Effect of Shroud and Orientation Angles of Inlet Valve on Flow Characteristic Through Helical–Spiral Inlet Port in Diesel Engine

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
A. Abd El-Sabor Mohamed ◽  
Saleh Abo-Elfadl ◽  
Abd El-Moneim M. Nassib
Keyword(s):  
Diesel Engine ◽  
Three Dimensional ◽  
Orientation Angle ◽  
Combustion Efficiency ◽  
Inlet Valve ◽  
Maximum Increase ◽  
Inlet Port ◽  
A Value ◽  
Engine Cylinder ◽  
Dimensional Simulation

The in-cylinder airflow motion is an important factor that severely affects combustion efficiency and emissions in diesel engines. It is greatly affected by the inlet port and valve geometries. A diesel engine cylinder with a helical–spiral inlet port is used in this study. An ordinary inlet valve and shrouded inlet valve having different shroud and orientation angles are used to study the shroud effect on the swirl and tumble motion inside the engine cylinder. Four shroud angles of 90 deg, 120 deg, 150 deg, and 180 deg are used. With each shroud angle, four orientation angles of 0 deg, 30 deg, 60 deg, and 90 deg are also used. Three-dimensional simulation model using the shear stress transport (SST) k–ω model is used for simulating air flow through the inlet port, inlet valve, and engine cylinder during both the intake and compression strokes. The results showed that increasing the valve shroud angle increases the swirl, and the maximum increase occurs at a valve shroud angle of 180 deg and orientation angle of 0 deg with a value of 80% with respect to the ordinary valve. But it decreases the volumetric efficiency, and the maximum decrement occurs at valve shroud of 180 deg and orientation angle of 90 deg with a value of 5.98%. Variations of the shroud and orientation angles have very small effect on the tumble inside the engine cylinder.

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

2017 ◽  
Vol 140 (3) ◽  
Author(s):  
Saleh Abo-Elfadl ◽  
A. Abd El-Sabor Mohamed
Keyword(s):  
Three Dimensional ◽  
Great Influence ◽  
Flow Characteristics ◽  
Volumetric Efficiency ◽  
Swirl Ratio ◽  
Inlet Valve ◽  
Inlet Port ◽  
Engine Cylinder ◽  
Port Design ◽  
Dimensional Simulation

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.

One-Dimensional Simulation of the Combustion Process in an Engine Cylinder with Ethanol

2014 ◽  
Vol 660 ◽  
pp. 447-451
Author(s):  
Akasyah M. Kathri ◽  
Rizalman Mamat ◽  
Amir Aziz ◽  
Azri Alias ◽  
Nik Rosli Abdullah
Keyword(s):  
Diesel Engine ◽  
Alternative Fuels ◽  
Engine Speed ◽  
Combustion Process ◽  
Cylinder Pressure ◽  
Ethanol Fuel ◽  
One Dimensional ◽  
Engine Cylinder ◽  
Dimensional Simulation ◽  
The One

The diesel engine is one of the most important engines for road vehicles. The engine nowadays operates with different kinds of alternative fuels, such as natural gas and biofuel. The aim of this article is to study the combustion process that occurs in an engine cylinder of a diesel engine when using biofuel. The one-dimensional numerical analysis using GT-Power software is used to simulate the commercial four-cylinder diesel engine. The engine operated at high engine load and speed. The ethanol fuel used in the simulation is derived from the conventional ethanol fuel properties. The analysis of simulations includes the cylinder pressure, combustion temperature and rate of heat release. The simulation results show that in-cylinder pressure and temperature for ethanol is higher than for diesel at any engine speed. However, the mass fraction of ethanol burned is similar to that of diesel. MFB only affects the engine speed.

Free Modal Analysis of a 2-Cylinder Diesel Engine Cylinder Block

2010 ◽  
Vol 29-32 ◽  
pp. 310-314
Author(s):  
Zhong Cai Zheng ◽  
Na Liu ◽  
Yan Gao ◽  
Kun Jin Zhang ◽  
Hai Ou Chen
Keyword(s):  
Diesel Engine ◽  
Modal Analysis ◽  
Three Dimensional ◽  
Engine Block ◽  
Cylinder Block ◽  
Mode Shapes ◽  
Relative Distribution ◽  
Three Dimensional Model ◽  
Engine Cylinder ◽  
Vibration Magnitude

The three dimensional model of a 2-cylinder diesel engine block is established with the P ro/E software, and then the modal analysis of the engine block is carried out using finite element method with ANSYS software . Through the analysis, the inherent frequencies and mode shapes of the first 6 order modes are obtained respectively, and then are compared with the testing result; comparison shows the results of FEA estimation are in good agreement with those of testing which indicates the FEA results’ correctness. The results of the relative distribution of the vibration magnitude in the whole block are given, which provide necessary guides for the dynamic optimal design of the engine block.

scholarly journals Effect of Early Closing of the Inlet Valve on Fuel Consumption and Temperature in a Medium Speed Marine Diesel Engine Cylinder

2020 ◽  
Vol 8 (10) ◽  
pp. 747
Author(s):  
Vladimir Pelić ◽  
Tomislav Mrakovčić ◽  
Vedran Medica-Viola ◽  
Marko Valčić
Keyword(s):  
Diesel Engine ◽  
Numerical Model ◽  
Fuel Consumption ◽  
Engine Performance ◽  
Nox Emissions ◽  
Inlet Valve ◽  
Engine Operation ◽  
Medium Speed ◽  
Engine Cylinder ◽  
Marine Diesel

The energy efficiency and environmental friendliness of medium-speed marine diesel engines are to be improved through the application of various measures and technologies. Special attention will be paid to the reduction in NOx in order to comply with the conditions of the MARPOL Convention, Annex VI. The reduction in NOx emissions will be achieved by the application of primary and secondary measures. The primary measures relate to the process in the engine, while the secondary measures are based on the reduction in NOx emissions through the after-treatment of exhaust gases. Some primary measures such as exhaust gas recirculation, adding water to the fuel or injecting water into the cylinder give good results in reducing NOx emissions, but generally lead to an increase in fuel consumption. In contrast to the aforementioned methods, the use of an earlier inlet valve closure, referred to in the literature as the Miller process, not only reduces NOx emissions, but also increases the efficiency of the engine in conjunction with appropriate turbochargers. A previously developed numerical model to simulate diesel engine operation is used to analyse the effects of the Miller process on engine performance. Although the numerical model cannot completely replace experimental research, it is an effective tool for verifying the influence of various input parameters on engine performance. In this paper, the effect of an earlier closing of the intake valve and an increase in inlet manifold pressure on fuel consumption, pressure and temperature in the engine cylinder under steady-state conditions is analysed. The results obtained with the numerical model show the justification for using the Miller processes to reduce NOx emissions and fuel consumption.

Three-Dimensional Simulation of the Intake Port Combination Effect on Intake Flow Characteristic in a Highly Intensified Diesel Engine

2013 ◽  
Vol 744 ◽  
pp. 211-214
Author(s):  
Hong Meng Li ◽  
Guo Xiu Li ◽  
Yuan Jing Hou ◽  
Yu Song Yu
Keyword(s):  
Diesel Engine ◽  
Flow Characteristic ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Intake Port ◽  
Intake Process ◽  
Instantaneous Flow Field ◽  
Dimensional Simulation ◽  
Cfd Method ◽  
Intake Flow

In this paper, the three-dimensional CFD method is used in numerical simulation of the highly intensified diesel engine intake process. The effect of different intake flow compound modes on the highly intensified diesel engine is studied (Including compounded port with helical and tangential intake port, compounded port with two helical intake ports and compounded port with two tangential intake ports). By contrasting the instantaneous flow field, flow characteristic and inlet ability of the three compound modes, the pattern of influence on the inlet flow characteristics by compound modes is analyzed. The results indicate that the combinations of the intake port greatly affect the swirl rate and the inlet ability. The interference of the two helical intake ports is serious, causing more inlet loss. The two helical intake ports have the weakest inlet ability among the three types of intake ports. However, two helical intake ports can cause higher swirl rate. Two tangential intake ports inlet ability is the most excellent, but its swirl rate is the lowest.

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