Browse Topic: Reusable launch vehicles and shuttles

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6.0.115 - Legal and Consumer Requirements in ASEAN CountriesSAE-PP-002702/4/2021
South East Asia is one of the regions with highest traffic-related fatality rates worldwide −18.5 fatalities per 100.000 inhabitants-. In response to that, governments of ASEAN countries are currently introducing new regulations, which will help to improve the road safety standards in the region. This paper reviews new safety regulations in force of following ASEAN countries: Singapore, Thailand, Malaysia, Indonesia, Vietnam and the Philippines. General safety trends promote the approach to international standards as well as the adoption of UNECE regulations. In fact, the 1958 agreement was signed by Thailand and Malaysia in 2006. Besides, Malaysia has gradually adopted fifty-three UNECE regulations so far and is currently considering the inclusion of twenty-four more. After the success of other NCAP organizations, the ASEAN NCAP assessment program was established in 2011. This program is powered by the Malaysian Institute of Road Safety Research (MIROS) and the Global New Car Assessment Program (GNCAP). Its purpose is to encourage manufacturers to improve the safety performance of their products by providing consumers with reliable and objective information about the protection provided by these vehicles. Vehicles launched in Cambodia, Indonesia, Lao People's Democratic Republic, Malaysia, Philippines, Singapore, Thailand and/or Vietnam can be tested, assessed and rated by this organization. The program performs a frontal impact test at 64 km/h and 40% overlap to analyze, through objective and subjective methods; the protection provided to both adult and child occupants. Scores are weighted and translated to a star rating. This paper also analyzes these assessment methods, emphasizing the innovations incorporated by this new program. Practical cases are explained to better illustrate the functioning of this new system. Safety regulations are the mainstay of road safety. Thus, the introduction of new or existing safety regulations represents a remarkable achievement but also a necessary step towards safer roads. Additionally, initiatives such as NCAP programs have also proved their effectiveness in other markets as well as its contribution to the implementation of new and safer technologies.
Mutagaana, Festo
062 - An Investigation on the Auto-Ignition of Fuel-Air Mixture Induced by Release of Oil-Fuel Droplets from Cylinder-Liner Using Multi-Zone ModelSAE-PP-002011/30/2021
This study investigated effects of gas inhomogeneity induced by droplets of fuels and oils on the auto ignition timing and temperature in the direct-injection spark ignition (DISI) engine by means of detailed numerical calculation using multi zone model. Recent researchers pointed out that droplets are made of fuels and oils which mix on the cylinder liner and released from the cylinder liner [1]. During the compression stroke released droplets reach the auto ignition temperature before flame propagation induced by spark ignition. It is called Pre-ignition. In combustion chamber, there is inhomogeneity caused by temperature and mixture distribution. In this study, the effects of gas inhomogeneity produced by droplet on the auto ignition timing and temperature have been investigated using Multi-Zone model of CHEMKIN-PRO by changing initial temperature and initial equivalence ratio. Especially, the volume of first ignition zone is focused on. As for fuels, this study used n-heptane to observe the impacts which the gas inhomogeneity has on low-temperature heat release (LTHR). As for calculation conditions, 15 zones model were assumed. Based on the assumption that the volume of the droplets from cylinder-liner is not always constant, ignition delay time and ignition temperature of mixture were confirmed, changing the volume of first ignition zone. Consequently, we found that the volume of first ignition zone affects the auto-ignition of air-fuel mixture and there is possibility to lead to cause Pre-ignition.
Mutagaana, Festo
The intent of this AIR is twofold: (1) to present descriptive summary of aircraft nosewheel steering and centering systems, and (2) to provide a discussion of problems encountered and “lessons learned” by various airplane manufacturers and users. This document covers both military aircraft (land-based and ship-based) and commercial aircraft. It is intended that the document be continually updated as new aircraft and/or new “lessons learned” become available.
A-5B Gears, Struts and Couplings Committee NEW Name Goes Her
NASA relies on the Natural Environments (NE) Branch located at Marshall Space Flight Center (MSFC) to provide databases that represent the wind magnitudes and wind changes expected on day-of-launch (DOL) for vehicle programs that MSFC NE supports. MSFC NE has traditionally utilized weather balloon measurements to generate the wind profiles used in DOL loads and trajectory simulations. However, balloon measurement archives have three limitations in that (1) they do not contain a large enough sample to adequately represent the wind environment at extreme percentiles, (2) balloons could misrepresent the aloft wind environment due to their rise rate and drift characteristics, and (3) the Space Shuttle Program’s operational requirements significantly drove the atmosphere databases’ development. To help mitigate these limitations, MSFC NE used the 50-MHz Doppler Radar Wind Profiler (DRWP) at Kennedy Space Center (KSC) to validate balloon measurements on DOL during the SSP.
A new tool calculates vehicle aerodynamic flight parameters from observed flight trajectory. These flight-observed parameters are then compared to the expected aerodynamic parameters for a nominal vehicle flying the same trajectory. The differences in the observed versus expected aerodynamic parameters are assumed to be caused by deviation in vehicle aerodynamics, the deviations caused by vehicle shape changes [damage], and/or boundary layer transition.
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