Helical Inlet Port Research Articles

The Effect of the Helical Inlet Port Design and the Shrouded Inlet Valve Condition on Swirl Generation in Diesel Engine

Inlet port design has a great influence on swirl generation inside the engine cylinder. In this paper, two helical inlet ports having the same helix design were suggested. The first has an upper entrance, and the second has a side entrance. With the two ports, shrouded inlet valves having different conditions of shroud and orientation angles were used. Four shroud angles were used; they are 90 deg, 120 deg, 150 deg, and 180 deg. Also, four orientation angles were used; they are 0 deg, 30 deg, 60 deg, and 90 deg. Three-dimensional simulation model using the shear stress transport k–ω model was used for predicting the air flow characteristics through the inlet port and the engine cylinder in both intake and compression strokes. The results showed that the side entrance port produces swirl ratio higher than that of the upper entrance port by about 3.5%, while the volumetric efficiency is approximately the same for both ports. For both the ports, increasing the valve shroud angle increases the swirl ratio and reduces the volumetric efficiency. The maximum increments of swirl ratio relative to the ordinary valve case occur at valve conditions of 30–150 deg, 0–180 deg, and 30–180 deg. At these valve conditions, the swirl ratio values are 6.38, 6.72, and 6.95 at intake valve close (IVC) with percentage increments of 69.2%, 78.2%, and 84.4%, respectively. The corresponding values of the volumetric efficiency are 93.6, 92.5, and 91.2, respectively, with percentage decrements of 2.84%, 4%, and 5.7%, respectively.

Effect of Helix Parameter Modification onFlow Characteristics of CIDI Diesel EngineHelical Intake Port

This project work involves experimental investigation of helical inlet port flow characteristics for cylinder head of Direct Injection (D.I) diesel engine. The average flow coefficient and swirl number is obtained using a paddle wheel test bench. Intake port helix parameters, i.e., distance between peripheral side wall and valve axis ‘Dp’, width of helical section parallel to valve axis ‘W’ and initial width of the helix ‘Wh’ are measured for different flow boxes for selected different bore and stroke engines. These parameters are modified and detailed analysis has been done to establish the effect on swirl number and average flow coefficient. The second part of work focused on the Computation Fluid Dynamics (CFD) to study flow velocity, flow distribution inside cylinder and to analyze effect of helix parameter change. The experimental study of combined effect of helix parameters, ‘W’, ‘Wh’ and ‘Dp’ indicates that this modification can be initiated for improving flow characteristics if change required in average flow coefficient is small as compared to higher amount of change required in swirl number. The CFD analysis with this modification also shows improvement in swirl generation and flow distribution.

English

English

Design and Analysis of Intake Port of Diesel Engine for Target Value of Swirl

The mutual desire for higher fuel economy and greater performance along with stringent emission regulations set by the government for diesel engines necessitates enhanced air-fuel mixing for proper combustion. The design of intake port plays a major role in an engine design, development and optimization, as it controls the power developed, fuel consumed and exhaust emissions from the engine. The effects of different geometrical parameters of helical port on swirl performance were studied. A methodology is proposed for the design of helical inlet port of diesel engine in order to achieve target value of 1.8 swirl number. The computational fluid dynamics approach is used for analysis of intake port performance. The port performance of prototype flow box was analyzed experimentally on a steady flow rig. The observed mean swirl number and flow capacity values satisfy the requirements.

Effects of Different Deviations of Helical Inlet Port on Performance

In this paper, the helical inlet port of CZ4B26 diesel engine is studied. Its3-D solid models of port with the axial deviation and rotated port are made to research the effect on helical inlet port performance. Based on the validation of CFD precision by test, the numerical simulation of flow characteristics in ports-valve-cylinder system is carried out. The results showed that the axial deviation of the port and rotated port have a range of effects on the performance of inlet port.