GAS-DYNAMIC FEATURES OF STATIONARY AIR FLOW ADMISSION INTO A CYLINDER THROUGH A POPPET VALVE AND CROSS PROFILED CHANNELS

The paper presents experimental data on velocity fields of a steady flow in the cylinder as it is filled with air through a poppet valve and channels in a cylinder head (CH) with cylinders of various cross section shapes (a circle, a square, and a triangle). The investigations were carried out on a laboratory stand simulating the main elements of the intake system of a reciprocating engine. A steady-state motion in the gas-dynamic system was created using a compressor settling the air from the cylinder. The average air flow velocity in the intake manifold was from 2 to 5 m / s. The investigations into the structure of the flow in the cylinder were carried out using a 2D PIV system. It has been established that the shape of the CH channel cross section has a substantial effect in the air flow distribution in the reciprocating engine cylinder. It is shown that in using a round cannel, there is a flow motion in CH along the side walls and there is virtually no flow in the center of the cylinder. The use of a square channel results in a more uniform filling of the entire cylinder volume with air. The installation of a CH with a triangular channel leads to the formation of a large-scale flow swirl inside the cylinder. The obtained data create a scientific foundation for designing intake systems with improved gas exchange quality indicators and promising characteristics of recipro- cating engines

Author:  L. V. Plotnikov, D. A. Davydov, D. N. Krasil′nikov, and V. A. Shurupov
Keywords:  cylinder admission, cylinder head channel, poppet valve, steady air flow, velocity field, reciprocating engine, PIV method
Page:  655