Engine performance and fuel economy development with intake manifold

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Engine Performance and Fuel Economy Development with Intake Manifold 01 Engine performance and fuel economy development with intake manifold Author Taehwan Kim General Manager, Managed Programs LLC (tkim@managed-programs.com) Donald Carbone President, Managed Programs LLC (dcarbone@managed-programs.com) Abstract Intake and exhaust manifold has been widely used either as flow distributor to/from each cylinders or as tuning device for specific tuning purpose. Recently with the help of ECS(Engine Cycle Simulation) tools like GT-power, AVL-Boost and Wave, all engine builders have been trying to develop engine performance and NVH development through intake and exhaust manifold system. After economic crisis in 008, due to higher gas price and enforced emission regulation all over the world, most of engine builders are trying to research reasonable solution to meet this entire demand and expectation and focused to develop more fuel efficient engine with better performance. Hybrid engine system, Turbo charged DI diesel engine, GDI and Turbo charged intercooled GDI engines are gaining more and more popularity for better performance and for improved fuel economy goal and HCCI engine is under vigorous research to implement this goal as well. GDI, Dual CVVT and CVVL system, Cylinder Deactivation System, Energy recovery system like KERS, ISG (Idle Stop-n-Go) system, electric steering pump and electric water pump are all tends to be recently tried for adoption by all auto manufacturers to achieve better fuel economy and to meet the fuel economy goal. But either adoption of new internal combustion system or latest new features has significant cost impact to engine manufacturing cost and imposes huge difficulty for auto manufacturer to tolerate. However, despite of its huge contribution to performance and fuel economy, intake/exhaust manifold system has not been properly researched and studied due to its complicacy and difficulty and lack of understanding on its fluid dynamics, combustion and wave tuning behavior. Managed Programs LLC has been working with many worldwide OEMs and 1 st Tiers to support to achieve their performance goal through intake/exhaust system development since 1997 and also working with several Chinese OEMs and 1 st tiers to help their engine performance and fuel economy development through our proprietary Intake Manifold Wave Tuning technology. Here we d like to introduce how our Intake Manifold Wave Tuning technology can help to improve engine performance, fuel economy and thermal efficiency. 1 Introduction (1) Spark ignition engine development For the last several decades, engine performance has been one of the hot topics by all auto engine manufacturers. Engine performance figures like maximum power and torque have been widely used not only as a measure of their performance, but also to demonstrate how good performance it has and all auto OEMs have been investing huge amount of money to develop better performance. Even though using bigger sized engine can be the easiest way to get higher power, due to auto taxation system combined with engine displacement and due to increased demand for better fuel economy, latest effort by all auto OEMs are focused on how to achieve high specific horse power and torque at ordinary operation speed. Making it harder, owing to growing demand for better fuel economy, higher torque at ordinary driving range like low to mid speed torque and lower BSFC is more and more highlighted on top of maximum power and torque figures. () Engine performance development method In an effort to achieve such high performance goal, ECS like AVL-Boost, GT-Power and WAVE and CFD (Computational Fluid Dynamics) like STAR-CCM+, FLUENT, CFX are widely used to research the concept for both intake manifold and exhaust manifold design. But without Page 1 of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 proper understanding on wave interaction by intake/exhaust manifold combined with fluid dynamics and combustion efficiency, we observe majority of OEMs and 1 st Tiers going failure to achieve their performance or fuel economy goal. This failure used to be caused not only by inappropriate analysis method, but also by poor understanding on the physics through intake/exhaust manifold and lack of thorough understanding on internal combustion engine. Through this paper, we d like to explain on what usual engine developer mistakes and why ECS results used to predict unexpected result without good correlation from actual engine dyno test result and what technical difficulty we have when trying to achieve the performance through current ECS and CFD method. Also Managed Programs LLC s proprietary Intake/Exhaust manifold wave tuning method will be presented as a measure to overcome this difficulty. Engine Performance Design Tool Performance Development ( ~ 1990) CFD Dyno Test N-m, HP No variable Features Performance Development ( ~ 000) ECS Dyno Test N-m, HP Partial variable Features CFD Before 1990s, most engine performance development effort through intake/exhaust manifold was focused on how to minimize flow restriction through intake and exhaust manifold. Even if numerous engineers researched how intake/exhaust manifold could develop different tuning characteristics, but most manifold engineers were focused on flow restriction minimization after empirical selection of runner length and dimension. During this period, CFD result made fairy good correlation with dyno test result and development direction was so straight forward that if CFD result showed less pressure drop, then we could expect performance improvement. After 1990s, with the introduction of ECS method, engine performance and NVH development made big jump combined with CFD. With the help of ECS, engine developers could concept their intake/exhaust manifold properly per their performance goal and then they finalize their design through CFD fine tuning for smooth flow. Recently, after 000s, with the help of high capacity engine control system, various variable engine control system started to be used widely for most spark ignition internal combustion engine like CVVT (Continuously Variable Valve Timing), CVVL (Continuously Variable Valve Lift) system as well as Variable spark timing control system and Variable Induction System. All these systems were developed to optimize all valve train and air/fuel system to work at the optimal operation condition at all operation speeds so as to produce the best performance and fuel economy at all times. Owing to these all variable control system features, engine builders could achieve fairy high engine performance all around operation speed range. But unfortunately, all these new variable control systems adoption make ECS and CFD engineers to face with huge difficulty in making reasonable prediction for upcoming engine dyno test results if intake manifold engineer develop the manifold based on their ECS and CFD result with remarkable improvement result, then actual engine dyno test results tend to reveal unbelievably opposite result. Performance Development ( 000 ~ ) ECS Dyno Test N-m, HP Fully variable Features CFD All this may be due to incomplete understanding on fluid dynamics, combustion and wave interaction of intake manifold by most ECS and CFD engineers. So as to properly implement Page of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 intake manifold development for performance development, thorough understanding on both wave interaction and combustion theory, combined with appropriate engine dyno test knowledge with variable engine control systems are extremely critical. Below is one of the examples to show the impact of variable control features to engine dyno test result. We ran an engine dyno test to see the impact of variable control systems. The test was performed with baseline engine control setting without any change, which was already set after optimization for baseline, and the test results were compared only by switching baseline manifold with performance manifold. When all variable engine control parameters were optimized, Performance Manifold was already proven to produce roughly 10HP more power than baseline one. The test result with baseline control set revealed even lower maximum power with Performance Manifold than baseline manifold even with increased air flow into the engine. This tells very important fact that with any variable control features adopted, any change in engine tuning characteristic should come with all variable control system optimization all the times. Also so as to make reasonable performance prediction with ECS, proper parameter set for all these variable control features are extremely critical. Unfortunately predicting it with accuracy without actual dyno testing is very hard, and it may be why most of engine builders are outsourcing for this ECS model build from dedicated engine development companies in Europe. But another usual mistake most of ECS engineers are making is their assumption that the model can be used for all cases, and this is very easy to mislead to wrong development direction because the ECS model and combustion model was constructed only for that specific case intended. Below chart shows the difference between actual dyno tests versus ECS simulation. Actual Dyno. Test Manifold Parameters Optimization 1) C.A, AFR ) IVO, EVO MBT or Max. Brake Torque? N-m, KW AVL-Boost / GT-Power Manifold Parameters Thermo Dynamics Wave interaction Combustion Analysis N-m, KW Very difficult to find optimum value To be conclusive with ECS analysis, we should pay extreme attention to above fact. Unless all variable engine control parameters are properly set, all ECS output and performance prediction tends to mislead to wrong direction and practical standpoint, acquiring and updating all those proper control parameters every time is not easy for ordinary OEMs due to insufficient knowledge, information and experience like advanced engine builders in Europe. 3 Alternative method for intake/exhaust performance tuning ECS simulation is 1-Dimensional analysis combined with combustion, fluid dynamics and wave interaction theories. As it produces combined prediction result of fluid dynamics, combustion efficiency with wave interaction, all those three factors should be considered at the same time without failure and this is heavily related to all engine control parameters set as well. For better understanding on the details of engine performance factors by means of ECS simulation, we can categorize it into three major parts, which is related to 1) combustion efficiency, ) volumetric efficiency, 3) Friction Loss. Combustion Efficiency Charge Motion Spark Timing Fuel Enrichment Compression Ratio Engine Cooling Intake/Exhaust System Volum etric Efficiency Valve Timing/Lift Valve overlap Intake Manifold Exhaust Manifold Head port Friction Loss FM E P Flow Restriction Back pressure Combustion Chamber Air induction System Exhaust System Crank Shaft Page 3 of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 (1) Combustion efficiency Intake and exhaust manifold have significant influence to combustion efficiency especially under part load condition. For instances, if the intake manifold is with swirl control or tumble control device installed, with the valve control activated, the engine may make significant spark advance than the intake manifold which is not equipped with such devices at part load condition. But at full load condition, so as to produce the maximum performance and to enable maximum flow with least flow restriction, these devices tend to be deactivated and spark timing and fuel enrichment tends to be optimized for maximum torque at widely open condition. In other words, if we only consider MBT condition under full load, then we may be able to assume only optimal condition, that way we may be able to exclude all combustion efficiency related influence out of consideration. This is especially true to low to mid speed full load performance that with traditional engine setup with fixed spark timing set, low to mid speed torque tends to be dominated by spark advance as wells as volumetric efficiency. If we assume only optimal combustion efficiency condition for all speed range, it may be possible to make the performance quite dependent only upon volumetric efficiency. () Volumetric Efficiency There are numerous factors which influencing volumetric efficiency. Variable valve mechanism like CVVT and CVVL affect engine performance dramatically, and it is usually designed to extract the best performance over entire speed range without diminishing any potential tuning effect by intake or exhaust manifold. Therefore if we assume full load condition performance with fully load variable valve train system, then we can also assume optimal valve timing adjustment to best match with intake and exhaust manifold tuning. Crank shaft or firing order configuration is also another critical factors to decide volumetric efficiency or engine tuning characteristics and it is very important factor especially for V6, I6, V8, V10 engines. Intake and exhaust manifold concept should be followed by crank shaft firing concept as well based on ideal system concept. As a conclusion, by assuming that all valve train system or engine components as well as intake/exhaust manifold system are designed at optimal condition, we can make intake/exhaust manifold isolated from all other control parameters which is conjugated with intake and exhaust manifold. This way, we can only concentrate on intake and exhaust manifold system to evaluate its best performance to get the maximum performance. But the most important thing is to get the proper understanding on each component characteristic. For example, if we focus intake manifold development to maximize reflective wave tuning effect, while intake CAM is designed to minimize friction loss even with lower tuning effect, then this will result in extremely poor performance result. Therefore the most critical knowledge for tuning is how to analyze each engine components fluid dynamic, combustion and wave interaction behavior to best match with intake and exhaust manifold development concept. (3) Friction loss Friction loss is one of the key factors to decide BSFC. Friction loss plays very important role both to performance and fuel consumption. Flow restriction through induction system and back pressure through exhaust system are one of the key factors for performance and this places significant impact to engine performance, but rarely tend to alter engine tuning characteristics. So only by analyzing flow minor loss factor through intake manifold and exhaust manifold, we can consider this effect without any difficulty. Conclusively on alternative analysis method for intake and exhaust manifold development concept, by assuming that variable engine control parameters set as optimal condition for whole valve train system and air fuel and combustion control system, and by evaluating friction loss through flow minor loss analysis, optimum intake and exhaust manifold design concept is possible only by focusing on volumetric efficiency optimization, combined with fluid dynamics and wave interaction, this helps to isolate volumetric efficiency effect from combustion efficiency implication, which always making ECS simulation accuracy in jeopardy. This way, we can only concentrate on intake and exhaust manifold system to evaluate its best performance to get the Page 4 of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 maximum volumetric efficiency at concerned engine speed. But one of the most important aspects to be taken with great care is how to get the proper understanding on each engine components characteristics. If we focus intake manifold development to induce the maximum reflective wave tuning effect, while the intake CAM is focused on flow loss minimization and if the intake manifold is tuned for maximum inertia charging effect, while crank shaft firing is intended for resonance tuning for that speed, then resulting intake and exhaust manifold design concept can t produce any reasonable performance result as we expect. 4 Fundamentals of intake/exhaust wave tuning. (1) Intake resonance tuning effect Pressure pulsations inside the intake manifold can create very strong acoustic resonance modes. If the resonance effect is properly aligned with the engine firing frequency for performance tuning, this can help to improve engine performance as well. Resonance strength tends to be mitigated as it goes to high frequency, so this effect is useful for mostly low- to mid-speed performance development. For I4 engine application and 60 degree V6 or I6 engine configuration with split plenum concept and Porsche s boxer 6 cylinder engines, this effect helps to improve low- to mid speed torque. The below illustration shows V6 engine torque curves with a variable resonance intake manifold. Through design concept optimization, all below torque curves can be achieved by proper concept and optimization. X1 ( k1 iwc1)( k mw ) X 0 ( k1 k m1w iwc1)( k mw ) k if we assume C1 0 (no damping condition) X1 k1( k mw ) X 0 ( k1 k m1w )( k mw ) k m (1 w ) k k m m k (1 w )(1 w ) k1 k k k1 w (1 ) w k (1 w w k )(1 ) k 1 w w k1 Above is the frequency response function of DOF vibration system including internal combustion engines induction system and it may illustrate how intake manifold with plenum and zip tube system react with each other. As shown below, by adequately optimizing intake manifold configuration, fine resonance tuning from low speed to high speed is possible. X1 X 0 w w Ferrari has been applying this resonance tuning concept to its V8 engines and recently introduced California 458 model with 4.5L V8 engine to make 570HP@9000RPM and 540 N- m@6000rpm. Not all V8 engine is applicable with this resonance tuning, but some V8 engine with flat plane crank shaft is available to apply this concept. () Reflective wave tuning When the intake valve closes, the air flowing inside runner is suddenly blocked by the air intake valve and a strong compression wave is generated and propagated back to the intake manifold at the local speed of sound relative to the flow velocity. When the compression wave reaches to plenum, it reflects back towards intake valve as an expansion wave and with still valve closed, it Page 5 of 10

Pressure Pressure Engine Performance and Fuel Economy Development with Intake Manifold 01 bounces back to plenum and again back to intake valve. If the timing is appropriate that the compression wave arrives at the intake valve at the beginning of the intake valve opening, raising the pressure above the nominal inlet pressure, this allows more air to be forced into the cylinder. With maximum utilization of reflective wave tuning, significant volumetric efficiency improvement over 0% is possible. IVO IVC With refl. Wave tuning Reflective wave tuning effect raises the charged air pressure at the beginning of intake process and this can significantly reduce pumping loss by reducing FMEP and also charged air pressure inside cylinder is increased as much owing to this. Furthermore, significant fuel economy improvements are also possible with an intake manifold designed to optimize reflective wave tuning. Below P-V diagram illustrate how well designed reflective wave tuned intake manifold can help to get higher performance and lower BSFC. P-V Ref. Wave tuning wave tuning effect and this is important to get highest BMEP and lowest BSFC. (3) Inertia charging When intake valve opens, the air suddenly rushes into the cylinder and an expansion wave propagates back toward plenum at the local speed of sound relative to the flow velocity. When the expansion wave reaches plenum, it reflects back towards intake valve as a compression wave. The time it takes for the round trip depends on the length of the runner. If the timing is appropriate for compression wave arrives at the intake valve before the intake process completed which raises the pressure above the nominal inlet pressure, allowing more air to be charged at the end of intake cycle. Runner configuration should be carefully decided to enable the best inertia charging effect and this is also very important to secure broad torque band all over the engine operation range. IVO IVC With Inertia charging With no tuning Below shows P-V diagram with inertia charging effect present P-V inertia charging P-V no. Tuning P-V no. Tuning From above P-V diagram, BMEP ref. wave tuning > BMEP no. tuning BSFC ref. wave tuning < BSFC no. tuning Manifold configuration and intake valve lift profile should be carefully matched to maximize reflective (4) RAM effect As air flows inside the runner, the runner plays the role of a velocity stack and the pressure Page 6 of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 keep increasing with raised air velocity (high RPM) inside it. This effect becomes progressively more important with increasing engine speeds. First phase is Analytic wave tuning phase and this is rather analytic and theoretical analysis phase. During this phase, all fluid dynamics and wave tuning characteristics are thoroughly analyzed and input for parametric study for performance tuning. If ECS model is available, ECS analysis is also performed in parallel for comparison, but 1-D ECS model doesn t have to be necessarily simulated. And all intake/exhaust manifold related parameters are determined based on this parametric study. Second phase is 3D Wave tuning phase. This is the process to correlate designed geometry with physical dimensions and parameters. What we designed is based on CAD geometry, and it doesn t represent physical or acoustic geometry, but 3D geometric geometry. During 3D Wave tuning phase, all 3D design parameters are fine tuned to match with physical meaning. From above illustration, with larger runner diameter, we easily notice that the maximum peak torque drops significantly. This is because air inertia momentum inside the runner is reduced significantly with the larger runner diameter due to increased flow area, which eventually lowers kinetic energy and pressure of the air mass inside cylinder. When using RAM effect, runner configuration should be carefully decided to guarantee maximum kinetic energy at tuned speed. 5 Engine performance development process through Intake/Exhaust manifold Wave Tuning Kick-Off Production YES Meet DV/PV? Product Design ECU Mapping Program Requirement - Low end torque - Max torque & Max power - Others : BSFC, NVH NO Analytic WaveTuning - System resonance tuning - Inertia & Reflective wave tuning - RAM Effect NO Meet Performance? Engine Dyno. Test Concept design - System configuration - Runner profile (Length, Diameter) 1D Engine Cycle Simulation - Volumetric efficiency, BSFC - Max torque - Max power 3D Wave Tuning Meet Design Intent? YES RP Design & build Our wave tuning technology is comprised of two steps of wave tuning process. NO Intended runner length? (based on 3D CAD) physical runner length? 3D wave tuning process is mainly for fine tuning of the manifold, but it is also very important to implement our customers expectation to the best. Usual engineering tolerance for engine performance development used to accept +/- 500 RPM difference in rated torque RPM and +/- 50 RPM difference in rate power RPM, but Managed Programs LLC used to design our intake/exhaust manifold to match the rated torque and power RPM by with +/- 100RPM difference after 1~ RP designs so far and it is all related to combined effort of Analytic wave tuning and 3D wave tuning. 6 Intake manifold design strategy based on applications (1) Fuel Economy One of the easiest misunderstandings with intake manifold system development is that the longer the runner is, the better low speed torque is. At low to mid speed range, as flow velocity inside manifold is so low that there is no sufficient kinetic energy for pressure charging. So as to improve low speed torque, which is mainly aimed for lower gear 4 3 1 Page 7 of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 ratio adoption, or to achieve lower BSFC itself, the intake manifold system should be designed to maximize its intake resonance effect and reflective wave tuning effect at low speed. Just adding runner length can help to improve low speed torque to some level, but due to high flow restriction due to longer runner length, BSFC tends to dramatically increase. a. Resonance intake manifold system. 37.0 36.0 35.0 34.0 33.0 3.0 31.0 30.0 1500 000 500 3000 3500 4000 4500 5000 5500 6000 6500 b. Reflective wave tuned manifold RPM compression ratio and better combustion efficiency became the critical key for turbo engine success. Under this circumstance, the role of intake manifold and wave tuning concept need to be aligned well for engine s development concept as well. The biggest technical huddle with turbo application is how to overcome combustion instability and this is heavily related to high entropy of air fuel mixture at the beginning of compression cycle due to high boost pressure and compression ratio. This is even going worse as the engine speed going higher above 5000RPM due to increased RAM effect. This is why most of turbo charged spark ignition engine application has the rated power showing around 5000RPM and for most turbo charged spark ignition engine with high boost pressure, this used to be the technical barrier to come over. So as to overcome this combustion instability issue at high speed, intake manifold tuning should be focused to keep the air entropy as low as possible and that way, we can manage more power at higher engine speed. Below P-V diagrams show the conceptual diagram on how to control the combustion efficiency by intake manifold wave tuning. () Turbo charger application Owing to high boost pressure, ideal thermal cycle for turbo application forms a little bit different intake process as shown below than naturally aspired one. 3 3 i 3 6 e 5 6 k 1 T T1 r Typical turbo engine Isentropic Process k Pv const 4 1 s=s s=s 1 3 4 i 6 1 6 5 e With negative wave tuning 4 e 6 5 i 6 1 Ordinary N.A engine 4 i 6 1 e 6 5 Turbo Charging Porsche introduced this concept for their Carrera 911 GT Turbo engine as a name of Expansion Manifold. In the past, due to poor combustion efficiency of turbo charged engine, usual turbo charged spark ignition engine had to adopt pretty low compression ratio. Recently with the help of high capacity intercooler system development, more efficient engine cooling system design and anti-knocking fuel control system adoption like GDI system, auto manufacturers tend to adopt much higher compression ratio for higher thermal efficiency. For several reasons, higher Recently many OEMs started to research more to implement this goal. (3) VIS(Variable Induction System) Page 8 of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 VIS manifold has been regarded as the combination of two different runner length manifolds into one manifold and with switching valve in it, both different runner length manifolds are to be working per separate engine condition. Unfortunately this used to be one of the easiest misunderstandings by all engineers on VIS manifold. Even though VIS manifold is designed as an integration of two different runner length manifolds into one system, physics inside manifold, fluid dynamics, combustion characteristics and governing wave equation are pretty different, and there should be VIS valve assembly located in some place inside the manifold and this used to provide extra flow restriction to the flow across the valve system. Therefore proper understanding on the physics inside VIS manifold is very important and VIS manifold optimization should be constructed based on this understanding. without risk. This must be combined effort with all required engineering consideration applied upfront. Now as most of OEMs tend to directly go from Rapid Proto phase to production tooling phase skipping prototype tooling phase, this becomes the most important technical aspects. With VIS system provisioned, all engineering concerns like NVH, durability, tooling and manufacturing should be considered upfront during concept phase and we even recommend considering fuel economy, ECU calibration strategy and RP build plan during concept phase upfront. Recently, we observed many OEMs and 1 st tiers were in trouble due to many issues they didn t aware in the beginning like, a. Serious performance loss during production tooling phase with actual VIS system installed, after initial engine performance confirmed through Rapid Proto test without VIS assy. Brake Torque Long Runner Manifold Short Runner Manifold Brake Torque VIS Long VIS Short b. Huge performance loss during production tooling phase or excessively increased part cost after performance confirmed with RP part which was built under no tooling and manufacturing process consideration. 1000 4000 000 3000 5000 6000 Two different Manifolds 1000 4000 000 3000 5000 6000 Optimized VIS Combination Without proper system understanding, achieving the similar level of performance defined by each single length manifolds is not possible. But with complete optimization of VIS concept, even better performance than the combination of two different length manifolds test results is even possible except for small areas and all these are related to VIS manifold optimization. Performance Tuning, CFD Fuel Economy, ECU Calibration Rapid Proto Plan NVH, Durability Tooling, Manufacturing Appropriate VIS manifold concept is extremely critical so as to accomplish the engine development project c. Serious VIS vibration due to inadequate system concept, which was intended to get the best performance to meet the performance requirement, but not fixable without flow concept change and requiring all DV testing and ECU calibration done again in the end. d. Flow imbalance at part load into each cylinders going over the limit that emission performance dissatisfying the goal. e. Continuous DV test failure due to durability issue, which came from inadequate design concept, intended only to make the best performance during RP phase to win the project. All above are usual failure mode faced during production tooling phase, and all these usually comes with serious engine development project delay and costs huge amount of money to correct or to re develop the manifold followed by performance confirmation, ECU calibration, tool build and DV test. Creating appropriate VIS manifold concept properly in the Page 9 of 10

Engine Performance and Fuel Economy Development with Intake Manifold 01 beginning is extremely critical and all above engineering concerns like performance tuning, tooling, manufacturing, NVH, durability, fuel economy, emission goal, etc must be considered properly during concept phase without failure. Appropriate wave tuning is mandatory to take all these engineering concerns into account concurrently. This way, we can assure no flow path change happening after the design confirmed through performance test and ECU calibration. 7. Conclusion Managed Programs LLC has been working for global OEMs and 1 st Tiers for almost 15 years and found many of them were spending astronomical money and hours for all ECS and CFD analysis without investigating the logical consistency. In an effort to investigate the root causes for the discrepancy, many global OEMs and 1 st tiers are running coupled ECS with CFD analysis to represent more practical behavior of intake manifold. But this tends to take a lot of time and effort to finish it and still most of the analysis is performed without understanding on the details happening inside the intake manifold or inside internal combustion engine, and still it is not regarded as the most accurate and efficient way for the development. To overcome this difficulty, Managed Programs LLC has been developing our proprietary Wave tuning technology for the last 10 years. We have been proactively using this wave tuning technology to support our customers who didn t have experience with engine performance development and didn t develop ECS model like AVL-Boost or GT- Power, or for the 1 st Tiers who were trying to support OEM projects for performance development but without proper 1D ECS simulation support by OEM or even with 1D ECS model. For all recently developed internal combustion engine development projects, Managed Programs LLC made huge success to achieve all performance goals for worldwide global OEMs and for many customers who could not develop or secure their own engine model or even with no engine development experience. Through this technology, Managed Programs LLC could shorten engine performance and intake manifold development period so dramatically that usual RP design iteration numbers until the design get confirmed for performance was reduced from least 3~4 times to 1~ times. Managed Programs LLC has saved a lot of CFD and ECS simulation time and 3D design hours owing to this technology and we were able to reduce all development cost dramatically. Definitions and Abbreviations BMEP : Brake Mean Effective Pressure BSFC : Brake Specific Fuel Consumption CFD : Computational Fluid Dynamics CFM : Cubin Feet per minute CVVL : Continuously Variable Valve Lift Control System CVVT : Continuously Variable Valve Timing Control System DI : Direct Injection ECS : Engine Cycle Simulation FMEP : Frictional Mean Effective Pressure GDI : Gasoline Direct Injection HCCI : Homogeneous Charged Compression Ignition IMEP : Indicated Mean Effective Pressure ISG : Idle Stop-n-Go KERS : Kinetic Energy Recovery System MBT : Maximum Brake Torque NVH : Noise Vibration and Harshness VIS : Variable Induction System AVL-Boost is the Trademark of AVL CFX is the Trademark of ANSYS FLUENT is the Trademark of ANSYS GT-Power is the Trademark of Gamma Technology STAR-CCM+ is the Trademark of CD-Adapco WAVE is the Trademark of Ricardo Contacts: Managed Programs LLC Taehwan Kim (General Manager) Email: tkim@managed-programs.com Add: 436 Giddings Road, Auburn Hills, MI, 4836, USA Tel: (Office) 1-48-977-5314 ext.14 (Mobile) 1-48-95-915 Page 10 of 10