Estimation of Angle of Attack in Satellite Launch Vehicle Using Flush Air Data Sensing Systems at Mach 0.5 to 3.0
R. C. Mehta
Sch J Eng Tech | 77-86
DOI : 10.36347/sjet.2021.v09i07.001
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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.
Original Research Article
Aug. 17, 2021
Design and Construction of a Portable Boiler
Akusu OM, Akinfaloye OA
Sch J Eng Tech | 87-92
DOI : 10.36347/sjet.2021.v09i07.002
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The article describes a research which is focused on the design and construction of a portable boiler. This is to enhance energy system in Africa and the world at large. Water at atmospheric pressure of 1.613252bar, 25°c was supplied to the pressure to an absolute pressure of 4.5bar, a burner and liquefied petroleum gas (LPG) were used to supply heat to the boiler that raised the water at the copper piping to a saturation temperature or 147.9°c there by producing steam. During testing 0.5kg of gas was burnt for 25min and the wet steam generated at the exist pipe was at a gauge pressure of 3.2bar. The steam generated find application in textile industries for sizing and bleaching, sugar mills, chemical industries and production of hot water for hot water supply. In conclusion, the developed modular boiler is efficient and effective at optimal working condition.
Original Research Article
Aug. 29, 2021
Assessment of Wastewater Irrigation Practices and Soil Properties in the Gazipur District of Bangladesh
Parves M, Islam MS, Biswas SK
Sch J Eng Tech | 93-101
DOI : 10.36347/sjet.2021.v09i07.003
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The study deals with the assessment of wastewater irrigation practices and soil properties in connection with demographic information, availability of water sources, health hazards and the benefit-cost analysis in the Gazipur district of Bangladesh. A questionnaire survey was carried out to collect data on farmers' perceptions and responses to mainly agricultural production issues. It found that most respondents used wastewater because they had no alternative sources and sank their land during rush hour as well as the rainy season due to the lack of a proper wastewater disposal system by adjacent industries. The majority of respondents had skin problems from working with wastewater. No significant benefits were found from using direct wastewater in the fields. Irrigation costs could be reduced, however, fertilizer costs as well as the total cost of plant production were not adequate. The farmers did not get as much grown grain as they wanted. In addition, indirect wastewater users were rated better compared to direct users from the drainage canal. Farmers' perception showed that no major impact on the consumption of crops was noted, but rather the long-term use of wastewater in the field, which gradually reduced crop production and affected soil fertility. To evaluate Ca ++, Mg ++, K +, N, P, Cu, Pb, Cd and Ni from the investigation area; It was examined that the concentration of N, P and Cd was much higher than the standard limit. The heavy metal concentration series were as follows: Cd <Cu <Ni <Pb. In summary, the overall results of the study suggest that untreated or partially treated wastewater will slowly affect land and crop production in the long run.