the surge line), therefore the provisions of the work area, the restricted area is: (continuing work area of restricted areas or short-term work area restricted area) At the beginning of the speed decline, the torque (torque) is used as the main limiting object The latter is the main limiting object in the later period of the decline The supercharged diesel engine is much smaller than the average turbocharged diesel engine, because it is limited by the supercharger surge line Th