柴油机加速过程快速补气的电动增压器设计及其特性

为解决增压柴油机因传统增压器在加速时反应迟滞所带来的冒烟问题,研制了一台由高速无刷电动机独立驱动的电动增压器,转速范围从6．0～24．0 kr/min,最大流量达到0．1 kg／s。针对电动机的结构特点对电动增压器进行新颖的结构设计,使安装方便,简化了传统增压器所需的润滑措施。利用热线风速仪测定了其出口处在不同的转速下稳态时速度分布,分析稳态质量流量与增压比在不同转速下的变化趋势,并在不同的起动时间内(10 s,15 s,20 s,25 s)测定其瞬态响应,对其瞬态流量特性进行初步的研究,为柴油机在加速试验时与电动增压器匹配提供依据。研究结果表明,该电动增压器具有响应速度快、流量大、不受发动机工况所控制等特点,为降低其排放烟度、改善其加速性能提供一条可行的途径。

DESIGN AND CHARACTERISTICS ON ELECTRIC SUPERCHARGER FOR DIESEL ENGINE ACCELERATION BY ADDITIONAL AIR RAPID INJECTION

The electric supercharger driven by a brushless motor with high-speed is developed to solve the problem of acceleration smoke caused by the turbocharger sluggish response. Its rotate speed is from 6.0 r/min to 24.0 kr/min, and the maximum flux is 0.1 kg/s. The structure design of the electric supercharger is novel, which makes it dispensable to set the lubricating installation and easy to assemble. The velocity distribution at the outlet of the electric supercharger is determined by hot-wire anemometry under various rotate speeds in steady state. Further more, the trends of the flux and charge rate with various speeds are analyzed. In addition, the transient response is detected from motor setup to smooth running within 10s, 15 s, 20 s and 25 s respectively, and the characteristic of the transient flux is on pilot study. Research results indicate that the electric supercharger can respond rapidly with the great flux, and it is independent of the operating conditions of diesel engine. So it is a feasible way to reduce the smoke emission and improve the acceleration performance.