Public awareness regarding pollutants and their adverse health effects has created an urgent need for engineers to better understand the combustion process as well as the pollutants formed as by-products of that process. To effectively contribute to emission control strategies and design and develop emission control systems and components, a good understanding of the physical and mathematical principles of the combustion process is necessary. This seminar will bring issues related to combustion and emissions "down to earth," relying less on mathematical terms and more on physical explanations and analogies.
Aero-engine oil systems need to pump and de-aerate air-oil in a two-phase flow. The oil lubrication systems combine three important functions of the Main Oil Pump (MOP) for lubrication and scavenging: the de-aeration and de-oiling of the air-oil mixture generated in the bearing and gearbox sumps, and pumping the oil towards the tank. These are critical functions for the engine. An engine lubrication system and an integrated pump and separation of gas-liquid mixture has been developed and characterized experimentally to increase UTAS Engine and Control Systems research and development productivity, as well as engine reliability and system performance. This pump and separator system is specially designed to handle air-oil mixtures generated in aero-engine lubrication systems. To address this need, a Computational Fluid Dynamic (CFD) analysis of the pump and separation system that allows in-flight performance prediction is presented in this paper.
A major challenge to sustainable development is the minimization of environmental impact of energy resource utilization and enhancement of resource utilization efficiency. The limitations on sustainable development of air transport systems due to environmental emissions can be to certain extent overcome through enhanced efficiency by reducing emissions and environmental damage cost. Exergy, and exergo-environmental analysis of air-craft systems are currently the subject of research. Energy, which is defined as the thermodynamic departure of a substance from the surrounding can be considered and accepted as a suitable measure to evaluate environmental impact of energy use. The present article carries out energy, exergy and exergo-environmental analysis of a CT7-7A turboprop engine manufactured by GE Aviation. Film cooling is used as the method of turbine bucket cooling.
The Italian Aerospace Research Center is currently developing the design of a HAPS (High Altitude Pseudo Satellite). Different HAPS configurations have been proposed in recent years. Airbus Zephyr family and Aurora Odysseus are based on the flying wing configuration. Thales Stratobus is an airship, while Google Loon project is based on balloons. Our proposal concerns a hybrid configuration where the weight is balanced by both aerodynamic and aerostatic forces. In this paper we present the tools we have implemented to develop the conceptual design of our platform. The tools have been implemented in Mathworks Matlab® and Grasshopper® integrated with Rhino 3-D. In the Matlab environment, we have developed an optimization algorithm which can estimate some geometric and energetic global parameters of the platform (weight, surface, volume, required power, width, length and height) using as input the desired speed, altitude and period of the year in which the mission will be performed.
Hybrid-electric gas turbine generators are considered a promising technology for more efficient and sustainable air transportation. The Ohio State University is leading the NASA University Leadership Initiative (ULI) Electric Propulsion: Challenges and Opportunities, focused on the design and demonstration of advanced components and systems to enable high-efficiency hybrid turboelectric powertrains in regional aircraft to be deployed in 2030. Within this large effort, the team is optimizing the design of the battery energy storage system (ESS) and, concurrently, developing a supervisory energy management strategy for the hybrid system to reduce fuel burn while mitigating the impact on the ESS life. In this paper, an energy-based model was developed to predict the performance of a battery-hybrid turboelectric distributed-propulsion (BHTeDP) regional jet.
This paper presents design considerations in utilizing cable impedance calculations in the design of an aerospace electrical power system. (EPS) Past wiring design guidelines featured a tabular constructed single-point design reference. This results in a cable selection which adds unnecessary weight and under-utilized the wire’s performance ability when considering a vehicle’s design requirements. Present wiring design guidelines have lagged behind the growing movement to achieve an optimized wire selection. Understanding the shortfalls with past and present wiring design methods will improve future methods to comply with increasingly restrictive vehicle performance requirements. This paper will discuss two of the most important design requirements for future aerospace electrical power and distribution feeders, which are weight and thermal limits assigned to an EPS design.
Through the substitution of some aircraft structural components with power storage and generation devices that possess adequate structural strength and stiffness, flight endurance time and performance of solar powered unmanned aerial vehicles (UAV’s) may be increased by reducing the parasitic weight penalties of the power systems. This innovation of the ‘Flying Battery’ along with energy generation devices such as structural solar cells, thermo-electric generators, and vibration induced power generators are integral to creating a flying structure that will be more efficient and more useful to the electric powered commercial and hobby markets. This paper discusses plans and the progress toward achieving potential endurance and efficiency increases in unmanned aerial vehicles through laboratory and eventual model flight experiments of novel structural designs for graphene super-capacitors, solar cells, and other power generation devices.
Industrial robots have been around since the 1960s and their introduction into the manufacturing industry has helped in automating otherwise repetitive and unsafe tasks, while also increasing the performance and productivity for the companies that adopted the technology. As the majority of industrial robotic arms are deployed in repetitive tasks, the pose accuracy is much less of a key driver for the majority of consumers (e.g. the automotive industry) than speed, payload, energy efficiency and unit cost. Consequently, manufacturers of industrial robots often quote repeatability as an indication of performance whilst the pose accuracy remains comparatively poor. Due to their lack in accuracy, robotic arms have seen slower adoption in the aerospace industry where high accuracy is of utmost importance. However if their accuracy could be improved, robots offer significant advantages, being comparatively inexpensive and more flexible than bespoke automation.
In this paper, a MATLAB-Simulink based general co-simulation approach is presented which supports multi-resolution simulation of distributed models in an integrated architecture. This approach was applied to simulating aircraft thermal performance in our Vehicle Systems Model Integration (VSMI) framework. A representative advanced aircraft thermal management system consisting of an engine, engine fuel thermal management system, aircraft fuel thermal management system and a power and thermal management system was used to evaluate the advantages and tradeoffs in using a co-simulation approach to system integration modeling. For a system constituting of multiple interacting sub-systems, an integrated model architecture can rapidly, and cost effectively address technology insertions and system evaluations. Utilizing standalone sub-system models with table-based boundary conditions often fails to effectively capture dynamic subsystem interactions that occurs in an integrated system.
Aerospace application Line Replaceable Unit (LRU) development is tedious process involving hardware development and software development. Detail testing to be performed as per design assurance level (DAL) level of the system in which the LRU used. LRU design and developed for control application of a system to be tested on the real plant/system. Early system requirements validation during development stage using real plant / system involves high risk causing damage to system impacts high lead time to fix the system or most of time system itself is not built yet or system not available at the location of LRU design and development for system functional testing. However real-time simulation environment can address these limitations of system testing. Real time simulation environment is one platform extensively used for control system validation during initial stage of LRU design and development by simulating plant model / system.
Faced with increasingly stringent emission requirements, PEMFC (Proton Exchange Membrane Fuel Cell) is regarded as the next-generation power source, which has the advantages of zero-emission, high efficiency and high specific energy. The design of the flow channel structure is the most important part of fuel cell design. In this paper, on the premise of cost control, the velocity and pressure distribution in the straight flow channel with different cross-section shapes (rounded rectangle, trapezoid, arc), the cathode and anode flow channels, the current density distribution in the catalytic layer, and the water distribution in the proton exchange membrane were discussed. The influence of flow channel structure on single flow channel, single fuel cell and fuel cell stack were deeply discussed, and one or several excellent flow channel design schemes were obtained by comparing the output power and efficiency of fuel cells.
Most composite assemblies and structures generally fail due to the poor performance of their bonded joints that are assembled together with an adhesive layer. Adhesive failure and cohesive failure are among the most commonly observed failure modes in composite bonded joint assemblies. These failure modes occur due to the lack of reinforcement within the adhesive layer in transverse direction. The overall performance of any composite assembly largely depends on the performance of its bonded joints. Various techniques and processes were developed in recent years to improve mechanical performance of the composite bonded joints, one of which includes the use of nanoscale reinforcements within the adhesive layer in between the adherends. However, most prior research have been focused on use of straight carbon nanotubes (CNTs) and other nanomaterials in particle forms. The goal was to improve the properties of the adhesive film and their interfacial bonding effectiveness.
This specification covers a petroleum-based reference oil. This fluid has been typically used as a reference oil to evaluate the ability of elastomeric compounds to conform to specified requirements after immersion at a specified time and temperature as required by the material.