黏度指数改进剂对汽油机油燃油经济性的影响

Effect of Viscosity Index Improvers on Fuel Economy of Gasoline Engine Oils

就一种氢化苯乙烯双烯共聚物和三种聚甲基丙烯酸酯黏度指数改进剂对汽油机油燃油经济性的影响进行了研究。用高频往复试验仪模拟发动机的摩擦情况,通过测定摩擦因数来考察汽油机油的润滑性能。汽油机油的摩擦因数越小,润滑性能越好,越有利于提高燃油经济性。用发动机倒拖试验测定汽油机油的摩擦扭矩,并与参比油的摩擦扭矩进行比较。扭矩差(扭矩差=参比油摩擦扭矩的平均值-汽油机油的摩擦扭矩)越大,汽油机油的燃油经济性越好。用运动黏度(100℃运动黏度890 mm^2/s)较小,剪切稳定性(剪切稳定性指数5)较好的聚甲基丙烯酸酯调配的0W-20黏度等级的汽油机油的摩擦因数较小,扭矩差较大,具有较好的燃油经济性。根据NEDC(New European Driving Cycle)模拟循环试验油耗计算,可以提高0.28%的燃油经济性。

The effect of a hydrogenated styrene diene copolymer and three polymethacrylate viscosity index improvers on the fuel economy of gasoline engine oil was studied.The friction of the engine was simulated with high-frequency reciprocating rig, then the lubricity of the gasoline engine oil was studied by measuring the friction factor.The smaller the friction factor of gasoline engine oil ,the better the lubricity ,the more conducive to improve fuel economy.The friction torque of the gasoline engine oil was measured by the motoring friction loss test and it was compared with the friction torque of the reference oil.The greater the torque difference was （torque difference -the average value of the reference oil friction torque - the friction torque of the gasoline engine oil）, the better the fuel economy of the gasoline engine oil was.The friction coefficient of the 0W-20 viscosity grade gasoline engine oil blended with polymethacrylate with smaller kinematic viscosity（kinematic viscosity at 100 ℃ 890 mm^2/s）, better shear stability （shear stability index 5 ） was small and torque difference was big, and had good fuel economy. According to NEDC （New European Driving Cycle ） simulation cycle test fuel consumption calculation, the fuel economy could improve 0.28%.