Technical Paper collections have been re-named for better clarity and alignment.x

Your Selections

Corrosion
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Committees

Events

Magazine

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Use of Nitric Acid to Control the NO2:NOX Ratio Within the Exhaust Composition Transient Operation Laboratory Exhaust Stream

Southwest Research Institute-Robert Henderson, Ryan Hartley, Cary Henry
  • Technical Paper
  • 2020-01-0371
To be published on 2020-04-14 by SAE International in United States
The Exhaust Composition Transient Operation Laboratory (ECTO-Lab) is a burner system developed at Southwest Research Institute (SwRI) for simulation of IC engine exhaust. The current system design requires metering and combustion of nitromethane in conjunction with the primary fuel source as the means of NOX generation. While this method affords highly tunable NOX concentrations even over transient cycles, no method is currently in place for dictating the speciation of nitric oxide (NO) and nitrogen dioxide (NO2) that constitute the NOX mixture. NOX generated through combustion of nitromethane is dominated by NO, and generally results in a NO2:NOX ratio of <5 %. Generation of any appreciable quantities of NO2 is therefore dependent on an oxidation catalyst to oxidize a fraction of the NO to NO2. Presented within this manuscript is a method for precise control of the NO2:NOX ratio within the ECTO-Lab exhaust stream by using nitric acid as the NOX precursor molecule in lieu of nitromethane. While decomposition of nitromethane generates NO as the dominate component of the NOX mixture, nitric acid decomposition produces primarily…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Examination of an on-board hydrogen generator and impact on automotive engine performance.

Aramco-Alexander Voice
Precision Combustion Inc.-Subir Roychoudhury
  • Technical Paper
  • 2020-01-1353
To be published on 2020-04-14 by SAE International in United States
Improvement of brake specific engine emissions and fuel consumption in internal combustion by the introduction of a reducing gas such as hydrogen has been the subject of research in recent years. Approaches include in-cylinder combustion augmentation or as a reductant to facilitate aftertreatment. The primary hurdle to implementing the technique has been the lack of a suitable on-board hydrogen generator for automotive applications. Reforming reactors are well known for converting liquid fuels such as diesel or gasoline into hydrogen or other reducing gas mixtures (synthesis gas). Efficiency and durability for thousands of hours is required for industrial applications for economic viability. Suitability for automotive applications additionally require small size, low cost, fast transient response, fast start up, large turndown, and avoid the need for external water. Reforming via waterless catalytic partial oxidation avoids this shortcoming but is not without its own set of problems. The key challenges are coke avoidance and high hydrogen selectivity. Precision Combustion, Inc. (PCI) has developed a waterless catalytic partial oxidation reformer, for gasoline fuels, suitable for on-board automotive hydrogen generation…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

The influential factors on tire-rocky road interaction under a GPU accelerated code

ESS Engineering Software Steyr-Huaxiang ZHU, Martin Schifko
  • Technical Paper
  • 2020-01-0895
To be published on 2020-04-14 by SAE International in United States
Physical corrosion often happens when vehicles running over the rocky road and bringing up gravels which chip or scratch the car body. The solution to mitigate damage of the car in this situation can only arrive after understanding the influential factors and their significance to the tire-road interaction. Considering the discrete nature of gravel’s behavior, the Discrete Element Method could be a proper tool to reproduce and analyse the scene. In reality, many vehicle and environment parameters could be relevant to the tire-road interaction, such as gravel geometry, surface pattern of the tire, speed of the vehicle and etc. A proper consideration of these elements in the simulation is important before discussing the results. Especially, including geometrical complex objects as rigid bodies in DEM could be challenging under single- and Multi-GPU framework. In this paper, we present an analysis on the interaction between the single tire and rocky road, as the tire confronts gravels with a fixed rotational and translational velocity. Some rock geometrical parameters, different tire surface textures and different loading velocities would be…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Spatially Optimized Diffusion Alloys: A Novel Multi-Layered Steel Material for Exhaust Applications

Arcanum Alloys Inc.-Zachary Detweiler, David Keifer, Daniel Bullard
Tenneco Inc.-Adam Kotrba, Tony Quan, Winston Wei
  • Technical Paper
  • 2020-01-1051
To be published on 2020-04-14 by SAE International in United States
A novel Spatially Optimized Diffusion Alloy (SODA) material has been developed and applied to exhaust systems, a very aggressive environment with high temperatures and loads, as well as excessive corrosion. Traditional stainless steels disperse chromium homogeneously throughout the material, with varying amounts ranging from 11% to 18% dependent upon its grade (e.g. 409, 436, 439, and 441). SODA steels, however, offer layered concentrations of chromium, enabling an increased amount along the outer surface for much needed corrosion resistance and aesthetics. This outer layer, approximately 70µm thick, exceeds 20% of chromium concentration locally, but is only 3% in bulk, offering selective placement of the chromium to minimize its overall usage. And, since this layer is metallurgically bonded, it cannot delaminate or separate from its core, enabling durable protection throughout manufacturing processes and full useful life. The core material may be of various grades, however, so this study employs interstitial free steel (low carbon), which offers not only commercial advantages, but also eases manufacturing operations, as it is more formable than stainless steel grades. The material and…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Thermo-mechanical Fatigue and Life Prediction of Turbocharged Engine Cylinder Head

SAIC Motor Corporation Limited-Zheng Xu
SAIC Motor Technical Center-Yang Jun Wang
  • Technical Paper
  • 2020-01-1163
To be published on 2020-04-14 by SAE International in United States
In order to predict more accurately the cracking failure of cylinder head during the durability test of turbocharged engine in the development, a comprehensive evaluation method of cylinder head durability is established. In this method, both high cycle and low cycle fatigue performance are calculated, and the results are combined statistically using weighted algorithm to provide failure assessment. The method is then applied to investigate the root cause of cracking of cylinder head and assess design optimizations. Multidisciplinary approach is adopted to optimize high cycle fatigue and low cycle fatigue performance simultaneously to achieve the best comprehensive performance. In this paper, the details of the method development are described. First, the high cycle and low cycle fatigue properties of cylinder head materials were measured at different temperatures, and the fatigue life and high temperature creep properties of materials under thermo-mechanical fatigue cycle were also tested. These material properties provide basis for accurate simulations. For the low cycle fatigue analysis model, a thermal shock cycle same as dyno test is simulated using transient method, which accurately…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Interactive Effects between Sheet Steel, Lubricant and Measurement System

General Motors-Jatinder Singh
University of Colorado Denver-Luis Rafael Sanchez Vega, Eduardo Corral
  • Technical Paper
  • 2020-01-0755
To be published on 2020-04-14 by SAE International in United States
This study assessed the interaction between sheet steel, lubricant and measurement system under typical sheet forming conditions. Deep Drawing Quality Bare, Electrogalvanized and Hot Dip Galvanized mild sheet steel, were tested under a Draw Bead Simulator (DBS). Lubricant conditions varied from thoroughly dry (0% lube) to overlubricated (>6 g/m2); with 1g of lubricant per m2 as the target of general usage. Mixed lubrication cases, with incremental amounts of a lubricant applied over an existing base of 1 g/m2 rust protection oil, were analyzed. The results show distinctive differences and similarities on friction between the bare material and the coatings. While friction on the bare substrate was higher than the coatings under lubricated conditions, it was significantly more tolerant to dry conditions. Stick-slip behavior was studied as a measurement system response to intermittent friction between the testing tools. These measurement test responses, and sheet surface texture changes during testing were discussed.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Microstructure-Fatigue Property Relationships for Cast Irons

National Research Council-Xijia Wu
  • Technical Paper
  • 2020-01-0187
To be published on 2020-04-14 by SAE International in United States
Cast irons are widely used for combustion engine/exhaust system applications, not only because they are less expensive but also because they offer some attractive properties such as good thermal conductivity, relatively high specific yield strength, and good oxidation resistance. Cast irons can be made with a wide variety of microstructures containing either flake-like graphite (FG), nodular graphite (NG) or vermicular graphite (VG), or mixing of the above, which control their mechanical and fatigue properties. In this paper, a microstructure-fatigue property relationship model is developed, combining the Tanaka-Mura-Wu’s fatigue crack nucleation model with Eshelby’s solution for materials containing ellipsoidal inclusions. This applies to cast irons considering its microstructural graphite characters (shape, size, elastic modulus and Poisson’s ratio). This model is used to analyse ductile cast iron (DCI) with nodular graphite (NG) microstructure, grey cast iron (GCI) with flake-like graphite (FG) microstructure, and compacted graphite iron (CGI) with vermicular graphite (VG) microstructure. Excellent agreement is found between the model prediction and the experimental data or the Coffin-Manson-Basquin correlations at room temperature. Further development will be to incorporate…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Crevice Corrosion Accelerated Test for Cylinder Head/Gasket/Monoblock Assemblies from Lightweight Engines Exposed to Overheating Cycles

Instituto Politecnico Nacional Esime Zac-Gerardo Rodríguez-Bravo, Roberto Vega-Moron
Instituto Politécnico Nacional ESIQIE-Jesús Godínez-Salcedo
  • Technical Paper
  • 2020-01-1067
To be published on 2020-04-14 by SAE International in United States
Severe crevice corrosion occurring at the joint of cylinder head/gasket/mono-block from lightweight engines causes accelerated dissolution of lightweight material, in particular, in cylinder head producing the linking of the cooling vessels with the combustion chambers or oil vessels. It is conductive to combustion of coolant or oil, and contamination of oil with coolant or vice versa, which is considered as catastrophic engine failure. Since crevice corrosion is dependent of many of the actual assembly characteristics, coolant and engine operation conditions, full-scale tests are the most frequent alternative for this type of evaluations. Nonetheless, they are very long and expensive, and sometimes, unreliable tests. Alternatively, the standard procedure ASTM-G78 is widely used to evaluate crevice corrosion propensity of different metallic materials under certain specified conditions trough immersion tests in a corrosive media in shorter test times. However, the method does not cover the characteristics and conditions existing at the cylinder head/gasket/mono-block joint. Hence, this paper presents an accelerated test consisting on three-electrode cyclic potentiodynamic anodic polarization and polarization resistance standard trials using special assembly samples to…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

The role of NOx in engine lubricant oxidation

Infineum UK, Ltd.-David R. Coultas
  • Technical Paper
  • 2020-01-1427
To be published on 2020-04-14 by SAE International in United States
Engine technology trends like downsizing, direct injection and effective lean NOx aftertreatment have created challenging environments for lubricating oils. Longer contact times of the lubricant with fuel and NOx, higher sump temperatures and higher NOx levels in blow-by gas promote nitration-oxidation driven by the action of NOx and air on hydrocarbons. Nitration-oxidation has often been overlooked as a mechanism of oil oxidation in real world engines. Indeed, the emphasis is almost exclusively on iron catalysed oxidation in bench tests purporting to protect modern engines against lubricant oxidation. This paper will demonstrate that a proprietary bench nitration-oxidation test is capable of reproducing trends in nitrate ester formation and consumption seen in real engines, which also fully explain the resulting impact on lubricant oxidation without the use of iron catalysts.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Development of a novel method to simulate cavity preservation in automotive industry

ESS Engineering Software Steyr-Martin Schifko, Kevin Verma, Muraleekrishnan Menon, Vishal NAIR, Ravi Kanth Borra
ESS Gmbh-Bhargav Krishna Chitneedi
  • Technical Paper
  • 2020-01-0900
To be published on 2020-04-14 by SAE International in United States
Corrosion protection is a major topic of research for automotive manufacturers and major suppliers. The most critical parts affected by corrosion are the pillars and cavities. Automotive manufacturers spend a lot of effort to improve protection layers as much as possible to increase the longevity of their products. The Electro-Coat Paint Operation (ELPO) or E-Coat process is key in achieving this goal. Unfortunately, often the electric current does not reach all the areas very well and resulting in undercoating. Also, the consequent baking process might see the ovens not achieving the desired temperatures into the cavities. As a fact it often happens that these areas are exposed by undercoating, and hence undermining the quality of corrosion protection. Some car manufacturers investigate one level more to assure a good quality of corrosion protection also within cavities, by applying wax. This wax coating process aims to cover all problematic areas in a way to make cavities more resistant to unfriendly conditions such as rain, snow, and salt. At present, waxing solves those problems quite well. However, wax…