A patented double-ring-plate gear reducer was designed and its dynamic performance was simulated. One unique characteristic of this novel drive is that the phase angle difference between two parallelogram mechanisms i...A patented double-ring-plate gear reducer was designed and its dynamic performance was simulated. One unique characteristic of this novel drive is that the phase angle difference between two parallelogram mechanisms is a little less than 180 degree and four counterweights on two crankshafts are designed to balance inertia forces and inertia moments of the mechanisms. Its operating principle, advantages, and design issues were discussed. An elasto-dynamics model was presented to acquire its dynamic response by considering the elastic deformations of ring-plates, gears, bearings, etc. The simulation results reveal that compared with housing bearings, planetary bearings work in more severe conditions. The fluctuation of loads on gears and bearings indicates that the main reason for reducer vibration is elastic deformations of the system rather than inertia forces and inertia moments of the mechanisms.展开更多
Thermal upgrading of vacuum residue mixed with waste plastics was studied in a laboratory scale delayed coking unit.The model of feed thermal decomposition was set up and the first order reaction kinetics was used to ...Thermal upgrading of vacuum residue mixed with waste plastics was studied in a laboratory scale delayed coking unit.The model of feed thermal decomposition was set up and the first order reaction kinetics was used to predict products distribution during the coking process.The distillate yield was higher(70%) for the vacuum residue/polystyrene(VR/PS) feed system and the vacuum residue/low density polyethylene(VR/LDPE) feed system.The resulted distillate yield was separated into fractions according to their boiling points,with gasoline and diesel being our fractions of concern.The activation energy was higher for gasoline production(around 60 kcal/mol) varying with the type of feed system,while it was 33 kcal/mol for diesel fraction.The regression coefficient R was 0.990.展开更多
基金Supported by the Key Project of Ministry of Education of China ( No.106050)National Natural Science Foundation of China(No.50205019)Doctoral Foundation of Ministry of Education of China(No.20040056018) .
文摘A patented double-ring-plate gear reducer was designed and its dynamic performance was simulated. One unique characteristic of this novel drive is that the phase angle difference between two parallelogram mechanisms is a little less than 180 degree and four counterweights on two crankshafts are designed to balance inertia forces and inertia moments of the mechanisms. Its operating principle, advantages, and design issues were discussed. An elasto-dynamics model was presented to acquire its dynamic response by considering the elastic deformations of ring-plates, gears, bearings, etc. The simulation results reveal that compared with housing bearings, planetary bearings work in more severe conditions. The fluctuation of loads on gears and bearings indicates that the main reason for reducer vibration is elastic deformations of the system rather than inertia forces and inertia moments of the mechanisms.
文摘Thermal upgrading of vacuum residue mixed with waste plastics was studied in a laboratory scale delayed coking unit.The model of feed thermal decomposition was set up and the first order reaction kinetics was used to predict products distribution during the coking process.The distillate yield was higher(70%) for the vacuum residue/polystyrene(VR/PS) feed system and the vacuum residue/low density polyethylene(VR/LDPE) feed system.The resulted distillate yield was separated into fractions according to their boiling points,with gasoline and diesel being our fractions of concern.The activation energy was higher for gasoline production(around 60 kcal/mol) varying with the type of feed system,while it was 33 kcal/mol for diesel fraction.The regression coefficient R was 0.990.