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Fig. 21. Graphical representation of the proceedings related to the further development of the test bench.

Figure 21 Graphical representation of the proceedings related to the further development of the test bench.

Related Figures (20)

Fig. 1. Passenger car powertrain system development [5] sented by Kyrtatos et al. [7] combines the analysis of fun- damental aspects and the application of the tested technical solution in a closed application-fundamentals-application cycle. For this purpose, simulations and experiments per- formed with modern tools are used. The experimental part includes the study of fundamental phenomena carried out using a constant volume chamber with optical access, opti- cal testing on a single cycle RCEM machine using assumed geometry and finally on a single cylinder research engine close to the production engine. The engine research results are the implementation of new highly advanced systems that reduce fuel consumption, which translates directly into lower GHG emissions [8]. Engine manufacturers indicate the possibility of fuel effi- ciency improvement in the range of 20-30% by implement- ing, e.g. variable compression ratio VCR, cylinder deactiva- tion or application of unconventional work cycles of Atkin- son/Miller engine in the hybrid drive system. Also, the combustion of lean mixtures, decreasing the combustion temperature, and spark-assisted compression ignition sys- tem are attractive [9]. The outlook for further development of internal com- bustion engines based on the automotive industry is related to the necessity of meeting future emission standards, espe- cially CO, limits [3, 4]. In order to meet future standards, efforts are being made, leading to the electrification of powertrains. Parallel work is being carried out to improve the ICE. Figure | shows the evolution of the propulsion system, whose priority in the initial phase of development was low cost and high reliability (ICE 1.0) to technological- ly advanced hybrid systems (ICE 4.0) based on the close cooperation of the internal combustion engine with the electric system [5].
Fig. 1. Passenger car powertrain system development [5] sented by Kyrtatos et al. [7] combines the analysis of fun- damental aspects and the application of the tested technical solution in a closed application-fundamentals-application cycle. For this purpose, simulations and experiments per- formed with modern tools are used. The experimental part includes the study of fundamental phenomena carried out using a constant volume chamber with optical access, opti- cal testing on a single cycle RCEM machine using assumed geometry and finally on a single cylinder research engine close to the production engine. The engine research results are the implementation of new highly advanced systems that reduce fuel consumption, which translates directly into lower GHG emissions [8]. Engine manufacturers indicate the possibility of fuel effi- ciency improvement in the range of 20-30% by implement- ing, e.g. variable compression ratio VCR, cylinder deactiva- tion or application of unconventional work cycles of Atkin- son/Miller engine in the hybrid drive system. Also, the combustion of lean mixtures, decreasing the combustion temperature, and spark-assisted compression ignition sys- tem are attractive [9]. The outlook for further development of internal com- bustion engines based on the automotive industry is related to the necessity of meeting future emission standards, espe- cially CO, limits [3, 4]. In order to meet future standards, efforts are being made, leading to the electrification of powertrains. Parallel work is being carried out to improve the ICE. Figure | shows the evolution of the propulsion system, whose priority in the initial phase of development was low cost and high reliability (ICE 1.0) to technological- ly advanced hybrid systems (ICE 4.0) based on the close cooperation of the internal combustion engine with the electric system [5].
Fig. 2. Combustion engines technology upgrades and implementation status [10]
Fig. 2. Combustion engines technology upgrades and implementation status [10]
Fig. 3. Research engines types [14, 22, 32, 33]
Fig. 3. Research engines types [14, 22, 32, 33]
Fig. 4. Elements of the applied variable phase execution system [31]
Fig. 4. Elements of the applied variable phase execution system [31]
Optimization of pre-combustion chamber for the CNG engine with turbulent jet ignition Fig. 5. Relationship between electric motor speed and advance and retard timing [34]
Optimization of pre-combustion chamber for the CNG engine with turbulent jet ignition Fig. 5. Relationship between electric motor speed and advance and retard timing [34]
Fig. 6. Optical scanning process of an camshaft control motor using GOM's ATOS Core engine cylinder head equipped with a spark jet ignition sys- tem [35, 36] using only non-destructive methods. Therefore, two non-contact measurement methods were used. The first stage consisted of optical scanning of the outer planes using the ATOS II Triple Scan measurement system. Due to its accuracy and versatility, this system is used in industry and scientific institutions [37]. Using the laser triangulation method (used in the discussed cylinder-head reconstruction method), the measuring system consists of a laser light source displayed as a line, the measuring object, and a cam- era as a photosensitive element. Working with an overhead projector, stereoscopic cameras capture three views of an object within a single measurement. This technology requires fewer scans, providing higher quality data even when scan- ning shiny surfaces or complex geometric figures. Optical scans were realized both for the manufactured test engine cylinder head and the individual components mounted in the system (Fig. 6 and 7) and the location of the cylinder head on the engine (Fig. 8).
Fig. 6. Optical scanning process of an camshaft control motor using GOM's ATOS Core engine cylinder head equipped with a spark jet ignition sys- tem [35, 36] using only non-destructive methods. Therefore, two non-contact measurement methods were used. The first stage consisted of optical scanning of the outer planes using the ATOS II Triple Scan measurement system. Due to its accuracy and versatility, this system is used in industry and scientific institutions [37]. Using the laser triangulation method (used in the discussed cylinder-head reconstruction method), the measuring system consists of a laser light source displayed as a line, the measuring object, and a cam- era as a photosensitive element. Working with an overhead projector, stereoscopic cameras capture three views of an object within a single measurement. This technology requires fewer scans, providing higher quality data even when scan- ning shiny surfaces or complex geometric figures. Optical scans were realized both for the manufactured test engine cylinder head and the individual components mounted in the system (Fig. 6 and 7) and the location of the cylinder head on the engine (Fig. 8).
Fig. 8. Optical scanning process of area of driveline Fig. 7. Scanning process diagram
Fig. 8. Optical scanning process of area of driveline Fig. 7. Scanning process diagram
the lighting conditions. The two CCD cameras used realise approx. five million measuring points in an interval of a few seconds. The projector of the measurement head pro- jects the sequence of stripes on the measured object (Fig. 9), while the CCD cameras record their course. By solving the optical transformation equations, the system calculates the coordinates for each camera pixel with high accuracy. The result of a single measurement is a point cloud that unambiguously reflects the scanned surface. The measure- ment is saved in STL (Standard Triangle Language) format, which needs to be converted into a 3D project.
the lighting conditions. The two CCD cameras used realise approx. five million measuring points in an interval of a few seconds. The projector of the measurement head pro- jects the sequence of stripes on the measured object (Fig. 9), while the CCD cameras record their course. By solving the optical transformation equations, the system calculates the coordinates for each camera pixel with high accuracy. The result of a single measurement is a point cloud that unambiguously reflects the scanned surface. The measure- ment is saved in STL (Standard Triangle Language) format, which needs to be converted into a 3D project.
Fig. 9. Projection of a sequence of stripes on the measured object cial to ensure the correct operation of the system. In order to determine the internal areas of the cooling channels as well as the inlet and outlet channels, a CT scan was per- formed.
Fig. 9. Projection of a sequence of stripes on the measured object cial to ensure the correct operation of the system. In order to determine the internal areas of the cooling channels as well as the inlet and outlet channels, a CT scan was per- formed.
Fig. 11. View of the test engine headspace during tomographic examina- tion The range of Hounsfield units for CT is —1000 to +4000, and it allows the image to be represented in shades of grey. Only 256 gray levels are used in practice, which is a selected slice of the CT number value. It makes it possible to observe the image with high contrast, thus enabling the interpretation of the measurement result (Fig. 11).
Fig. 11. View of the test engine headspace during tomographic examina- tion The range of Hounsfield units for CT is —1000 to +4000, and it allows the image to be represented in shades of grey. Only 256 gray levels are used in practice, which is a selected slice of the CT number value. It makes it possible to observe the image with high contrast, thus enabling the interpretation of the measurement result (Fig. 11).
Fig. 10. Location of the research engine head in a GE tomographic scanner model V/Tome/x m
Fig. 10. Location of the research engine head in a GE tomographic scanner model V/Tome/x m
Fig. 12. Methodology tomographic inspection with linear detector crease the measuring accuracy, the method with a linear detector is used (Fig. 10 and 12). This method consists in reducing the radiation beam by means of an aperture to a flat beam. Using a linear detector and rotating 360°, a flat X-ray image of a single slice of the test object is obtained. In order to obtain a spatial image of the entire workpiece, it is necessary to move the object in the vertical plane addi- tionally. During measurements of the cylinder head, the measurement resolution was 2 mm in the Y-axis, allowing recognition of the geometries necessary for the design of the cylinder head internal volumes (Fig. 13).
Fig. 12. Methodology tomographic inspection with linear detector crease the measuring accuracy, the method with a linear detector is used (Fig. 10 and 12). This method consists in reducing the radiation beam by means of an aperture to a flat beam. Using a linear detector and rotating 360°, a flat X-ray image of a single slice of the test object is obtained. In order to obtain a spatial image of the entire workpiece, it is necessary to move the object in the vertical plane addi- tionally. During measurements of the cylinder head, the measurement resolution was 2 mm in the Y-axis, allowing recognition of the geometries necessary for the design of the cylinder head internal volumes (Fig. 13).
Fig. 13. Design of the internal spaces of the cooling system — view of the measurement point cloud obtained from the tomographic scanning process
Fig. 13. Design of the internal spaces of the cooling system — view of the measurement point cloud obtained from the tomographic scanning process
Fig. 15. Visualization of reference and modified cylinder head length comparison based on optical scan results
Fig. 15. Visualization of reference and modified cylinder head length comparison based on optical scan results
Fig. 14. Comparison of the developed model with the image obtained by scanning along with the specified deviations
Fig. 14. Comparison of the developed model with the image obtained by scanning along with the specified deviations
Fig. 18. Valve timing diagram after cylinder head modification
Fig. 18. Valve timing diagram after cylinder head modification
Fig. 17. The CAD model of modified cylinder head and the valve train system
Fig. 17. The CAD model of modified cylinder head and the valve train system
Fig. 19. Cylinder pressure curves for two different intake camshaft modes The development and implementation of the cylinder head equipped with the described system of electronically controlled valve timing phases allow conducting cycle-by- cycle research for precise analysis of transients. Recording the combustion process during a controlled change of the cylinder filling strategy will allow more accurate identifica- tion of combustion systems dedicated to hybrid power- trains.
Fig. 19. Cylinder pressure curves for two different intake camshaft modes The development and implementation of the cylinder head equipped with the described system of electronically controlled valve timing phases allow conducting cycle-by- cycle research for precise analysis of transients. Recording the combustion process during a controlled change of the cylinder filling strategy will allow more accurate identifica- tion of combustion systems dedicated to hybrid power- trains.
Fig. 20. Waterfall diagram showing the change in compression pressure during changes in the timing system adjustment The result of the work is a modified engine design that allows research on low-emission combustion systems using the VVT-iE technology. In the future, the test stand will be used for comprehensive analysis of the combustion process and validation of computer simulations, the course of which is presented in Fig. 21.
Fig. 20. Waterfall diagram showing the change in compression pressure during changes in the timing system adjustment The result of the work is a modified engine design that allows research on low-emission combustion systems using the VVT-iE technology. In the future, the test stand will be used for comprehensive analysis of the combustion process and validation of computer simulations, the course of which is presented in Fig. 21.
Related topics:
Internal Combustion EngineAutomotive EngineeringCombustion enginesHead cylinder
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