Potential of Water Injection for Gasoline Engines by Means of a 3D-CFD Virtual Test Bench

2021 ◽  
Author(s):  
Antonino Vacca
Keyword(s):  
Test Bench ◽  
Water Injection ◽  
Gasoline Engines ◽  
Virtual Test

Potential of Direct Water Injection to Reduce Knocking and Increase the Efficiency of Gasoline Engines

2017 ◽  
pp. 338-359 ◽  
Author(s):  
Matthias Hunger ◽  
Tobias Böcking ◽  
Ulrich Walther ◽  
Michael Günther ◽  
Normann Freisinger ◽  
...  
Keyword(s):  
Water Injection ◽  
Gasoline Engines ◽  
Direct Water Injection

scholarly journals A virtual test bench for determining the loads in the air suspension of the rear trolley of a truck at the early stages of design

2021 ◽  
Vol 1 (3) ◽  
pp. 76-86
Author(s):  
R.O. Maksimov ◽  
◽  
I.V. Chichekin ◽  
Keyword(s):  
Mathematical Model ◽  
Test Bench ◽  
Software Tools ◽  
Rigid Bodies ◽  
Virtual Test ◽  
Early Stages ◽  
Air Suspension ◽  
Solid Suspension ◽  
Suspension Model ◽  
Standard Software

To determine the maximum loads acting in the rear air suspension of a truck at the early stages of design there was used computer modeling based on solving equations of dynamics of solids and implemented in the Recurdyn software. The components of the developed virtual test bench, includ-ing hinges, power connections, drive axles, a wheel-hub assembly with a wheel and a support plat-form, are considered in detail. The test bench is controlled using a mathematical model created in the environment for calculating the dynamics of rigid bodies and associated with a solid suspension model by standard software tools of the application. The test bench is controlled using a mathemati-cal model created in the environment for calculating the dynamics of rigid bodies and associated with a solid suspension model by standard software tools of the application. The use of such a test bench makes it possible to determine the loads in the hinges and power connections of the suspen-sion, to determine the mutual positions of the links for each load mode, to increase the accuracy of the calculation of loads in comparison with the flat kinematic and force calculation. The mathemati-cal model of the virtual test bench allows to carry out numerous parametric studies of the suspension without the involvement of expensive full-scale prototypes. This makes it possible at the early stages of design to determine all hazardous modes, select rational parameters of the elements, and reduce design costs. The paper shows the results of modeling the operation of a virtual test bench with an air suspen-sion in the most typical loading modes, identifying the most dangerous modes. The efficiency and adequacy of the mathematical model of the suspension was proved. Examples of determining the force in all the joints of the structure, the choice of maximum loads for design calculations when designing the air suspension of vehicle were shown.

Water injection for gasoline engines – potentials and challenges

2019 ◽  
pp. 115-138
Author(s):  
Ingo Hermann ◽  
Claus Glahn ◽  
Martin Paroll ◽  
Werner Gumprich
Keyword(s):  
Water Injection ◽  
Gasoline Engines

scholarly journals Numerical Investigation of a Wood-Chip Downdraft Gasifier

2019 ◽  
Vol 113 ◽  
pp. 01002
Author(s):  
Alessandro Vulpio ◽  
Nicola Casari ◽  
Mirko Morini ◽  
Michele Pinelli ◽  
Alessio Suman
Keyword(s):  
Numerical Model ◽  
Test Bench ◽  
Wood Chip ◽  
Biomass Gasification ◽  
Careful Analysis ◽  
Good Match ◽  
Energy Field ◽  
Downdraft Gasifier ◽  
Virtual Test ◽  
Working Parameters

Biomass gasification is regarded as one of the most promising technology in the renewable energy field. The outcome of such operation, i.e. the synfuel, can be exploited in several ways, for example powering engines and turbines, and is considered more flexible than the biomass itself. For this reason, a careful analysis of the gasification performance is of paramount importance for the optimization of the process. One of the techniques that can be used for such a purpose, is the numerical analysis. CFD is indeed a tool that can be of great help in the design and study of the operation of the gasifier, allowing for an accurate prediction of the operating parameters. In this work, a downdraft gasifier is considered, and the biomass is made of wood chip. The present analysis is devoted to build the numerical model and simulate all the reactions that happen inside an actual gasifier, considering the drying of the wood chip, heating, pyrolysis, and combustion. Good match with experimental results is found, making the numerical model here presented a reliable virtual test bench where investigating the effects of variation in the working parameters.

scholarly journals On-Line Open-Phase Fault Detection Method for Switched Reluctance Motors with Bus Current Measurement

Actuators ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 117
Author(s):  
Alejandra de la Guerra ◽  
Victor M. Jimenez-Mondragon ◽  
Lizeth Torres ◽  
Rafael Escarela-Perez ◽  
Juan C. Olivares-Galvan
Keyword(s):  
Test Bench ◽  
Angular Position ◽  
Current Measurement ◽  
Switched Reluctance Motors ◽  
Switched Reluctance ◽  
Virtual Test ◽  
Open Phase ◽  
On Line ◽  
Different Sources ◽  
A Current

This article introduces an on-line fault diagnosis (FD) system to detect and recognize open-phase faults in switched reluctance motors (SRMs). Both tasks, detection and recognition, are based on functions built with the same information but from different sources. Specifically, these functions are constructed from bus current measurement provided by a sensor and from the estimate of such a current provided by an extended Kalman filter (EKF) that performs the estimation from only rotor angular position measurements. In short, the FD system only requires two measurements for employment: bus current and angular position. In order to show its efficacy, results from numerical simulations (performed in a virtual test bench) are presented. Specifically, these simulations involve the dynamics of the SRM, including the magnetic phenomena caused by the analyzed faults. The motor dynamics were obtained with finite element simulations, which guarantee results close to the actual ones.

Effects of Ambient Air Humidity on Emissions and Efficiency of Large-Bore Lean-Burn Otto Gas Engines in Development and Application

2020 ◽  
Author(s):  
Tomas Bartkowski ◽  
Stefan Eicheldinger ◽  
Maximilian Prager ◽  
Georg Wachtmeister
Keyword(s):  
Air Conditioning ◽  
Test Bench ◽  
Water Injection ◽  
Measurement Data ◽  
Ambient Air ◽  
Injection System ◽  
Nox Emissions ◽  
Air Humidity ◽  
Ambient Conditions ◽  
Lean Burn

Abstract The use of large-bore Otto gas engines is currently spreading widely considering the growing share of Power-To-Gas (P2G) solutions using renewable energies. P2G with a Combined Heat and Power (CHP) plant offers a promising way of utilizing chemical energy storage to provide buffering for volatile energy sources such as wind and solar power all over the world. Therefore, ambient conditions like air temperature, humidity and pressure can differ greatly between the location and time of engine operation, influencing its performance. Especially lean-burn Otto processes are sensitive to changes in ambient conditions. Besides, targeted use of humidity variation (e.g. through water injection in the charge air or combustion chamber) can help to reduce NOx emissions at the cost of a slightly lower efficiency in gas engines, being an alternative to selective catalytic reduction (SCR) exhaust gas aftertreatment. The ambient air condition boundaries have to be considered already in the early stages of combustion development, as they can also have a significant effect on generated measurement data in combustion research. To investigate the behavior, a test bench with a natural gas (CNG) powered single-cylinder research engine (piston displacement 4.77 1) at the Institute of Internal Combustion Engines (LVK) of the Technical University of Munich (TUM) was equipped with a sophisticated charge air conditioning system. This includes an air compressor and refrigeration dryer, followed by temperature and pressure control, as well as a controlled injection system for saturated steam and homogenizing containers, enabling the test bench to precisely emulate a widespread area of charge air parameters in terms of pressure, temperature and humidity. With this setup, different engine tests were conducted, monitoring and evaluating the engine’s emission and efficiency behavior regarding charge air humidity. In a first approach, the engine was operated maintaining a steady air-fuel equivalence ratio λ, fuel energy input (Q̇fuel = const.) and center of combustion (MFB 50%) while the relative ambient humidity was varied in steps between 21% and 97% (at 22 °C and 1013.25 hPa). Results show a significant decrease in nitrogen oxides (NOx) emissions (−39.5%) and a slight decrease in indicated efficiency (−1,9%) while hydrocarbon (THC) emissions increased by around 60%. The generated data shows the high significance of considering charge air conditioning already in the development stage at the engine test bench. The comparability of measurement data depends greatly on ambient air humidity. In a second approach, the engine was operated at a constant load and constant NOx emissions, while again varying the charge air humidity. This situation rather reflects an actual engine behavior at a CHP plant, where today often NOx–driven engine control is used, maintaining constant NOx emissions. The decrease in indicated efficiency was comparable to the prior measurements, while the THC emissions showed only a mild increase (5%). From the generated data it is, for instance, possible to derive operational strategies to compensate for changes in ambient conditions while maintaining emission regulations as well as high-efficiency output. Furthermore, the results suggest possibilities, but also challenges of utilizing artificial humidification (e.g. through water injection) considering the effects on THC emissions and efficiency. A possible shift of the knocking limit to earlier centers of combustion with higher humidity is to be investigated. The main goal is the further decrease of NOx emissions, increase of efficiency, while still maintaining hydrocarbon emissions.

Potentials of cooled EGR and water injection for knock resistance and fuel consumption improvements of gasoline engines

2016 ◽  
Vol 169 ◽  
pp. 112-125 ◽  
Author(s):  
Fabio Bozza ◽  
Vincenzo De Bellis ◽  
Luigi Teodosio
Keyword(s):  
Fuel Consumption ◽  
Water Injection ◽  
Gasoline Engines
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