Chemical energy is the energy of chemical substances that is released when the substances undergo a chemical reaction and transform into other substances. Some examples of storage media of chemical energy include batteries, food, and gasoline. Breaking and re-making chemical bonds involves energy, which may be either absorbed by or evolved from a chemical system. If reactants with relatively weak electron-pair bonds convert to more strongly bonded products, energy is released. Therefore, relatively weakly bonded and unstable molecules store chemical energy.
The vortex tube, also known as the Ranque-Hilsch vortex tube, is a mechanical device that separates a compressed gas into hot and cold streams. The gas emerging from the hot end can reach temperatures of 200 °C (390 °F), and the gas emerging from the cold end can reach −50 °C (−60 °F). It has no moving parts and is considered an environmentally friendly technology because it can work solely on compressed air and does not use Freon. Its efficiency is low, however, counteracting its other environmental advantages.
A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, burner can, combustion chamber or flame holder. In a gas turbine engine, the combustor or combustion chamber is fed high-pressure air by the compression system. The combustor then heats this air at constant pressure as the fuel/air mix burns. As it burns the fuel/air mix heats and rapidly expands. The burned mix is exhausted from the combustor through the nozzle guide vanes to the turbine. In the case of a ramjet or scramjet engines, the exhaust is directly fed out through the nozzle.
A jet engine performs by converting fuel into thrust. How well it performs is an indication of what proportion of its fuel goes to waste. It transfers heat from burning fuel to air passing through the engine. In doing so it produces thrust work when propelling a vehicle but a lot of the fuel is wasted and only appears as heat. Propulsion engineers aim to minimize the degradation of fuel energy into unusable thermal energy. Increased emphasis on performance improvements for commercial airliners came in the 1970s from the rising cost of fuel.
Chemical looping combustion (CLC) is a technological process typically employing a dual fluidized bed system. CLC operated with an interconnected moving bed with a fluidized bed system, has also been employed as a technology process. In CLC, a metal oxide is employed as a bed material providing the oxygen for combustion in the fuel reactor. The reduced metal is then transferred to the second bed and re-oxidized before being reintroduced back to the fuel reactor completing the loop. Fig 1 shows a simplified diagram of the CLC process. Fig 2 shows an example of a dual fluidized bed circulating reactor system and a moving bed-fluidized bed circulating reactor system.
The pintle injector is a type of propellant injector for a bipropellant rocket engine. Like any other injector, its purpose is to ensure appropriate flow rate and intermixing of the propellants as they are forcibly injected under high pressure into the combustion chamber, so that an efficient and controlled combustion process can happen.
Wei ShyyJP is an aerospace engineer who served as the 4th President of the Hong Kong University of Science and Technology (HKUST) from 2018 to 2022 with his acting presidency starting from 1 February 2018. He also holds a concurrent appointment as Chair Professor of Mechanical & Aerospace Engineering. He first joined HKUST in August 2010 as Provost.
Frederick Stucky Billig was an American aerospace engineer who was a pioneer in the development of scramjet propulsion.
Theodosios Alexander is an American academic, engineer and author. He has served as faculty and in academic administration in four universities, in the UK and USA, following the award of four graduate degrees from MIT, and work in engineering industry.
Heterogeneous combustion, otherwise known as combustion in porous media, is a type of combustion in which a solid and gas phase interact to promote the complete transfer of reactants to their lower energy potential products. In this type of combustion a high surface area solid is immersed into a gaseous reacting flow, additional fluid phases may or may not be present. Chemical reactions and heat transfer occur locally on each phase and between both phases. Heterogeneous Combustion differs from catalysis as there is no focus to either phase individually but rather both examined simultaneously. In some materials, such as silicon carbide (SiC), oxide layers, SiO and SiO2, which form on the surface enable the adsorption of water vapor from the gas phase onto the solid lowering partial pressures. In this regime of combustion, thermal heat released from the combustion byproducts are transferred into the solid phase by convection; conduction and radiation both then conduct heat upstream (along with adverse convection within the gas phase). Heat is then convectively transferred to the unburnt reactants.
Elaine Surick Oran is an American physical scientist and is considered a world authority on numerical methods for large-scale simulation of physical systems. She has pioneered computational technology to solve complex reactive flow problems, unifying concepts from science, mathematics, engineering, and computer science in a new methodology. An incredibly diverse range of phenomena can be modeled and better understood using her techniques for numerical simulation of fluid flows, ranging from the tightly grouped movements of fish in Earth's oceans to the explosions of far-flung supernovae in space. Her work has contributed significantly to the advancement of the engineering profession.
A rotating detonation engine (RDE) is an engine using a form of pressure gain combustion, where one or more detonations continuously travel around an annular channel. Computational simulations and experimental results have shown that the RDE has potential in transport and other applications.
Avinash Kumar Agarwal is an Indian mechanical engineer, tribologist and a professor at the Department of Mechanical Engineering of the Indian Institute of Technology, Kanpur. He is known for his studies on internal combustion engines, Emissions, alternate fuels and CNG engines and is an elected fellow of the American Society of Mechanical Engineering (2013), Society of Automotive Engineers, US (2012), National Academy of Science, Allahabad (2018), Royal Society of Chemistry, UK (2018), International Society for Energy, Environment and Sustainability (2016), and Indian National Academy of Engineering (2015). The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards for his contributions to Engineering Sciences in 2016. Agarwal has been bestowed upon Prestigious J C Bose Fellowship of Science and Engineering Research Board. Government of India. Agarwal is among the top ten highly cited researchers (HCR) of 2018 from India, as per Clarivate Analytics, an arm of Web of Science.
Forman Arthur Williams is an American academic in the field of combustion and aerospace engineering who is Emeritus Professor of Mechanical and Aerospace Engineering at the University of California San Diego.
Peyman Givi is a Persian-American rocket scientist and engineer.
Praveen Linga PhD, a chemical engineer, is a professor at the National University of Singapore's Department of Chemical and Biomolecular Engineering. He is an expert in clathrate hydrates or gas hydrates. He is also the co-founder of NewGen Gas Pte Ltd, a spin-off company that specialises in solidified natural gas (SNG) technology via clathrate hydrates for natural gas storage and transport. He has been interviewed and has provided expert opinion and commentary in the media.
Luciano Castillo is an engineer known for his work in theoretical and experimental fluid dynamics, turbulence and wind energy and for applying scaling analysis and asymptotic methods. He is currently the Kenninger Chair Professor of Renewable Energy and Power Systems in the School of Mechanical Engineering at Purdue University, West Lafayette, Indiana, where he is also the Dean’s Faculty Fellow for Hispanic/Latino Engagement, Purdue University, (2019–present).
Hybrid rocket fuel regression refers to the process by which the fuel grain of a hybrid-propellant rocket is converted from a solid to a gas that is combusted. It encompasses the regression rate, the distance that the fuel surface recedes over a given time, as well as the burn area, the surface area that is being eroded at a given moment.
Chung King Law is a Chinese-born American scientist and a Robert H. Goddard professor at Princeton University. He is a specialist in the combustion science.
Włodzimierz Błasiak (Polish: ; is a Polish engineer and Professor at the Department of Materials Science and Engineering of the KTH Royal Institute of Technology in Stockholm. He is known for research in the areas of mineralogy, waste management, pyrolysis, energy engineering and plasma gasification. He is the winner of the 2010 George Westinghouse Medal.
