Search Results (144)

Technical paper covering emission drivers 2015 through 2017, background on the CO2 challenge, Diesel and Gasoline technologies as well as enablers for hybridisation.

Abstract: Up to now, the demand for high specific power and torque was the main driver for boosting the engine. Over the years, it also led to significant fuel benefits within emission cycle measurements. On the other hand high boosted engines come with well-known drawbacks, which are still the main driver for turbocharger development today: • Slower transient performance compared to naturally aspirated • Necessity of fuel enrichment to protect the turbocharger’s components for higher engine speeds. These two points need to be addressed by an evolution of boosting systems combined with a Miller cycle for a high efficiency combustion process. The presented paper shows the effects of Miller valve timings on the engine performance and figures out the synergies with a VNT turbine. Garrett (Honeywell Transportation Systems) presents a VNT turbine optimized for gasoline engines and the capability for exhaust temperatures up to 950° C. This optimized design overcomes several well-known failure modes leading to a gasoline VNT for mass production. Within this paper 1D engine process simulations are carried out for a 1.5 l 3-cylinder gasoline engine. The high Miller rate even at full load enable to increase the compression ratio. High Miller ratios require an increase in boost pressure which can provided by the latest Garrett compressors design for these applications. The reduced engine backpressure caused by the VNT turbine in combination with the higher achievable Miller ratio lead to a reduced fuel consumption at rated power of 11 %. One of the challenges for Miller application is the transient engine response which is typically worse compared to conventional boosted engines and therefore not acceptable for the customer. Here the VNT turbine shows a reduced Time-To-Torque at 1500 rpm of 48 % compared to a wastegate turbine with otherwise unchanged boundary conditions. Summarizing, the combination of a VNT turbine which provides high turbine power and a Miller engine concept which requires high boost pressures is a good concept to reduce the fuel consumption for future gasoline engines. Keywords: Miller, VNT, VTG, engine matching, gasoline engine

What it does: This technology uses movable “gates” or “vanes” inside the turbocharger to better regulate airflow to precisely match the needs of the engine across engine speeds. This results in improved fuel economy and reduced CO2 emissions at nearly all engine speeds. Why it’s innovative: It solves for the inherently higher temperatures associated with gasoline engines by adapting the variable geometry technology for modern gasoline engines that has been synonymous with diesel engines for nearly three decades. Garrett (Honeywell Transportation) and VW launched the first gas VNT engine in a cost-effective manner suited for high-volume production vehicles with best-in-class fuel economy.

1. Why Combine Miller + VNT Turbo ? Miller Cycle Combustion Benefits Variable Nozzle Turbine, VNT Turbochargers 2. Specific Developments for Gasoline Aerodynamics Reliability Increased CR & Miller Cycle brings BSFC and T3 reduction but needs higher boost Option to compress in the cylinder when its efficient to do so or in the Turbo (work split) VNT Turbo gives flat Turbine efficiency, enabling lower Turbine inlet pressure P3 for ISO Power Charge Air Cooling needs to be increased to keep the same engine inlet temperature First high volume VNT for Gasoline. Specific Aero & Materials, Classic Design & Std Clearances Full portfolio of VNT Gas under development for 1,0L to 2,0L

VNT Turbo for Gasoline Miller Engine • Why Combining Miller + VNT Turbo ? - Miller Cycle Combustion Benefits - Variable Nozzle Turbine, VNTTM Turbochargers • Specific VNT Developments for Gasoline - Aerodynamics - Reliability Summary • Garrett first high volume Gas VNT + Miller cycle with SOP in end 2016 • Specific aerodynamics developed to meet gas engine flow requirements • Design & Qualification plan complete for 880°C and in progress for 950°C • Full portfolio of VNT Gas being developed to cover 1.0L to 2.0L LEARN MORE

Conclusion • Options exist to further enhance Diesel Performance • Traded for affordable and saleable NOx reduction • As such Boosting can play a significant role reaching RDE • Other Engine and After-treatment systems must improve too • Advanced Control offers further opportunities too • Need to get the BEST out of a given Hardware Set • OnRAMPTM multi-variable control TOOL Suite holistic approach learn more READ MORE

The development of heavy duty engines is driven by customer as well as legal demands. To find the best compromise between low gaseous and particulate emissions with lowest fuel consumption and high reliability MAN Truck & Bus in cooperation with Honeywell developed a Two Stage turbo charging system for the D26 launched in 2009. This paper describes the evolution of the D26 engine up to the present challenging emission legislation. The benefits of a Two Stage system compared to a Single Stage are discussed. Finally a detailed description of the turbo charger development such as matching challenges, aero selection and test bench work as well as special features of the latest evolution are part of the paper.

As real driving emissions and CO2 regulations grow, turbo gasoline engines are winning customer praise the world over for being fun to drive while achieving high fuel economy. In response, Garrett has developed the 3rd generation gasoline turbo. learn more

This paper highlights the steps that have been taken to improve the design, analysis, measurement and verification of HCF in vane less turbine stages, the intent being to improve both the HCF robustness and maintain performance. In making these improvements the impact on the aerodynamic performance of the turbine stages was also strongly considered to ensure that improvements made for HCF were not made at the expense of performance. The investigation of these new design options required developments in analytical capabilities, specifically 3D unsteady CFD, in order to make the necessary iterations with adequate fidelity in a practical timeframe. To verify the analysis techniques comprehensive experimental measurement of blade strain levels across multiple designs was also conducted and the results compared with analysis. Finally endurance testing was conducted to confirm that the measured improvements in HCF resulted in longer (and sufficient) service life of the turbine stage. Estimation of the required service life was accomplished using the process presented by Kulkarni et al (IMechE 2010).

Honeywell Transportation Systems has collaborated on an ultra-high efficiency two stage serial turbocharger system under the European Union FP7 GA-2012 CORE project. The compressors of both the low pressure and high pressure turbochargers were design optimized for the highly specific operating conditions of two stage boosting. The high pressure turbine is characterized by a sector divided fixed vane nozzle, while the low pressure turbine stage features an axial turbine wheel. The two turbines were designed specifically to achieve highest possible efficiency while minimizing ducting losses between the two stages. The end result is a novel high performance boosting system that fits in a unique package. This paper describes the approach used to set design targets for each stage of the two stage turbocharger system. The design approach used to meet these targets will be presented, and test results from gas stand will be shown measured against performance targets and performance predictions.

While engine boundary conditions have become harsher, fine, accurate and sustainable control of boost is challenging the way mechatronics components are engineered. This paper describes key elements of the kinematic tools developed by Honeywell Turbocharger Technologies in order to optimize turbocharger control solutions. It includes details on CAE applications such as fluid dynamics, flexible multi-body dynamics and thermo-mechanical simulations and how they can be linked together to analyse a complete system.