Experimental and numerical analysis of the in-cylinder swirl flow dependence on the pressure

The steady flow test rig is a device for studying the influence of the intake and exhaust ports of the cylinder head on the flow motion inside the cylinder in internal combustion engines. In this paper, the swirl flow as a critical mixing mechanism inside the cylinders of internal combustion engines has been investigated by the vane type swirl meter measurement system in the steady state flow test rig with experimental and numerical simulation methods. In numerical simulations, the in-cylinder flow in the presence of the swirl meter is modeled using the multiple reference frame (MRF) method. Three dimensional numerical simulations are applied by using the finite volume method. The simulation results show good agreement with experimental results and showed to be a good alternative to compensate the limitations of the operating conditions of the test rig. In this work, a linear correlation between the rotational speed of the swirl meter and the torque is found. The study also showed that by increasing the pressure difference between the inlet and outlet of the cylinder, the speed of the in-cylinder swirl flow increased where a correlation between swirl flow velocity and pressure difference is proposed using an exponential function. The in-cylinder swirl flow velocity was determined for different test pressure and for different distance the vane-type swirl meter from cylinder head and it was seen that it is maximum when the vane-type swirl meter is located at 1.3 D from cylinder head for different test pressure.