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2014-10-16
WIP Standard
AS25050B
This specification covers the chromaticity and transmission requirements of equipment light transmitting ware in the descending order of transmission. It is intended for use in military aircraft lighting.
2014-10-15
WIP Standard
AS85731/1B
No scope available.
2014-10-15
WIP Standard
AS85731B
This specification covers positive locking fasteners intended for use in aircraft to secure electronic line replaceable units (LRUs).
2014-10-13
Technical Paper
2014-01-2721
Robert H. Barbour, Robert Quigley, Avtar Panesar
Abstract Diesel powered vehicles have grown in popularity over the last 15 years due to the introduction of advanced, high pressure, direct injection fuel systems that enable improved emissions, power and a more desirable driving experience. However, such vehicles only perform optimally when the fuel system is in a clean condition. When deposits form inside the injector nozzle holes, a measurable deterioration in power is observed. The CEC F-98-08 Peugeot DW10 engine test was introduced in 2008 in order to evaluate the nozzle fouling propensity of fuels and the beneficial effect of deposit control additives. Papers have been published demonstrating such effects, in particular the propensity of zinc and biodiesel contaminants to cause injector fouling and the performance of additives in both deposit control (keep clean) and removal (clean-up) modes. While running such tests with an advanced, proprietary deposit control additive, both the fuel flow (kg/hr) and engine power (kW) measured with the additised fuel were higher than the corresponding measurements made at the start of test with clean injectors running on base fuel.
2014-10-13
Technical Paper
2014-01-2700
Fredrik Königsson, Per Risberg, Hans-Erik Angstrom
Abstract Nozzle coking in diesel engines has received a lot of attention in recent years. High temperature in the nozzle tip is one of the key factors known to accelerate this process. In premixed CNG-diesel dual fuel, DDF, engines a large portion of the diesel fuel through the injector is removed compared to regular diesel operation. This can result in very high nozzle temperatures. Nozzle hole coking can therefore be expected to pose a significant challenge for DDF operation. In this paper an experimental study of nozzle coking has been performed on a DDF single cylinder engine. The objective was to investigate how the rate of injector nozzle hole coking during DDF operation compares to diesel operation. In addition to the nozzle tip temperature, the impact of other parameters on coking rate was also of interest. Start of injection, λ, diesel substitution ratio and common rail pressure were varied in two levels starting from a common baseline case, resulting in a total of 10 operating cases.
2014-10-13
Technical Paper
2014-01-2743
Luca Marchitto, Simona Merola, Cinzia Tornatore, Gerardo Valentino
Abstract Alcohols are largely used in spark-ignition (SI) engines as alternative fuels to gasoline. Particularly, the use of butanol meets growing interest due to its properties that are similar to gasoline, if compared with other alcohols. This paper aims to make a comparative analysis on the atomization process of gasoline and n-butanol fuel injected by a multi-hole injector nozzle for spark ignition engines. Phase Doppler Anemometry technique was applied to investigate the behavior of a spray emerging from a six-hole nozzle for direct injection spark ignition engine applications. Commercial gasoline and pure n-butanol were investigated. The fuels were injected at two pressures: namely at 5 and 10 MPa, in a test vessel at quiescent air conditions, ambient temperature and backpressure. Droplets diameter and velocity were estimated along the axis and on the edge direction of a jet through Phase Doppler Anemometry in order to provide useful information on the atomization process. Gasoline and n-butanol provided different results in droplets size and velocity.
2014-10-13
Technical Paper
2014-01-2850
Yingyi Wen, Shunichi Oshima
Agitation torque associated with oil lubricant is one important factor of torque loss in bearings under sufficient lubricating conditions. So far, efforts on reducing agitation torque were taken mostly by means of conventional experimental trials. Aiming for speedy, low-cost development, a calculation program for predicting the amount of agitation torque and oil distribution tendency in rolling bearings has been developed using computational fluid dynamics (CFD) analysis. At first, since rolling bearings are axially symmetric, sector models of bearings were adopted. To verify the method, torque losses and oil quantities in ordinary-sized bearings have been measured. Calculated values based on sector models are qualitatively in good agreement with measured results. The difference between the absolute values of measured and calculated torque may be caused by the difference between the vertical model used in CFD analysis and the horizontal torque-testing rig used in measurement. To improve the accuracy, full models of the bearings have been developed and verified by experiment.
2014-10-13
Standard
AMSQQA200/11A
This specification covers the specific requirements for aluminum alloy 7075 bar, rod, shapes, tube, and wire produced by extrusion. AMS-QQ-A-200/11A has been declared "STABILIZED" by AMS Committee D. This document will no longer be updated and may no longer represent standard industry practice. This document was stabilized because it contains requirements that are no longer state of the art and are also contained in alternate documents that contain equivalent requirements. Previously this document was reaffirmed. AMS Committee D has never performed a technical update of this document. Users of this document should refer to the cognizant engineering organization for disposition of any issues with reports/certifications to this specification; including exceptions listed on the certification. NOTE: In many cases, the purchaser may represent a sub tier supplier and not the cognizant engineering organization.
2014-10-13
Technical Paper
2014-01-2745
Markus Behringer, Pavlos Aleiferis, Dave OudeNijeweme, Paul Freeland
Abstract One of the latest advancements in injector technology is laser drilling of the nozzle holes. In this context, the spray formation and atomisation characteristics of gasoline, ethanol and 1-butanol were investigated for a 7-hole spark eroded (SE) injector and its ‘direct replacement’ Laser-drilled (LD) injector using optical techniques. In the first step of the optical investigation, high-speed spray imaging was performed in a quiescent injection chamber with global illumination using diffused Laser light. The images were statistically analyzed to obtain spray penetration, spray tip velocity and spray ‘cone’ angles. Furthermore, droplet sizing was undertaken using Phase Doppler Anemometry (PDA). A single spray plume was isolated for this analysis and measurements were obtained across the plume at a fixed distance from the nozzle exit. The droplet measurements were grouped into bins and maps were created showing droplet sizes and velocities against time and position during and post injection.
2014-10-09
WIP Standard
AIR5883A
This document defines the criteria used for the selection of landing gear shock strut upper and lower bearings. Common problems associated with shock strut bearings are presented.
2014-10-08
WIP Standard
J48
This SAE Recommended Practice pertains to liquid level determination for any compartment of off-road machinery as defined in SAE J1116 and J1057.
2014-10-06
WIP Standard
AS5728A
Scope Unavailable.
2014-10-06
Standard
AS24001A
No scope available.
2014-10-06
Standard
AS3485A
No scope is available.
2014-10-06
Standard
AS5972E
Scope is unavailable.
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