近曰,在德国法兰克福车展上,辉门动力总成推出i款史上最小的新型Rotocap?,也是第一款应用于每缸4气门轻型车发动机的气门旋转机构。这款气门旋转机构外观小巧,外径介于2 0~2 5 m m之间,可打包装入汽车动力总成系统的气门总成内。Rotocap...近曰,在德国法兰克福车展上,辉门动力总成推出i款史上最小的新型Rotocap?,也是第一款应用于每缸4气门轻型车发动机的气门旋转机构。这款气门旋转机构外观小巧,外径介于2 0~2 5 m m之间,可打包装入汽车动力总成系统的气门总成内。Rotocap?有助于加强气门旋转控制,进而应对气门总成润滑减少和发动机降速所引发减排和提高燃油效率的挑战。展开更多
Regenerative cooling with fuel as the coolant is used in the scramjet engine. In order to grasp the dynamic cha- racteristics of engine fuel supply processes, this article studies the dynamic characteristics of hydroc...Regenerative cooling with fuel as the coolant is used in the scramjet engine. In order to grasp the dynamic cha- racteristics of engine fuel supply processes, this article studies the dynamic characteristics of hydrocarbon fuel within the channel. A one-dimensional dynamic model was proved, the thermal energy storage effect, fuel volume effect and chemical dynamic effect have been considered in the model, the ordinary differential equations were solved using a 4th order Rungc-Kutta method. The precision of the model was validated by three groups of expe- rimental data. The effects of input signal, working condition, tube size on the dynamic characteristics of pressure, flow rate, temperature have been simulated. It is found that cracking reaction increased the compressibility of the fuel pyrolysis mixture and lead to longer responding time of outlet flow. The responding time of outlet flow can reach 3s when tube is 5m long which will greatly influence the control performance of the engine thrust system. Meanwhile, when the inlet flow rate appears the step change, the inlet pressure leads to overshoot, the overshoot can reach as much as 100%, such highly transient impulse will result in detrimental effect on fucl pump.展开更多
文摘近曰,在德国法兰克福车展上,辉门动力总成推出i款史上最小的新型Rotocap?,也是第一款应用于每缸4气门轻型车发动机的气门旋转机构。这款气门旋转机构外观小巧,外径介于2 0~2 5 m m之间,可打包装入汽车动力总成系统的气门总成内。Rotocap?有助于加强气门旋转控制,进而应对气门总成润滑减少和发动机降速所引发减排和提高燃油效率的挑战。
文摘Regenerative cooling with fuel as the coolant is used in the scramjet engine. In order to grasp the dynamic cha- racteristics of engine fuel supply processes, this article studies the dynamic characteristics of hydrocarbon fuel within the channel. A one-dimensional dynamic model was proved, the thermal energy storage effect, fuel volume effect and chemical dynamic effect have been considered in the model, the ordinary differential equations were solved using a 4th order Rungc-Kutta method. The precision of the model was validated by three groups of expe- rimental data. The effects of input signal, working condition, tube size on the dynamic characteristics of pressure, flow rate, temperature have been simulated. It is found that cracking reaction increased the compressibility of the fuel pyrolysis mixture and lead to longer responding time of outlet flow. The responding time of outlet flow can reach 3s when tube is 5m long which will greatly influence the control performance of the engine thrust system. Meanwhile, when the inlet flow rate appears the step change, the inlet pressure leads to overshoot, the overshoot can reach as much as 100%, such highly transient impulse will result in detrimental effect on fucl pump.
