11-10-2016, 09:54 AM
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Abstract—The most important challenge facing car manufacturers today is to offer vehicles that deliver excellent fuel efficiency and better performance while maintaining cleaner emissions and driving comfort. Vehicle manufactures develop technology which can increase of performance and the engine can have a great power and torque. One of this technology is using Intelligence Variable Timing and Lift Electronic Control (i-VTEC) that can be used to solve problem above because it can control timing valve.i-VTEC is the new trend in Honda’s latest large capacity four cylinder petrol engine cars. The name is derived from ‘intelligent’ combustion control technologies that is outstanding fuel economy, cleaner emissions and reduced weight with high output and greatly improved torque at all speed range. VTC is able to advance and retard inlet valve opening by altering the phasing of the inlet camshaft to best match the engine load at any given moment. The two systems work in concern under the close control of the engine management system delivering improved cylinder charging and combustion efficiency, reduced intake resistance, and improved exhaust gas recirculation among the benefits. i-VTEC technology offers tremendous flexibility since it is able to fully maximize engine potential over its complete range of operation. In short Honda's i-VTEC technology gives us the best in vehicle performance.
INTRODUCTION
An internal combustion is defined as an engine in which the chemical energy of the fuel is released inside the engine and used directly for mechanical work. The man who is considered the inventor of the modern IC engine and the founder of the industry is Nikolaus Otto (1832-1891). I-VTEC was invented by Honda engineer Ikuo Kajitani. The i-VTEC system uses two camshaft profiles and hydraulically selects between profiles. From the past few decades, automobile industry has implemented many advance technologies to improve the efficiency and fuel economy of the vehicle. There are many of different engine systems are recently used: (Common Rail Diesel Injection System(CRDI), Direct Injection System(DI-System), Multi Point Fuel Injection(MPFI), Digital Twin Spark Injection(DTS-I), Quantum Core Engine, Programmed Electronic Fuel Injec-tion(PGM-FI), CDi Engine ( Capacitor Discharge Ignition) )
VTC controls of valve lift and valve duration are still limited to distinct low- and high-RPM profiles, but the intake cam-shaft is now capable of advancing between 25 and 50 degrees, depending upon engine configuration. Phasing is implemented by a computer-controlled, oil-driven adjustable cam gear. Both engine load and RPM affects VTC.
2.Literature Review
Jonas Suhardi (2014) , His research about Comparison Analysis Of Engine Performance Using i-VTEC System And Engine Without i-VTEC System Honda CR-V. His research concluded data from analysis torque and power. The highest engine torque can be reached when the engine use active VTEC system. The result from Dynamometer test showed that maximum torque from engine useactive i-VTEC is 211.7 Nm at 4900 Rpm and maximum torque from engine non-
Activei-VTEC is 202.8 Nm at 5350 Rpm.
HeriSubowo (2010), he study Mechanism of valve and kind of valve. Development of valve technology is expected increase engine power, fuel efficiency, lower exhaust emissions and friendly to the environment. Honda develop valve technology that name VTEC technology. Principle of the works is increase the amount of gas that is inserted into the cylinder with using engine speed to correction factor.
3. CASE STUDY
3.1 VALVE TIMING
Valve timing is a system that developed for measuring valve operation in relation to crankshaft position (in degrees), par-ticularly the points when the valves open, how long they remain open, and when the close.
MECHANISM OF I-VTEC
The mechanism has 3 cams with different timing and lift profile.
Stage 1 ( low speed ) : The 3 pieces of rocker arms moves in-dependently. Therefore the left rocker arm, which actuates the left inlet valve, is driven by the low-lift left cam. The right rocker arm, which actuates the right inlet valve, is driven by the medium-lift right cam .
Stage 2 ( medium speed ) : hydraulic pressure (painted orange in the picture) connects the left and right rocker arms together, leaving the middle rocker arm and cam to run on their own. As a result, both inlet valves obtain slow timing but medium lift.
Stage 3 ( high speed ) : hydraulic pressure connects all 3 rocker arms together. Since the middle cam is the largest, both inlet valve are actually driven by that fast cam. Therefore fast timing and high lift are obtain in both valves. Therefore fast timing and high lift is obtain in both valve.
3 Data Record
1. Power and torque can be obtained by running car on dynamometer. The procedure of data acquisition must be followed. For the first, shift the transmission on the D Lever. Running the car just like in normal condition then hold the enginthen hold the engine speed to 1500 Rpm. Push and Hold the gas pedal until engine reach 7500 Rpm. Then release the gas pedal and wait until engine back to normal condition again.
2. The output data can be read on the monitor that connect to dynamometer.
3. Repeat the step above up to four times experiments to get the accurate data.
4. ANALYSIS
4.1 Engine Torque
The highest torque generated by active i-vtec system is 211.7 Nm at 4900 Rpm and the highest torque generated by non-active i-vtec is 202.8 Nm at 5350 Rpm.
As the result, the mean average value of torque that resulted from engine using active i-VTEC is 200.03 Nm. On other hand, the mean average value of torque that resulted from engine non-active i-VTEC is 192.69 Nm. The engine torque using active i-VTEC is 3.67% higher than non-active i-VTEC engine. This occurs because the active i-VTEC is advancing the intake valves closing time and opened the intake valves for longer duration based on engine loads. The volumetric efficiency is improved by increasing amount of air that inhaled to combustion chamber which resulting to increasing torque.
CONCLUSION
i-VTEC system is more sophisticated than earlier variable-valve-timing systems, which could only change the time both valves are open during the intake/exhaust overlap period on the transition between the exhaust and induction strokes. By contrast, the i-VTEC setup can alter both camshaft duration and valve lift. i-VTEC Technology gives us the best in vehicle performance. Fuel economy is increased, emissions are reduced, derivability is enhanced and power is improved.
The maximum torque from engine use active i-VTEC is 211.7 Nm at 4900 Rpm and maximum torque from engine non-active i-VTEC is 202.8 Nm at 5350 Rpm. The engine torque using active i-VTEC is 3.67% higher than non-active i-VTEC engine. Torque will increase if the engine using active i-VTEC system. The maximum power from engine use active i-VTEC system is 181.5 Hp at 6910 Rpm and maximum power from engine non-active i-VTEC system is 167.7 Hp at 7020 Rpm. The engine power using active i-VTEC is 9.33% higher than non-active i-VTEC engine. Power will increase if the engine using active i-VTEC system.
Abstract—The most important challenge facing car manufacturers today is to offer vehicles that deliver excellent fuel efficiency and better performance while maintaining cleaner emissions and driving comfort. Vehicle manufactures develop technology which can increase of performance and the engine can have a great power and torque. One of this technology is using Intelligence Variable Timing and Lift Electronic Control (i-VTEC) that can be used to solve problem above because it can control timing valve.i-VTEC is the new trend in Honda’s latest large capacity four cylinder petrol engine cars. The name is derived from ‘intelligent’ combustion control technologies that is outstanding fuel economy, cleaner emissions and reduced weight with high output and greatly improved torque at all speed range. VTC is able to advance and retard inlet valve opening by altering the phasing of the inlet camshaft to best match the engine load at any given moment. The two systems work in concern under the close control of the engine management system delivering improved cylinder charging and combustion efficiency, reduced intake resistance, and improved exhaust gas recirculation among the benefits. i-VTEC technology offers tremendous flexibility since it is able to fully maximize engine potential over its complete range of operation. In short Honda's i-VTEC technology gives us the best in vehicle performance.
INTRODUCTION
An internal combustion is defined as an engine in which the chemical energy of the fuel is released inside the engine and used directly for mechanical work. The man who is considered the inventor of the modern IC engine and the founder of the industry is Nikolaus Otto (1832-1891). I-VTEC was invented by Honda engineer Ikuo Kajitani. The i-VTEC system uses two camshaft profiles and hydraulically selects between profiles. From the past few decades, automobile industry has implemented many advance technologies to improve the efficiency and fuel economy of the vehicle. There are many of different engine systems are recently used: (Common Rail Diesel Injection System(CRDI), Direct Injection System(DI-System), Multi Point Fuel Injection(MPFI), Digital Twin Spark Injection(DTS-I), Quantum Core Engine, Programmed Electronic Fuel Injec-tion(PGM-FI), CDi Engine ( Capacitor Discharge Ignition) )
VTC controls of valve lift and valve duration are still limited to distinct low- and high-RPM profiles, but the intake cam-shaft is now capable of advancing between 25 and 50 degrees, depending upon engine configuration. Phasing is implemented by a computer-controlled, oil-driven adjustable cam gear. Both engine load and RPM affects VTC.
2.Literature Review
Jonas Suhardi (2014) , His research about Comparison Analysis Of Engine Performance Using i-VTEC System And Engine Without i-VTEC System Honda CR-V. His research concluded data from analysis torque and power. The highest engine torque can be reached when the engine use active VTEC system. The result from Dynamometer test showed that maximum torque from engine useactive i-VTEC is 211.7 Nm at 4900 Rpm and maximum torque from engine non-
Activei-VTEC is 202.8 Nm at 5350 Rpm.
HeriSubowo (2010), he study Mechanism of valve and kind of valve. Development of valve technology is expected increase engine power, fuel efficiency, lower exhaust emissions and friendly to the environment. Honda develop valve technology that name VTEC technology. Principle of the works is increase the amount of gas that is inserted into the cylinder with using engine speed to correction factor.
3. CASE STUDY
3.1 VALVE TIMING
Valve timing is a system that developed for measuring valve operation in relation to crankshaft position (in degrees), par-ticularly the points when the valves open, how long they remain open, and when the close.
MECHANISM OF I-VTEC
The mechanism has 3 cams with different timing and lift profile.
Stage 1 ( low speed ) : The 3 pieces of rocker arms moves in-dependently. Therefore the left rocker arm, which actuates the left inlet valve, is driven by the low-lift left cam. The right rocker arm, which actuates the right inlet valve, is driven by the medium-lift right cam .
Stage 2 ( medium speed ) : hydraulic pressure (painted orange in the picture) connects the left and right rocker arms together, leaving the middle rocker arm and cam to run on their own. As a result, both inlet valves obtain slow timing but medium lift.
Stage 3 ( high speed ) : hydraulic pressure connects all 3 rocker arms together. Since the middle cam is the largest, both inlet valve are actually driven by that fast cam. Therefore fast timing and high lift are obtain in both valves. Therefore fast timing and high lift is obtain in both valve.
3 Data Record
1. Power and torque can be obtained by running car on dynamometer. The procedure of data acquisition must be followed. For the first, shift the transmission on the D Lever. Running the car just like in normal condition then hold the enginthen hold the engine speed to 1500 Rpm. Push and Hold the gas pedal until engine reach 7500 Rpm. Then release the gas pedal and wait until engine back to normal condition again.
2. The output data can be read on the monitor that connect to dynamometer.
3. Repeat the step above up to four times experiments to get the accurate data.
4. ANALYSIS
4.1 Engine Torque
The highest torque generated by active i-vtec system is 211.7 Nm at 4900 Rpm and the highest torque generated by non-active i-vtec is 202.8 Nm at 5350 Rpm.
As the result, the mean average value of torque that resulted from engine using active i-VTEC is 200.03 Nm. On other hand, the mean average value of torque that resulted from engine non-active i-VTEC is 192.69 Nm. The engine torque using active i-VTEC is 3.67% higher than non-active i-VTEC engine. This occurs because the active i-VTEC is advancing the intake valves closing time and opened the intake valves for longer duration based on engine loads. The volumetric efficiency is improved by increasing amount of air that inhaled to combustion chamber which resulting to increasing torque.
CONCLUSION
i-VTEC system is more sophisticated than earlier variable-valve-timing systems, which could only change the time both valves are open during the intake/exhaust overlap period on the transition between the exhaust and induction strokes. By contrast, the i-VTEC setup can alter both camshaft duration and valve lift. i-VTEC Technology gives us the best in vehicle performance. Fuel economy is increased, emissions are reduced, derivability is enhanced and power is improved.
The maximum torque from engine use active i-VTEC is 211.7 Nm at 4900 Rpm and maximum torque from engine non-active i-VTEC is 202.8 Nm at 5350 Rpm. The engine torque using active i-VTEC is 3.67% higher than non-active i-VTEC engine. Torque will increase if the engine using active i-VTEC system. The maximum power from engine use active i-VTEC system is 181.5 Hp at 6910 Rpm and maximum power from engine non-active i-VTEC system is 167.7 Hp at 7020 Rpm. The engine power using active i-VTEC is 9.33% higher than non-active i-VTEC engine. Power will increase if the engine using active i-VTEC system.