Search Results

Parts, such as bolts, turbine wheels, discs, buckets, and blades, for high strength and oxidation resistance up to 1500 F when suitably heat treated.

The 12 papers in this techncial paper collection represent research in the areas of welding, riveting, joining, and fastening for automotive applications. Papers focus on the recent advances in the process optimization, analytical solution, numerical modeling, response evaluation as well as static and dynamic testing of traditional resistance spot welds, gas metal arc welds, friction stir spot welds, laser welds, rivets, mounts, adhesives, and fasteners.

A combination of laboratory reactor measurements and vehicle FTP testing has been combined to demonstrate a method for diagnosing the formation of NO2 from a diesel oxidation catalyst (DOC). Using small cores from a production DOC and simulated diesel exhaust, the laboratory reactor experiments are used to support a model for DOC chemical reaction kinetics. The model we propose shows that the ability to produce NO2 is chemically linked to the ability of the catalyst to oxidize hydrocarbon (HC). For thermally damaged DOCs, loss of the HC oxidation function is simultaneous with loss of the NO2 production function. Since HC oxidation is the source of heat generated in the DOC under regeneration conditions, we conclude that a diagnostic of the DOC exotherm is able to detect the failure of the DOC to produce NO2. Vehicle emissions data from a 6.6 L Duramax HD pick-up with DOC of various levels of thermal degradation is provided to support the diagnostic concept.

As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA's Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to support a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a ?long pole? in new development efforts. The avionics and software for the Space Shuttle was primarily developed in the 70's and considered state of the art for that time.

A series of flight tests were conducted to design and evaluate a Combined Vision System (CVS) that integrates a forward looking infrared video image with synthetic vision on a primary flight display. System features included colorizing the video image to mesh with the synthetic terrain background, decluttering the approach symbology to facilitate the detection of the approach lights and runway markings, creating a semi-transparent IR sky to ensure continuous situational awareness of the surrounding terrain, and annunciating the decision height to facilitate the transition to the actual runway environment. Over 100 approaches were flown during three flight test sessions. For the first flight test session pilots reviewed early CVS proofs of concept on Honeywell's Citation Sovereign.

The development of PM and NOx reduction system with the combination of DOC included DPF and SCR catalyst in addition to the AOC sub-assembly for NH3 slip protection is described. DPF regeneration strategy and manual regeneration functionality are introduced with using ITH, HCI device on the EUI based EGR, VGT 12.3L diesel engine at the CVS full dilution tunnel test bench. With this system, PM and NOx emission regulation for JPNL was satisfied and DPF regeneration process under steady state condition and transient condition (JE05 mode) were successfully fulfilled. Manual regeneration process was also confirmed and HCI control strategy was validated against the heat loss during transient regeneration mode. Presenter Seung-il Moon

General research in the areas of welding, riveting, joining, and fastening for automotive applications is discussed in the 9 papers in this technical paper collection. Topics include process optimization, analytical solution, numerical modeling, response evaluation as well as static and dynamic testing of traditional resistance spot welds, gas metal arc welds, friction stir spot welds, laser welds, rivets, mounts, adhesives, and fasteners.

The 9 papers in this technical paper collection focus on welding, joining and fastening for automotive applications. Topics covered include adhesively bonded joints, Battelle Structural Stress method, friction stir spot welding, and more. The 9 papers in this technical paper collection focus on welding, joining and fastening for automotive applications. Topics covered include adhesively bonded joints, Battelle Structural Stress method, friction stir spot welding, and more.

This technical paper collection includes papers related to welding and joining of similar or dissimilar materials of plastics, composites, aluminum, magnesium, titanium, and conventional and advanced high strength steels. Papers related to friction stir (spot) welding, ultrasonic welding, resistance welding, arc welding, laser welding, brazing or soldering, riveting and bolting, and adhesive joining, strength, fracture and fatigue of welds, joints and fasteners are covered.

Topics include the effects of fuel and additives on deposit formation, intake system cleanliness, friction, wear, corrosion, and elastomer compatibility. Also covered are effects of fuel specification on drivability, on evaporative emissions, and on the relationship between emissions and drive cycle.

This specification covers a corrosion and heat resistant nickel alloy in the form of sheet, strip, and plate procured in SI (metric) units. AMS 5598 is the inch/pound version of this MAM.

Abstract Joining titanium (Ti) alloys with conventional processes is difficult due to their complex structural properties and ability of phase transformation. Concerning all the difficulties, diffusion bonding is considered as an appropriate process for joining Ti alloys. Ti6Al4V, which is an α+β alloy widely used for aero engine component manufacturing, is diffusion bonded in this investigation. The diffusion bonding process parameters such as bonding temperature, bonding pressure, and holding time were optimized to achieve desired bonding characteristics such as shear strength, bonding strength, bonding ratio, and thickness ratio using response surface methodology (RSM). Empirical relationships were developed for the prediction of the bond characteristics, and sensitivity analysis was performed to determine the increment and decrement tendency of the shear strength with respect to the bonding parameters.

Abstract Electric heavy-duty tractor-trailers (EHDTT) offer an important option to reduce greenhouse gases (GHG) for the transportation sector. However, to increase the range of the EHDTT, this effort investigates critical vehicle design features that demonstrate a gain in overall freight efficiency of the vehicle. Specifically, factors affecting aerodynamics, rolling resistance, and gross vehicle weight are essential to arrive at practical input parameters for a comprehensive numerical model of the EHDTT, developed by the authors in a subsequent paper. For example, drag reduction devices like skirts, deturbulators, vortex generators, covers, and other commercially available apparatuses result in an aggregated coefficient of drag of 0.367. Furthermore, a mixed utilization of single-wide tires and dual tires allows for an optimized trade-off between low rolling resistance tires, traction, and durability.