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©Мирзокобилова Ф., Нозиров Д., Салиев М.А.,Абдуллаев С.Ф.,Кабутов К., 2020
УДК 62-6
Сергеева Г. В.
Старший преподаватель, Самарский университет, г. Самара
Стрельникова Д. В.
Студент, Самарский университет, г. Самара
ADVANTAGES AND DISADVANTAGES OF BIOFUELS IN AVIATION
Annotation
This article touches on important points regarding the advantages and disadvantages of jet biofuels, provides statistics on fuel consumption by airlines, describes the reasons why it is necessary to switch to biofuels and develop new, more advanced types.
Keywords:
biofuels, aviation industry, ecology, the benefits and harms of new fuels.
Every day in the world more than 100 thousand flights are operated. World aviation consumes about 300 million tons of fuel per year. These numbers perfectly reflect the scale and complexity of the aviation fuel supply system. The depletion of hydrocarbon reserves, rising energy prices, the growing dependence of the economy on the oil sector make it necessary to search for new non-traditional sources of energy.
According to the Air Transport Association, fuel consumption is a serious environmental and financial problem. The Federal Aviation Administration (FAA) estimates that by 2030, the U.S. fleet of commercial aircraft will consume more than 110 billion liters of fuel, compared to 68 billion liters this year, and about 160 million people will fly on US aircraft compared to the current 70. 7 million, according to the agency. These numbers are shocking, right?
Every year, the aviation industry is under increasing pressure from the public and environmentalists, who claim that increasing traffic and the number of aircraft in operation causes serious damage to the environment, and aviation is one of the largest consumers of fuels and lubricants. Therefore, back in 2008, the leading representatives of the aviation industry came to a common opinion on the need to increase the fuel efficiency of operating aircraft by 1.5% by 2020. From the beginning of 2020, a limitation on harmful emissions in aviation will be introduced, and by 2050 it is planned to reduce carbon dioxide emissions by up to 50% compared with the figures for 2018.
On other modes of transport there is a wide selection of alternative energy sources, the most popular is
electricity, but in this regard the aviation industry remains on the sidelines, since the use of electricity involves the use of heavy batteries, in addition, they lack the power needed to take off the aircraft. Thus, almost the only alternative energy source in aviation remains biofuels derived from renewable natural resources. It is the use of biofuels that can achieve the goal of reducing CO2 emissions in the near future.
Biofuels last longer than cars, but cheap gasoline and diesel kept them on the edge for a long time. The spike in oil prices, as well as global efforts to prevent the worst effects of climate change, are pushing professionals to look for more clean, renewable fuels. The idea of biofuels is to replace traditional fuels with those made from plant materials or other types of raw materials that are renewable. But the concept of using agricultural land to produce fuel instead of food has its own problems, and solutions based on waste or other raw materials have not yet been able to compete in price and scale with traditional fuels. Global biofuel production should triple by 2030 to meet the International Energy Agency's goals for sustainable growth.
There are various methods for producing biofuels, but they usually use chemical reactions, fermentation, and heating to break down starches, sugars, and other molecules in plants. The resulting products are then refined to produce fuel that cars or other vehicles can use. Most gasoline in the United States contains one of the most common biofuels: ethanol. Made by fermenting sugar from plants such as corn or sugarcane, ethanol contains oxygen, which helps the car's engine burn fuel more efficiently, reducing air pollution. In the United States, where most ethanol is derived from corn, fuel typically consists of 90 percent gasoline and 10 percent ethanol. In Brazil, the second largest ethanol producer after the United States, fuel contains up to 27 percent ethanol, with sugarcane being the main raw material. [1]
Biofuels derived from oil-rich raw materials such as camellina and algae have been successfully tested to prove conceptual flights. ASTM International, an international standards development organization, has approved a 50:50 mixture of petroleum-based jet fuels and hydrofinished renewable jet fuels for commercial and military operations. However, even after considerable research and commercialization efforts, current biofuel production volumes are very small. The production of these products on a larger scale will require further technological improvements and plentiful inexpensive raw materials (crops used for fuel production). Sugarcane is a well-known source of biofuel: Brazil has fermented sugarcane juice for decades to produce alcohol-based fuels. Sugarcane ethanol provides 25 percent more energy than the amount used in the manufacturing process and reduces greenhouse gas emissions by 12 percent compared to fossil fuels. We wondered if we could increase the production of natural oil at the plant and use oil for biodiesel production, which provides even greater environmental benefits. Biodiesel provides 93 percent more energy than is required for its production, and reduces emissions by 41 percent compared to fossil fuels. Ethanol and biodiesel can be used in biofuel fuel, but technologies for converting vegetable oil to jet fuel are at an advanced stage of development, provide high energy efficiency and are ready for large-scale implementation. So is biofuel relevant now and what are its disadvantages?
Advantages of Biofuels
1. Cost Benefit: As of now, biofuels cost the same in the market as gasoline does. However, the overall cost benefit of using them is much higher. They are cleaner fuels, which means they produce fewer emissions on burning. Biofuels are adaptable to current engine designs and perform very well in . So, the use of biofuels will be less of a drain on the wallet.
2. Easy to Source: Whereas oil is a limited resource that comes from specific materials, bio-jet fuel can be produced from various plant materials, including oil crops, sugar crops, starchy plants and lignocellulosic biomass, through various chemical and biological routes.
3. Reduce Greenhouse Gases: Fossil fuels, when burnt, produce large amount of greenhouse, these greenhouse gases trap sunlight and cause planet to warm. To reduce the impact of greenhouse gases. Studies suggests that biofuels reduces greenhouse gases up to 65 percent.
4. Economic stimulation: Because biofuels are produced locally, biofuel manufacturing plants can employ hundreds or thousands of workers, creating new jobs in rural areas. Biofuel production will also increase the demand for suitable biofuel crops, providing economic stimulation to the agriculture industry.
Disadvantages of Biofuels:
1. Future Rise in Price: now, the prices are comparable with gasoline and are still feasible. Constantly rising
prices may make the use of biofuels as harsh on the economy as the rising gas prices are doing right now.
2. Shortage of Food: Biofuels are extracted from plants and crops that have high levels of sugar in them and which are used as food. Even if it does not cause an acute shortage of food, it will definitely put pressure on the current growth of crops. One major worry being faced by people is that the growing use of biofuels may just mean a rise in food prices as well.
3. Water Use: Large quantities of water are required to irrigate the biofuel crops and it may impose strain on local and regional water resources, if not managed wisely. In order to produce corn based ethanol to meet local demand for biofuels, massive quantities of water are used that could put unsustainable pressure on local water resources.
4. Use of Fertilizers: Biofuels are produced from crops and these crops need fertilizers to grow better. The downside of using fertilizers is that they can have harmful effects on surrounding environment and may cause water pollution. Fertilizers contain nitrogen and phosphorus. They can be washed away from soil to nearby lake, river or pond. [2]
Thus biofuels produce less greenhouse gas emissions than fossil fuels, but this can only slow down global warming, and can not stop or reverse it. Biofuels can only be replaced for a short time, as we invest in other technologies. The key to their implementation is mitigation of the environmental impact.
In accordance with my analysis, it should be assumed that biofuels have their drawbacks, but in my opinion there are more advantages, and the most important thing is to continue moving in this direction, creating new more environmentally friendly fuels, because caring for the environment is caring for the future.
References:
1.Aviation Industry Looks to Solve a Carbon Problem. AUTHOR: Scott Detrow. https: //www .scientificamerican.com.
2.Are Advanced Biofuels for Airplanes Ready for Takeoff? AUTHOR: John Fialka. https: //www .scientificamerican.com.
© Сергеева Г.В., Стрельникова Д.В., 2020
УДК62
Р.Р. Харисов
сотрудник Академии ФСО России,
г. Орел, РФ E-mail: rinal97@yandex.ru
ОЦЕНКА ВЫИГРЫША ОТ КОДИРОВАНИЯ И АЛГОРИТМИЧЕСКОЙ СЛОЖНОСТИ ПОМЕХОУСТОЙЧИВЫХ КОДОВ ДЛЯ ЗЕМНОГО КВ-РАДИОКАНАЛА
Препятствиями на пути активного применения средств специальной декаметровой радиосвязи до недавнего времени были их громоздкость, сложность в эксплуатации, низкие пропускная способность и надежность связи. Развитие схемотехники и микроэлектроники стимулировало успехи в развитии технологии передачи, особенно в части построения модемного оборудования декаметровой радиосвязи.
Стремительно развивающиеся технологии цифровой обработки и передачи пакетных данных в канале декаметровой радиосвязи позволяют в общем случае реализовать современные методы повышения помехоустойчивости и помехозащищенности, однако ценой низкой энергетической эффективности передачи радиосигналов. В работе выдвигается гипотеза о возможности повышения энергетической эффективности в канале декаметровой радиосвязи при предоставлении услуг телефонии за счёт согласования статистических свойств канала КВ-радиосвязи и параметров помехозащищенных радиосигналов, канальных кодов и адаптации их к сигнально-помеховой обстановке.
