Steady Modeling of a Turbocharger Turbine for Automotive Engines

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Fabio Bozza ◽  
Vincenzo De Bellis
Keyword(s):  
Combustion Engine ◽  
Numerical Procedure ◽  
Engine Performance ◽  
Operating Conditions ◽  
Flow Equations ◽  
Automotive Engine ◽  
1D Modeling ◽  
Variable Geometry Turbine ◽  
Geometrical Data ◽  
Actual Operation

Nowadays the turbocharging technique is playing a fundamental role in improving automotive engine performance and reducing fuel consumption and the exhaust emissions, in spark-ignition and compression ignition engines, as well. To this end, one-dimensional (1D) modeling is usually employed to compute the engine-turbocharger matching, to select the boost level in different operating conditions, and to estimate the low-end torque level and the transient response. However, 1D modeling of a turbocharged engine requires the availability of the turbine and compressor characteristic maps. This leads to some typical drawbacks: (1)Performance maps of the turbocharger device are usually limited to a reduced number of rotational speeds, pressure ratios, and mass flow rates because of turbine/compressor matching limits; (2) as a consequence of previous issue, unphysical extrapolation of maps' data is commonly required; and (3) heat transfer conditions may strongly differ between test bench measurements and actual operation, where turbocharger is coupled to an internal combustion engine. To overcome the above problems, in the present paper a numerical procedure is introduced: It solves 1D steady flow equations inside the turbine components with the aim of accurately reproducing the experimentally derived characteristic maps. The steady procedure describes the main phenomena and losses arising within the stationary and rotating channels constituting the turbine. It is utilized to directly compute the related steady maps, starting from the specification of a reduced set of geometrical data. An optimization process is employed to identify a number of tuning constants included in the various loss correlations. The procedure is applied to the simulation of five different turbines: three waste-gated turbines, a twin-entry turbine, and a variable geometry turbine. The numerical results show good agreement with the experimentally derived maps for all the tested devices. The model is, hence, used to evaluate the turbine performance in the whole operating domain.

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.

scholarly journals Mission Performance Simulation of Integrated Helicopter–Engine Systems Using an Aeroelastic Rotor Model

2013 ◽  
Vol 135 (9) ◽  
Author(s):  
Ioannis Goulos ◽  
Panagiotis Giannakakis ◽  
Vassilios Pachidis ◽  
Pericles Pilidis
Keyword(s):  
Fuel Consumption ◽  
Three Dimensional ◽  
Numerical Procedure ◽  
Engine Performance ◽  
Flight Dynamics ◽  
Flight Test ◽  
Integrated Approach ◽  
Operating Conditions ◽  
Main Rotor ◽  
Engine Systems

This paper presents an integrated approach, targeting the comprehensive assessment of combined helicopter engine designs within designated operations. The developed methodology comprises a series of individual modeling theories, each applicable to a different aspect of helicopter flight dynamics and performance. These relate to rotor blade modal analysis, three-dimensional flight path definition, flight dynamics trim solution, aeroelasticity, and engine performance. The individual mathematical models are elaborately integrated within a numerical procedure, solving for the total mission fuel consumption. The overall simulation framework is applied to the performance analysis of the Aérospatiale SA330 helicopter within two generic, twin-engine medium helicopter missions. An extensive comparison with flight test data on main rotor trim controls, power requirements, and unsteady blade structural loads is presented. It is shown that, for the typical range of operating conditions encountered by modern twin-engine medium civil helicopters, the effect of operational altitude on fuel consumption is predominantly influenced by the corresponding effects induced on the engine rather than on airframe rotor performance. The implications associated with the implicit coupling between aircraft and engine performance are discussed in the context of mission analysis. The potential to comprehensively evaluate integrated helicopter engine systems within complete three-dimensional operations using modeling fidelity designated for main rotor design applications is demonstrated. The proposed method essentially constitutes an enabler in terms of focusing the rotorcraft design process on designated operation types rather than on specific sets of flight conditions.

scholarly journals Mission Performance Simulation of Integrated Helicopter–Engine Systems Using an Aeroelastic Rotor Model

2013 ◽  
Author(s):  
Ioannis Goulos ◽  
Panos Giannakakis ◽  
Vassilios Pachidis ◽  
Pericles Pilidis
Keyword(s):  
Fuel Consumption ◽  
Three Dimensional ◽  
Numerical Procedure ◽  
Engine Performance ◽  
Flight Dynamics ◽  
Flight Test ◽  
Integrated Approach ◽  
Operating Conditions ◽  
Main Rotor ◽  
Engine Systems

This paper presents an integrated approach, targeting the comprehensive assessment of combined helicopter–engine designs, within designated operations. The developed methodology comprises a series of individual modeling theories, each applicable to a different aspect of helicopter flight dynamics and performance. These relate to rotor blade modal analysis, three-dimensional flight path definition, flight dynamics trim solution, aeroelasticity and engine performance. The individual mathematical models are elaborately integrated within a numerical procedure, solving for the total mission fuel consumption. The overall simulation framework is applied to the performance analysis of the Aérospatiale SA330 helicopter within two generic, twin-engine medium helicopter missions. An extensive comparison with flight test data on main rotor trim controls, power requirements and unsteady blade structural loads is presented. It is shown that, for the typical range of operating conditions encountered by modern twin-engine medium civil helicopters, the effect of operational altitude on fuel consumption is predominantly influenced by the corresponding effects induced on the engine, rather than on airframe–rotor performance. The implications associated with the implicit coupling between aircraft and engine performance, are discussed in the context of mission analysis. The potential to comprehensively evaluate integrated helicopter–engine systems within complete three-dimensional operations, using modeling fidelity designated for main rotor design applications, is demonstrated. The proposed method essentially constitutes an enabler in terms of focusing the rotorcraft design process on designated operation types, rather than on specific sets of flight conditions.

scholarly journals Numerical Simulation of Two-Stage Variable Geometry Turbine

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5349
Author(s):  
Dariusz Kozak ◽  
Paweł Mazuro ◽  
Andrzej Teodorczyk
Keyword(s):  
Combustion Engine ◽  
Three Dimensional ◽  
High Load ◽  
Operating Conditions ◽  
Two Stage ◽  
Variable Turbine Geometry ◽  
Low Load ◽  
Variable Geometry Turbine ◽  
Stage System ◽  
Maintenance Requirements

The modern internal combustion engine (ICE) has to meet several requirements. It has to be reliable with the reduced emission of pollutant gasses and low maintenance requirements. What is more, it has to be efficient both at low-load and high-load operating conditions. For this purpose, a variable turbine geometry (VTG) turbocharger is used to provide proper engine acceleration of exhaust gases at low-load operating conditions. Such a solution is also efficient at high-load engine operating conditions. In this paper, the result of an unsteady, three-dimensional (3D) simulation of the variable two-stage turbine system is discussed. Three different VTG positions were considered for those simulations, along with three different turbine speeds. The turbine inlet was modeled as six equally placed exhaust pipes for each cylinder to eliminate the interference of pressure waves. The flow field at the outlet of the 1st stage nozzle vane and 2nd stage rotor was investigated. The simulations showed that the variable technologies significantly improve the efficiency of the two-stage turbine system. The highest overall efficiency of the two-stage system was achieved at 60,000 rpm and 11o VTG position.

Parametric Study on Ported Shroud Locations and Geometries for a Turbocharger Compressor

2019 ◽  
Author(s):  
Suheab Thamizullah ◽  
Abdul Nassar ◽  
Antonio Davis ◽  
Gaurav Giri ◽  
Leonid Moroz
Keyword(s):  
Centrifugal Compressor ◽  
Combustion Engine ◽  
Engine Performance ◽  
Operating Conditions ◽  
Entire Study ◽  
Operating Condition ◽  
Baseline Design ◽  
Operating Range ◽  
Ported Shroud ◽  
The Impact

Abstract Turbochargers are commonly used in automotive engines to increase the internal combustion engine performance during off-design operating conditions. When used, the widest operating range for the turbocharger is desired, which is limited on the compressor side by the choke condition and the surge phenomenon. The ported shroud technology is used to extend the operable working range of the compressor, by permitting flow disturbances that block the blade passage to escape and stream back through the shroud cavity to the compressor inlet. The impact of this technology, on a speed-line, at near optimal operating condition, near choke operating condition and near surge operating condition is investigated. The ported shroud (PS) self-recirculating casing treatment is widely used to delay the onset of surge by enhancing the aerodynamic stability of the turbocharger compressor. While the ported shroud design delays surge, it usually comes with a small penalty in efficiency. This research involves designing a single-stage centrifugal compressor for the given specifications, considering the application of an automotive turbocharger. The ported shroud was then introduced in the centrifugal compressor. The performance characteristics were obtained, both at the design and at off-design conditions, both with and without the ported shroud. The performance was compared at various off-design operating speed lines. The entire study, from designing the compressor to optimizing the ported shroud configuration, was performed using the commercial AxSTREAM® software platform. Parametric studies were performed to study the effect of ported shroud axial location along the blade axial length on the operating range and performance. The baseline design, without the ported shroud (P0), and the final geometry with it for all PS inlet axial locations (P1 to P5) were analysed using a commercial CFD package and the results were compared with those from the streamline solver.

scholarly journals Investigations of Exhaust Emissions from a Combustion Engine under Simulated Actual Operating Conditions in Real Driving Emissions Test

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 935
Author(s):  
Monika Andrych-Zalewska ◽  
Zdzislaw Chlopek ◽  
Jerzy Merkisz ◽  
Jacek Pielecha
Keyword(s):  
Emission Intensity ◽  
Combustion Engine ◽  
Exhaust Emissions ◽  
Operating Conditions ◽  
Motor Vehicles ◽  
Exhaust Emission ◽  
Vehicle Speed ◽  
Urban Rural ◽  
Actual Operation ◽  
Specific Distance

The paper describes the methodology of research of exhaust emissions from a combustion engine under engine states determined by the vehicle actual operation in the RDE test. The processes of quantities determining the vehicle motion and engine states have been recorded, along with the exhaust emission intensity. Based on the developed research methodology, zero-dimensional characteristics of the processes of the emission intensity have been determined under the conditions of urban, rural and motorway traffic, as well as in the entire test. The authors also determined the average specific distance exhaust emissions under the conditions of urban, rural and motorway traffic, as well as in the entire test. Based on the above results, the unique characteristics of the relation of the average specific distance emissions and the average vehicle speed have been obtained. The obtained characteristics may be used in the modeling of exhaust emissions from motor vehicles under actual traffic conditions. The authors also explored the sensitivity of the average specific distance emissions to the vehicle driving style.

scholarly journals CFD Performance Analysis of a Spark Ignition Engine Fueled by Landfill Gas

2014 ◽  
Vol 7 (1) ◽  
pp. 26-33
Author(s):  
Daniel Swain ◽  
S.O. Bade Shrestha
Keyword(s):  
Greenhouse Gas Emission ◽  
Combustion Engine ◽  
Fluid Dynamic ◽  
Fuel Efficiency ◽  
Landfill Gas ◽  
Flame Temperature ◽  
Engine Performance ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Pure Methane

Landfill gas (LFG) that is generated in an anaerobic environment in landfills and consists primarily of methane and carbondioxide with small amount of nitrogen and other non-methane gases, could be collected and used to produce energy either by extracting methane or using the landfill gas directly in an internal combustion engine or a gas turbine. It amounts to be a net-negative greenhouse gas emission process. Carbondioxide component of LFG dilutes the fuel and absorbs some of the heat of combustion, causing reduced flame temperature that decreases NOx emissions and also suppresses knock. A model was developed and validated with the experimental data available in literature, using the computation fluid dynamic (CFD) code, KIVA-4. Various engine performance parameters at various operating conditions were evaluated and the benefits of methane purification and or direct use of LFG as a fuel in the engine scenarios were compared. It was found that landfill gas used directly at higher compression ratios can be used for pure methane fuel with higher fuel efficiency than can be achieved using pure methane fuel only.

Numerical Calibration of Diesel Engine Variable Valve Timing

2012 ◽  
Vol 516-517 ◽  
pp. 628-633
Author(s):  
Sheng Ou Hu ◽  
Ren Xian Li
Keyword(s):  
Diesel Engine ◽  
Working Conditions ◽  
Combustion Engine ◽  
Engine Performance ◽  
Simulation Method ◽  
Calibration Method ◽  
Operating Conditions ◽  
Variable Valve Timing ◽  
Valve Timing ◽  
Variable Valve

The performance of internal combustion engine can be improved by using variable valve timing technology. but how to get the optimal inlet/export valve open or close angles under various operating conditions still relies mainly on testing calibration method. By means of one-dimensional working process simulation method, the performance of a four cylinder diesel engine was simulated, and the influences of diffrent inlet/export valve timing on engine performances were compared. Optimum valve timing values and engine performances under thirty kinds of working conditions were gotton. After that, the engine performances compared with that without variable valve timing. Simulation results show that the engine performance, especially the emission performance, can be improved at all simulation working conditions. The method used in this paper may be a new way for calibration of optimal valve timing.

Performance Analysis of an Electric Turbocompounding System for a Hybrid Vehicle Diesel Engine

2015 ◽  
Author(s):  
Zhanming Ding ◽  
Weilin Zhuge ◽  
Yangjun Zhang ◽  
Yong Yin ◽  
Shuyong Zhang
Keyword(s):  
Diesel Engine ◽  
Waste Heat ◽  
Combustion Engine ◽  
Control Strategies ◽  
Full Range ◽  
Engine Performance ◽  
Driving Cycle ◽  
Operating Conditions ◽  
Full Load ◽  
Power Turbine

Waste heat recovery (WHR) is one of the main approaches to improve the internal combustion engine (ICE) overall efficiency and reduce emissions. The electric turbocompounding (ETC) technology is considered as a promising WHR technology for vehicle engines due to its compactness and light weight. In order to improve the overall fuel efficiency of the engine at practical operating conditions, the impacts of the implementation of the ETC system should be investigated not only at engine full load conditions, but also under practical driving cycles. In this paper, an ETC system was designed for a 4.75 L diesel engine, in which a power turbine was installed down-stream to the turbocharger turbine. A performance simulation model of the ETC engine was developed on the basis of the diesel engine model, which was validated against engine performance experimental data. The control strategies of the wastegate of turbocharger turbine, the wastegate of power turbine and the operating torque of generator were determined. The relative variation in BSFC was studied under full range of operating conditions, and results show that the maximum improvement of fuel economy is 6.7% at an engine speed of 1000 rpm and 70% of full load, in comparison with the baseline diesel engine. Main factors lead to the performance differences between the ETC engine and the baseline engine were analyzed. Furthermore, the performance of the ETC engine under the C-WTVC driving cycle was investigated. Results show that the implementation of the ETC system resulted in a 1.2% fuel consumption reduction under the C-WTVC driving cycle.

Performance and Emissions Characteristics Investigation of a Bi-Fuel SI Engine Fuelled by CNG and Gasoline

2006 ◽  
Author(s):  
Abazar Shamekhi ◽  
Nima Khatibzadeh ◽  
Amir H. Shamekhi
Keyword(s):  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Engine Performance ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Engine Fuel ◽  
Wide Range ◽  
Performance And Emissions ◽  
Pollutant Sources

Nowadays, increased attention has been focused on internal combustion engine fuels. Regarding environmental effects of internal combustion engines particularly as pollutant sources and depletion of fossil fuel resources, compressed natural gas (CNG) has been introduced as an effective alternative to gasoline and diesel fuel in many applications. A high research octane number allows combustion at higher compression ratios without knocking and good emission characteristics of HC and CO are major benefits of CNG as an engine fuel. In this paper, CNG as an alternative fuel in a spark ignition engine has been considered. Engine performance and exhaust emissions have been experimentally studied for CNG and gasoline in a wide range of the engine operating conditions.

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