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.

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

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4036381 ◽

2017 ◽

Vol 139 (10) ◽

Cited By ~ 3

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.

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THREE DIMENSIONAL SIMULATION OF OIL FLOW CHARACTERISTICS IN LUBRICATION SYSTEM OF ROTARY TILLAGE ENGINE

INMATEH Agricultural Engineering ◽

10.35633/inmateh-65-17 ◽

2021 ◽

pp. 163-172

Author(s):

Junxiang Gao ◽

Xiaoliang Gao ◽

Wei Zou

Keyword(s):

Pressure Drop ◽

Three Dimensional ◽

Flow Characteristics ◽

Lubricating Oil ◽

Flow Index ◽

Lubrication System ◽

Pump Rotor ◽

Oil Pump ◽

Oil Flow ◽

Dimensional Simulation

Taking the lubrication system of rotary tillage engine as the research object, this paper makes a three-dimensional simulation study on the oil flow characteristics in the lubricating oil passage. The oil supply of the oil pump shall be greater than the circulating oil required by the lubrication system to ensure the lubrication of the rotary cultivator. Lubrication system is an important part to ensure the reliability and durability of rotary cultivator. The key component to achieve its performance is the oil pump. The geometric model of lubricating oil flow field in rotary tiller lubrication system is established by using FLUENT software. The results show that the pressure drop in the lubricating oil passage of the main bearing is the largest under the same working conditions. In the oil passage of the cylinder head, the pressure drop of the front main oil passage is the largest and the oil discharge is the largest. Add 1.6mm oil pump rotor on the basis of the thickness of the original oil pump rotor, the oil flow at the connecting rod nozzle reaches the flow index of the original rotary cultivator, and there is no cylinder pulling phenomenon of the rotary cultivator.

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Three-Dimensional Simulation of Turbulent Rectangular and Square Impinging Jet Flows

Volume 2, Parts A and B ◽

10.1115/ht-fed2004-56131 ◽

2004 ◽

Author(s):

Qingguang Chen ◽

Zhong Xu ◽

Yulin Wu ◽

Yongjian Zhang

Keyword(s):

Recirculation Zone ◽

Three Dimensional ◽

Flow Characteristics ◽

Adverse Pressure Gradient ◽

Impinging Jet ◽

Boundary Layer Separation ◽

Streamwise Velocity ◽

Impinging Jets ◽

Jet Flows ◽

Dimensional Simulation

Flow characteristics of turbulent impinging jets issuing, respectively, from a rectangular and a square nozzles have been investigated numerically through the solution of three-dimensional Navier-Strokes equations in steady state. Two geometries with two nozzle-to-plate spacings of four and eight times of hydraulic diameters of the jet pipes, and two Reynolds numbers of 20000 and 30000 have been considered with fully developed inlet boundary conditions. An RNG based k–ε turbulence model and a deferred correction QUICK scheme in conjunction with the wall function method have been applied to the prediction of the flow fields within semi-confined spaces. A common feature revealed by the computational results is the presence of a toroidal recirculation zone around the jet. An adverse pressure gradient is found at the impingement surface downstream the stagnation point. Boundary layer separation will occur if the gradient is strong enough, and the separation manifests itself as a secondary recirculation zone at the surface. In addition, three-dimensional simulations reveal the existence of two and four pronounced streamwise velocity off-center peaks at the cross-planes near to the impingement plate, respectively, in the rectangular and square impinging jet flows. These peaks are found forming at the horizontal planes where the wall jets start forming accompanied by two or four pairs of counter-rotating vortex rings. It is believed that the formation of the off-center velocity peaks is due to the vorticity diffusion along the wall jet as the jet impinges on the target plate.

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Three-dimensional simulation and experimental investigation of three-dimensional printed guiding devices on lattice-apron compact spinning

Textile Research Journal ◽

10.1177/0040517520982586 ◽

2020 ◽

pp. 004051752098258

Author(s):

Malik YH Saty ◽

Nicholus Tayari Akankwasa ◽

Jun Wang

Keyword(s):

Experimental Investigation ◽

Air Flow ◽

Flow Analysis ◽

Three Dimensional ◽

Flow Characteristics ◽

Yarn Properties ◽

3D Printed ◽

Dimensional Simulation ◽

Compact Spinning ◽

Set Up

The compact spinning system with a lattice apron utilizes air-flow dynamics to condense fibers in a bunch and enhance the yarn properties. One of the main challenges with this method is the lack of a comprehensive understanding of the air-flow field's effect in the condensing zone. This work presents a numerical and experimental investigation of the effects of three-dimensional (3D) printed guiding devices on the air-flow characteristics and yarn properties. Firstly, the 3D numerical model of the compact spinning system was set up based on the compact spinning machine geometrical dimensions. Secondly, different 3D prototypes were developed, simulated, and analyzed using computational fluid dynamics based on ANSYS software. The prototypes (A-type, B-type, and C-type), selected according to the simulation results, were then 3D printed to enable further experimental investigation. Air-flow analysis results in the air-suction flume area exhibiting a very high negative pressure, and the centerline zone was characterized by high velocity. Experimental results revealed that the three yarns spun with guiding devices had better strength, hairiness, and evenness than those spun without a guiding device. The model developed can be further improved and utilized for commercial purposes and is anticipated to improve compact spun yarn properties significantly.

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Numerical Study of Large Diameter Butterfly Valve on Flow Characteristics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1653 ◽

2011 ◽

Vol 236-238 ◽

pp. 1653-1657 ◽

Cited By ~ 1

Author(s):

Xiao Dong Wang ◽

Jing Liang Dong ◽

Tian Wang

Keyword(s):

Pressure Drop ◽

Flow Resistance ◽

Numerical Study ◽

Large Diameter ◽

Three Dimensional ◽

Flow Characteristics ◽

Numerical Approach ◽

Resistance Coefficient ◽

Butterfly Valve ◽

Dimensional Simulation

A numerical approach was used to investigate the flow characteristics around a butterfly valve with the diameter of 2108 mm by the commercial computational fluid dynamics (CFD) code FLUENT6.3. The simulation was carried out to predict flow field structure, flow resistance coefficient, hydrodynamics torque and so on, when the large diameter butterfly valve operated at various opening degrees. The three-dimensional simulation results shown that there are vortexes presented near valve back region as the opening degree smaller than 40 degree; the flow resistance coefficient reduces rapidly with the increasing of opening degree and the resistance coefficient is quite small as the angle larger than 50 degree; the hydrodynamic torque reduces with the increasing of opening degree and the hydrodynamic torque is smaller than 20% of maximum torque; the torque ratio and the pressure drop ratio are reduce with the increasing of opening degree, the pressure drop ratio reduces rapidly as the opening degree is smaller than 50 degree.

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A Three Dimensional Simulation of M-ICAR Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.516-517.54 ◽

2012 ◽

Vol 516-517 ◽

pp. 54-57

Author(s):

Quan Yue Geng ◽

Jie Wang ◽

Hong Wei Zhang ◽

Hui Jia

Keyword(s):

Water Level ◽

Flow Model ◽

Hydraulic Retention Time ◽

Volume Fraction ◽

Three Dimensional ◽

Great Influence ◽

Mixture Flow ◽

Phase Volume Fraction ◽

Dimensional Simulation ◽

Settling Process

Adopting standard k-ε turbulent model and mixture flow model, settling process and decant process was simulated using 3-d numerical simulation in M-ICAR(Mixture-Intermittently Cycle Aeration Reactor) process to analyze the changes of sludge phase volume fraction. The simulation results showed that the changes of feeding wastewater had great influence on sludge settle ability in decant process, and the position of decanter needed optimized; it had no influence on sludge settle ability in settling process. For considering the lowest hydraulic retention time, the research controlled maximum feeding wastewater for 1610m3/h. Internal recycle had no influence on sludge settle ability. Two methods were proposed: the first one, the water level of decanter was set 3.9m (sludge volume fraction of this suspended area was less than 0.05), feeding velocity was 0.07 m/s; the second, keep the water level of decanter 3.75 m, reduce feeding velocity (preliminary setting feeding velocity 0.06 m/s). The two methods had no influence on sludge settle ability.

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Experimental and numerical study of heat transfer and flow characteristics with different placement of the multi-deck display cabinet in supermarket

Open Physics ◽

10.1515/phys-2021-0023 ◽

2021 ◽

Vol 19 (1) ◽

pp. 256-265

Author(s):

Pei Yuan ◽

Qinghui Zeng ◽

Zhenglin Lei ◽

Yixiao Wu ◽

Yanli Lu ◽

...

Keyword(s):

Heat Transfer ◽

Temperature Distribution ◽

Numerical Study ◽

Three Dimensional ◽

Great Influence ◽

Flow Characteristics ◽

Air Curtain ◽

Face To Face ◽

Placement Method ◽

The Face

Abstract This work focuses on the heat transfer and flow characteristics with the different placement of the multi-deck display cabinet and tries to optimize the placement position of refrigerated display cabinet. First, the temperature distribution in a refrigerated display cabinet was experimentally investigated. The result showed that the food temperature in front is 3.6–4.8°C higher than back row of the same layer, and temperature fluctuation of 0.3–0.7°C less than the back row. Then, a three-dimensional numerical model of the display cabinet was established, and the k–ε model is employed to compare and analyze the heat transfer and air curtain characteristics. The results show that the placement methods have great influence on the performance of the display cabinet. The face-to-back placement method can acquire a better food refrigeration performance, and the food temperature of the face-to-back placement method is 0.3–0.5°C lower than that of the face-to-face placement method.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.744.211 ◽

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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