A Study of Cycle-to-Cycle Variations and the Influence of Charge Motion Control on In-Cylinder Flow in an IC Engine

2010 ◽  
Vol 132 (5) ◽  
Author(s):  
Mayank Mittal ◽  
Harold J. Schock
Keyword(s):  
Velocity Field ◽  
Probability Density ◽  
Motion Control ◽  
Combustion Engine ◽  
Control Valve ◽  
Multiple Point ◽  
Charge Motion ◽  
Ic Engine ◽  
Molecular Tagging Velocimetry ◽  
Cylinder Flow

An experimental study is performed to investigate the cycle-to-cycle variations and the influence of charge motion control on in-cylinder flow measurement inside an internal combustion engine assembly. Molecular tagging velocimetry (MTV) is used to obtain the multiple point measurement of the instantaneous velocity field. MTV is a molecular counterpart of particle-based techniques, and it eliminates the use of seed particles. A two-component velocity field is obtained at various crank angle degrees for tumble and swirl measurement planes inside an optical engine assembly (1500 rpm and 2500 rpm engine speeds). Effects of charge motion control are studied considering different cases of: (i) charge motion control valve (CMCV) deactivated and (ii) CMCV activated. Both the measurement planes are used in each case to study the cycle-to-cycle variability inside an engine cylinder. Probability density functions of the normalized circulation are calculated from the instantaneous planar velocity to quantify the cycle-to-cycle variations of in-cylinder flows. In addition, the turbulent kinetic energy of flow is calculated and compared with the results of the probability density function. Different geometries of CMCV produce different effects on the in-cylinder flow field. It is found that the charge motion control used in this study has a profound effect on cycle-to-cycle variations during the intake and early compression; however, its influence reduces during the late compression. Therefore, it can be assumed that CMCV enhances the fuel-air mixing more than the flame speed.

Evaluating the Influence of Charge Motion Control on In-Cylinder Flow Using MTV

2008 ◽  
Author(s):  
M. Mittal ◽  
H. J. Schock ◽  
R. Sadr
Keyword(s):  
Velocity Field ◽  
Motion Control ◽  
Combustion Process ◽  
Control Valve ◽  
Multiple Point ◽  
Charge Motion ◽  
Ic Engine ◽  
Molecular Tagging Velocimetry ◽  
Air Mixing ◽  
Cylinder Flow

An experimental study is performed to investigate the effects of charge motion control on flow measurement inside an internal combustion (IC) engine assembly. Molecular Tagging Velocimetry (MTV) is used to obtain the multiple point measurement of the instantaneous velocity field. MTV is a molecular counterpart of PIV based techniques, and it eliminates the use of seed particles. A two-dimensional velocity field is obtained at various crank angle degrees (CADs) for tumble and swirl measurement planes inside an optical engine assembly [1500 and 2500 rpm engine speeds]. Effects of charge motion control are studied considering different cases of: (i) Charge motion control valve (CMCV) deactivated and (ii) CMCV activated. Both the measurement planes are used in each case to study the cycle-to-cycle variability inside an engine cylinder. Probability density functions (PDFs) of the normalized circulation (NC) are calculated from the instantaneous planar velocity to quantify the cycle-to-cycle variations of in-cylinder flows. Different geometries of CMCV produce different effects on the in-cylinder flow field. It is found that the CMCV used in this work has a profound effect on fuel-air mixing; however, its influence is not as significant during the late compression. Therefore, it can be assumed that CMCV has less contribution to enhance the flame speed during the combustion process.

scholarly journals Experiment and Investigation in Reducing Emission from an IC Engine by using Inlet Helical Roller

2021 ◽  
Vol 23 (10) ◽  
pp. 318-326
Author(s):  
S. Rajendran ◽  
◽  
K. Ganesan ◽  
K. Sakthivel ◽  
SM. Murugesan ◽  
...  
Keyword(s):  
Combustion Engine ◽  
Intake Manifold ◽  
Major Influence ◽  
Ic Engine ◽  
Inlet Stream ◽  
Flow Formation ◽  
Small Change ◽  
And Performance ◽  
Cylinder Flow ◽  
Combustion Processes

This research paper reports that in-cylinder flow formation in a combustion engine has a major influence on the combustion, emission and performance characteristics. Air and fuel enters the combustion chamber of an engine throughout the intake manifold with high velocity. So, it introduces a helical roller in the path of inlet stream of mixture. It achieved the swirl by using a component that could be easily integrated into any existing engines at low engine speed. The performance of the engine increases and completes the combustion, leads to reduced emissions and small change in volumetric efficiency. It is also proved that increased swirl movement introduces helical roller that helps the flame spread which used into constant heat transfer rate. This suggests to a new combustion technique that should be developed to yield improved primary combustion processes in-side the engine with significantly reduced exhaust gas emissions.

Classifying IC Engine Swirl Fields by Complex Moments

2019 ◽  
Author(s):  
Kwee-Yan Teh ◽  
Penghui Ge ◽  
Fengnian Zhao ◽  
David L. S. Hung
Keyword(s):  
Velocity Field ◽  
Flow Field ◽  
High Speed ◽  
Flow Fields ◽  
Flow Patterns ◽  
Analysis Approach ◽  
Flow Mode ◽  
Mean Velocity ◽  
Ic Engine ◽  
Cylinder Flow

Abstract Engine in-cylinder flow varies from cycle to cycle, which contributes to variation of the mixing and combustion processes between fuel and air. Such flow field cyclic variability at the macroscopic scale is distinct from random fluctuations at the microscopic scale about the ensemble mean velocity field due to turbulence. At the extreme, the mean velocity field may bear no resemblance to any instantaneous flow field within the ensemble. Rather, these instantaneous fields may appear multimodal. Yet previous attempts to define and identify the flow modes were either qualitative (by visual inspection), or based on strict point-by-point velocity difference between two flow fields. The former approach is clearly subjective; the latter does not accommodate translational and rotational variations of in-cylinder flow patterns relative to a flow mode. Such spatial variations, in location and orientation, of the flow patterns can be quantified by the technique of complex moment normalization. The algebraic properties of complex moments are also intimately related to the geometric and physical properties of two-dimensional/two-component flow fields. In this paper, we take the normalized moments as flow field attributes for further cluster analysis. This analysis approach is demonstrated using a set of in-cylinder flow fields obtained by high-speed particle image velocimetry on a swirl plane of a research optical engine operating under low intake swirl setting. The resulting classification of the flow fields into several clusters (flow modes) are discussed, and the potential and limitations of the analysis approach are appraised.

scholarly journals Recovery of Exhaust Waste Heat for ICE Using the Beta Type Stirling Engine

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Wail Aladayleh ◽  
Ali Alahmer
Keyword(s):  
Internal Combustion Engine ◽  
Waste Heat ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Stirling Engine ◽  
Gas Temperature ◽  
Ic Engine ◽  
Exhaust Waste Heat ◽  
Useful Power ◽  
Shaft Power

This paper investigates the potential of utilizing the exhaust waste heat using an integrated mechanical device with internal combustion engine for the automobiles to increase the fuel economy, the useful power, and the environment safety. One of the ways of utilizing waste heat is to use a Stirling engine. A Stirling engine requires only an external heat source as wasted heat for its operation. Because the exhaust gas temperature may reach 200 to 700°C, Stirling engine will work effectively. The indication work, real shaft power and specific fuel consumption for Stirling engine, and the exhaust power losses for IC engine are calculated. The study shows the availability and possibility of recovery of the waste heat from internal combustion engine using Stirling engine.

Ethers and esters as alternative fuels for internal combustion engine: A review

2021 ◽  
pp. 146808742110464
Author(s):  
Yang Hua
Keyword(s):  
Alternative Fuels ◽  
Combustion Engine ◽  
Combustion Process ◽  
Pressure Rise ◽  
Engine Performance ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Future Research ◽  
Particulate Emissions ◽  
Ic Engine

Ether and ester fuels can work in the existing internal combustion (IC) engine with some important advantages. This work comprehensively reviews and summarizes the literatures on ether fuels represented by DME, DEE, DBE, DGM, and DMM, and ester fuels represented by DMC and biodiesel from three aspects of properties, production and engine application, so as to prove their feasibility and prospects as alternative fuels for compression ignition (CI) and spark ignition (SI) engines. These studies cover the effects of ether and ester fuels applied in the form of single fuel, mixed fuel, dual-fuel, and multi-fuel on engine performance, combustion and emission characteristics. The evaluation indexes mainly include torque, power, BTE, BSFC, ignition delay, heat release rate, pressure rise rate, combustion duration, exhaust gas temperature, CO, HC, NOx, PM, and smoke. The results show that ethers and esters have varying degrees of impact on engine performance, combustion and emissions. They can basically improve the thermal efficiency of the engine and reduce particulate emissions, but their effects on power, fuel consumption, combustion process, and CO, HC, and NOx emissions are uncertain, which is due to the coupling of operating conditions, fuel molecular structure, in-cylinder environment and application methods. By changing the injection strategy, adjusting the EGR rate, adopting a new combustion mode, adding improvers or synergizing multiple fuels, adverse effects can be avoided and the benefits of oxygenated fuel can be maximized. Finally, some challenges faced by alternative fuels and future research directions are analyzed.

Investigation of Swirl Ratio Impact on In-Cylinder Flow in a SIDI Optical Engine

2015 ◽  
Author(s):  
Hanyang Zhuang ◽  
David L. S. Hung ◽  
Jie Yang ◽  
Shaoxiong Tian
Keyword(s):  
Flow Field ◽  
Soot Formation ◽  
Flow Characteristics ◽  
Control Valve ◽  
Exhaust Emission ◽  
Swirl Ratio ◽  
Optical Engine ◽  
Crank Angle ◽  
Cylinder Flow ◽  
Intake Swirl

Advanced powertrain technologies have improved engine performance with higher power output, lower exhaust emission, and better controllability. Chief among them is the development of spark-ignition direct-injection (SIDI) engines in which the in-cylinder processes control the air flow motion, fuel-air mixture formation, combustion, and soot formation. Specifically, intake air with strong swirl motion is usually introduced to form a directional in-cylinder flow field. This approach improves the mixing process of air and fuel as well as the propagation of flame. In this study, the effect of intake air swirl on in-cylinder flow characteristics was experimentally investigated. High speed particle image velocimetry (PIV) was conducted in an optical SIDI engine to record the flow field on a swirl plane. The intake air swirl motion was achieved by adjusting the opening of a swirl ratio control valve which was installed in one of the two intake ports in the optical engine. Ten opening angles of the swirl ratio control valve were adjusted to produce an intake swirl ratio from 0.55 to 5.68. The flow structures at the same crank angle degree, but under different swirl ratio, were compared and analyzed using proper orthogonal decomposition (POD). The flow dominant structures and variation structures were interpreted by different POD modes. The first POD mode captured the most dominant flow field structure characteristics; the corresponding mode coefficients showed good linearity with the measured swirl ratio at the compression stroke when the flow was swirling and steady. During the intake stroke, strong intake air motion took place, and the structures and coefficients of the first modes varied along different swirl ratio. These modes captured the flow properties affected by the intake swirl motion. Meanwhile, the second and higher modes captured the variation feature of the flow at various crank angle degrees. In summary, this paper demonstrated a promising approach of using POD to interpret the effectiveness of swirl control valve on in-cylinder swirl flow characteristics, providing better understanding for engine intake system design and optimization.

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