Helical Inlet Design And Research

Diesel Engine work process and overall performance depends on matching between the fuel supply and injection system, intake system and air movement and combustion chamber shape (referred to as oil, gas, room). As the small and medium sized high-speed direct injection diesel engine needs strong intake swirl, squish compression and combustion turbulence, its intake port generally made spiral or tangential shape. Compared with tangential intake port, the spiral intake port has greater swirl strength and volumetric efficiency, is widely used in small single-cylinder diesel engine. Therefore, the research on structural parameters and location layout of the helical intake port is very important.This paper compares the forward and reverse design method, which current widely used in helical intake port design, do research on the diesel engine helical intake port design. Based on Parameter equation expression construct the diesel engine spiral screw segment, thereby establishing a forward model of intake port design method can quickly and accurately complete the development of a new spiral intake port. Through reverse Software -- Imageware can accurately reverse design helical intake port.To better understand the structural parameters of Helical intake port influence on swirl ratio and flow coefficient, and designed a helical intake port meet the design requirements. In this paper, through three-dimensional modeling software UG designed 11 programs intake port with different entrance shape, entrance height, spiral height and helical screw section angle. The different spiral intake port design's steady flow simulation experiments show that:swirl ratio and flow coefficient showing the shift in the trend, The quality of the intake port shape design plays a vital role on the flow coefficient as the swirl ratio certain. As the intake valve eccentricity (cylinder radial position) affect the uniformity,isotropic and flow speed of air flow inside the cylinder, so the arrangement of the intake port location is equally important. The intake valve Eccentricity calculations show:The eccentricity within 0.2～0.33 in the best area, flow coefficient is larger, when the eccentricity was 0.33 to 0.41, you can get a relatively large swirl ratio. Finally, simulate the transient intake process on FIRE and reveals the shape, size and number of vortex flow, swirl flow, and other air flow in the cylinder relations with the crank angle.