Title : Scholars Journal of Engineering and Technology Abbr. Title : Sch J Eng Tech ISSN : 2347-9523 (Print) & 2321-435X (Online) Discipline : Engineering and Technology Frequency : Monthly Publisher : Scholars Academic and Scientific Publisher Country : India Language : English
Current Issue : Volume-9 - Issue-07 Call for paper ; 2021
This paper presents an inverse analysis to estimate angle of attack during ascent period of a satellite launch vehicle. Aerodynamic results are numerically computed by solving three dimensional, time dependent, compressible inviscid equations over payload shroud of a satellite launch vehicle. The flush air data system consists of four pressure ports flushed with conical-nose section of the payload fairing and connected to on board differential pressure transducers. The inverse algorithm uses calibrations charts which based on computed and measured data. A controlled random search method is used to predict pitch, yaw and total angle of attack of vehicle from measured transient differential pressure history in flight from Mach numbers range of 0.5 to 3.0. The algorithm predicts the flow direction stepwise with function of flight Mach numbers and can be termed as online method. Flow direction of the launch vehicle is compared with the reconstructed trajectory data. The estimated values of the flow direction are found in good agreement them.
Coarse aggregates derived from rock are commonly used as road pavement materials that meet the applicable specifications. This study uses rock aggregates originating from the polymeric area of Jayapura City, and this type is widely found in various areas of northern Papua. The study was conducted to determine the effect of local Papuan coral aggregates on the AC-WC Laston value. According to the 2018 General Specifications of Highways; namely, the added filler material must be dry and free from clumps and when tested by sieving according to SNI ASTM C136: 2012. The test results obtained characteristic values on the use of coral as follows: The highest density value at 4.5% asphalt content and the lowest 5.5% and 6.5%. The VMA value obtained is unstable, but all asphalt content meets Bina Marga Specifications 2010 Revision III, namely with a minimum VMA value of 15%, the highest VIM value of 3-5%, VFA values tend to increase but experience a decrease in asphalt content of 5.5% and 6.5%. The results of the Marshall test on coral material in the AC-WC layer are the high strength value 5495.89 kg, density: 1.74 gr/cm3, VMA: 24.42%, VIM: 15.83 %, VFA: 0.01%, flow: 10.00 mm, and MQ of 348.03 mm/kg. The value of Optimum Asphalt Content (KAO) used as AC-WC layer is 5.5%.
With the increasing diameter and stress the power applied to motor wheel may increase in proportional, which means the big power will be formed in forge process of motor. Furthermore with increasing height and rotation it may increase as well. So that through power equation to be established the properties may be designed and checked before made. Detail value is needed to calculate the hub power according to the curves between them. The stress of hub is the first factor to consider and then its diameter and height which is second factor. The bigger power is 12KW and 35KW when rotation is 10r/m and height is from 350mm to 150mm respectively. That means that in the scope of this field the power may be bigger enough. When continuing to incline height the power will no change. The time increases as diameter and height inclines. The time will incline as the rotation declines.