Environmental impact assessment of a newly developed solid oxide fuel cell-based system combined with propulsion engine using various fuel blends for cleaner operations

After the COVID-19 pandemic has spread throughout the world, many research institutions and industrial organizations are putting great efforts into producing environmentally friendly solutions for the transportation sector. This paper presents a newly developed combined solid oxide fuel cell with a turbofan engine that can use five alternative fuels, such as dimethyl ether, methanol, hydrogen, methane, and ethanol, with different blending ratios to form five fuel blends. The proposed system is studied in this paper using exergoenvironmental analysis (which is known as environmental impact assessment by exergy) in order to quantify and evaluate the environmental impact. The combined turbofan has an exergetic efficiency of 82%, with total fuel and product exergy rates of 905 and 743 MW, respectively. The total environmental impact due to emissions and exergy destruction has a range of 4000 to 9000 Pt/h for all the fuel blends. The specific exergoenvironmental impact values of electricity production vary from about 3 to 8 mPt/MJ for solid oxide fuel cells and 10 to 25 mPt/MJ for three turbines. The exergoenvironmental impact of thrust force is a minimum of 34 Pt/(h.kN) for RF1 and a maximum of 87 Pt/(h.kN) for RF4.

Second-Year Review of the NSF-DoD REU Site: HYPER

The challenges associated with achieving hypersonic flight, developing advanced propulsion systems, and designing reusable launch platforms are strongly interdisciplinary. Exposing undergraduate students to interdisciplinary research is recognized as a means to equip society's future engineers and scientists with the broad skillset necessary to contribute to these areas. The jointly funded NSF-DoD REU site Advanced Technologies for Hypersonic Propulsive, Energetic and Reusable Platforms (HYPER) unites multidisciplinary interests to study advanced structures and systems with application to hypersonics, space, propulsion, and energy. Over the course of two 10-week summer sessions (2019 and 2021), participants have gained hands-on training in contemporary challenges such as: (1) utilizing advanced manufacturing techniques for high-value components, (2) integrating in situ monitoring of stress-strain evolution, (3) developing novel methods for improved internal cooling and heat transfer effectiveness, (4) mitigating flutter through advanced rotor dynamic control, etc. Eleven research projects have been crafted to engage students in PhD-level topics. Many of these challenges rely on approaches that cut across disciplines and research techniques (e.g., experiments and computer simulation). The present reporting serves as a synopsis of challenges, advances, and lessons learned conducting the research thus far. The site HYPER has six core objectives that relate to: (1) preparing students for graduate school and/or research-oriented careers, (2) fostering technical skills in student participants, (3) improving participants' communication skills, (4) marketing to and recruiting a diverse group of participants, and more. Assessment of the program outcomes according to these objectives are reported here with data gathered after two years. Program outcomes were conducted with an external evaluator affiliated within the University of Central Florida's Program Evaluation and Educational Research Group (PEER). Results demonstrate a very effective site with strongly positive outcomes for all participants. Insights are provided so this research effort may be confirmed by other independent sites. It should be noted that the 2020 session was postponed out of an abundance of caution based on the uncertain and evolving conditions facilitated by the COVID-19 pandemic. © American Society for Engineering Education, 2022.

Passive Method for Wax Casting in the Production of the Fuel Grain for in-space Hybrid Rocket

The Space Enabled Research Group at MIT is conducting a multiyear research effort to better understand the technical and logistical challenges posed by the implementation of a wax-based hybrid chemical in-space propulsion system. Paraffin and beeswax are being considered as candidate fuels. The overarching effort includes imagery analysis conducted on paraffin and beeswax centrifugal casting tests conducted onboard progressively higher-fidelity experimental platforms within transparent hardware which aids in optical investigations. Such platforms include a laboratory optical table experiment, as well as a vacuum chamber test, a parabolic trajectory microgravity aircraft (three flights to date), the Blue Origin New Shepard suborbital launch vehicle (three experiments onboard and scheduled for mid to late 2022), and potentially the Destiny laboratory module of the International Space Station. Each of these platforms allows for testing in a new environment or increasingly longer-duration microgravity. The main focus of this paper is in regards to a Suborbital flight experiment. This experimental setup had multiple limiting factors such a size, 10 cm x 10 cm x 20 cm and power of approximately 5 W. This lead to trying a new approach to the spin casting approach used previously by the team, as the method of forming the fuel grain annulus. This new approach was passive, meaning it did not require any additional power other than to melt the wax, and relied heavily on the surface tension properties of the containment chamber. The surface tension of the end caps was modified by using an oleophobic substance to repel the wax. Unfortunately, due to the Covid-19 pandemic, delays on flight caused results to not be ready before the date of publication of this paper. © 2022, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

System Approach to Electric Machines Development for Aviation Hybrid Propulsion Systems Under Economic Crisis

In this article, the process of electric machine development for aircraft with hybrid propulsion system is considered at all development stages: From the formation of technical task to the bench tests. Electric generator power of 400 kW and rotational speed of 12 000 r/min intended for aircraft with hybrid propulsion system passenger capacity of 9-19 seats was used as an example. The most problematic places and possible solutions are identified. The problems that can be revealed from each design part are considered and its influence on the entire development process is analyzed. We analyzed the influence of technological parameters in the prototyping on the accuracy of computer simulation. We also described the accident that occurred during the testing of the experimental sample, analyzed the causes of its occurrence and identified the consequences.