Engineering Headway Vol. 5

Abstract: A new form of composite PCMs is developed by adding 0.5 wt% of SiO₂, TiO₂, ZnO and CuO nanomaterials to lauric acid. Phase change temperatures of lauric acid range from 43.92°C to 44.65°C and 40.84°C to 41.36°C, respectively. In addition, the phase change latent heats are 183.23 kJ/kg and 183.68 kJ/kg at room temperature, respectively. Thermal properties of PCM with nanomaterials were discussed in terms of weight fractions. The improvement in thermal conductivity of the PCM owing to the dispersion of nanomaterials was verified by laser flash analyser (LFA). Hence, the newly developed composite PCMs holds great potential as a candidate for harnessing solar energy in low-temperature heating systems. Keywords: Phase Change Material (PCM), Melting, freezing, Nanomaterials and Lauric acid.

Abstract: The importance of fossil fuel in our day-to-day life cannot be described in words. Worldwide fossil fuel usage amounted to around 128,550 terawatts per hour. Keeping all the necessity of fossil fuel in our daily life, we cannot deny the fact that the vast usage of fossil fuel is one of the most vital reasons behind global warming and climate change. Many reports claim that the global temperature has increased by 1°C dues to excessive usage of fossil fuels. Moreover, the resources of fossil fuel are limited and humanity may run out of these limited resources in the future. In order to reduce global warming, in this study, we are proposing to increase the usage of solar energy instead of fossil fuel using mathematical modeling techniques. We have formulated a three-compartmental model with the compartments Global Temperature, Fossil Fuel Consumption and Solar Energy Consumption with interactions between the compartments. We have conducted both qualitative and numerical analysis of the model. The qualitative analysis includes the study of equilibrium, stability, nature of the stability at the equilibrium points. From the results of the numerical analysis, we can conclude that increasing the usage of solar systems can effectively reduce global warming. In countries like Bangladesh, the vast implementation of solar energy can be more effective than in other countries as the average temperature remains quite higher than in other countries, also for the availability of enough sunlight.

Abstract: Fossil fuel usage for power generation has been associated to several harmful environmental impacts, such as the release of greenhouse gases and the production of acid rain. As a more sustainable option, utilizing renewable energy sources, such as hydro and wind power, has gained popularity in recent years. In 2020, approximately 4500 TWh and 1600 TWh of global electricity were generated from hydropower and wind power worldwide respectively. This proves, both wind and hydroelectric power have a great deal of potential for producing electricity sustainably. Moreover, using these renewable energies can significantly reduce acid rain. SO₂ (Sulphur Dioxide) and NO (Nitrogen oxide) emissions from burning fossil fuels combine with atmospheric water vapor generates H₂SO₄ (sulfuric acid) and HNO₃ (nitric acid), what causes acid rain. Acid rain can be reduced by using hydroelectric and wind energy instead of fossil fuels. This study points out the benefits of using hydro and wind power for eco-friendly electricity production and minimizing acid rain. A five-compartmental mathematical model included hydropower (H), wind power (W), fossil fuel (F), acid rain (A) and electricity (E) has been investigated here. The qualitative analysis of the model refers that, using hydro and wind power makes sustainable production of electricity easier and reduces acid rain.

Abstract: Air quality monitoring of any specific location is important for continuous improvement of air quality and protecting public health. We demonstrate the design and development of an autonomous copter-type air quality monitoring drone to measure the amount of CO₂ and CO present in the ambient air of any desired trajectory. We also measured the temperature, pressure, and humidity of the surrounding air. The proposed low cost drone is small in size, light weight, easy to maintain, and capable of flying a long distance. In addition to autonomous control, the proposed drone can be manually controlled using a long-range remote controller. The maximum altitude of the drone from the ground control station is approximately 500 m, whereas the maximum velocity is 50 km/hour. During air quality monitoring, we collected the air quality data from 1 feet to 200 feet with 20 feet interval where the average velocity of the drone was 5.4 km/hour. We selected three different locations for data collection. Afterwards, we analyzed the collected data and determined the primary causes of variation in the CO₂ and CO concentration of various locations under different altitudes. We strongly believe that, the proposed drone will be useful for collecting location specific air quality information and taking necessary actions to reduce air pollution.

Abstract: This paper demonstrates the design and fabrication of an autonomous multi-functional hexacopter drone. The proposed drone can spray liquid pesticides at a rate of 1 liter/minute using a high-speed automatic pesticides sprayer integrated with the drone. For surveillance application, a high-definition camera and a video transmitter have been included with the drone that can capture and transmit real-time video of any desired trajectory. We also utilized the captured images for ortho-photography. The hexacopter drone can fly at a maximum velocity of 36 kilometer/hour with a maximum altitude of 200 meters. The maximum range of the drone is approximately 2 kilometers, whereas the maximum endurance of the drone is ~ 25 minutes when flying at an altitude of 10 meters. The empty weight and payload capacity of the drone are 5.0 kg and 4.4 kg. The flying path of the drone is autonomously controlled from the ground control station. In addition, the drone can be manually controlled by means of a remote controller. The production cost of the drone is just within 1,600 $. The developed autonomous multi-functional hexacopter drone is suitable for wide range of commercial applications including agricultural, surveillance & monitoring, and aerial shooting.

Abstract: This research illustrates a simple mono-rectangular cored symmetrical PCF (MRC-SPCF) sensor that is used for detecting different concentrated glucose samples (from 0% to 60%). The simulations are carried out within 1-2 THz regimes based on the principles of the finite element method (FEM). After a completed investigation we have found the values of a range of optical properties that are comparable to the previously published results. From our investigation, we found 94.43% relative sensitivity with a negligible effective material loss (EML) of 0.004 cm^-1 at 1.8 THz respectively for 60% and 20% concentrated glucose solution. Besides this proposed MRC-SPCF sensor also expresses almost zero confinement losses for all the glucose samples within the operated frequency range. Hence we can admire that this proposed MRC-SPCF sensor can be a potential aspirant in chemical sensing which can make an impact both in the medical and industrial sectors.