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Offering aircraft fuel efficiency improvements of 30 to 40% over the powerplants it will replace, PW2037 retrofit in the 727-200 Advanced and B-52 aircraft is attracting heightened interest. A comparison of PW2037 technical characteristics with current aircraft powerplants substantiates the improvement potential.The engine installation and modifications necessary for aircraft system compatibility do not impose significant increases in complexity or cost. The resultant improvements in aircraft capability (727 and B-52) and economic viability to airlines (7271 produce aircraft uniquely suited to today's operational requirements and constrained equipment budgets.

The 912 engine is a well known 4-cylinder horizontally opposed 4-stroke liquid-/air-cooled aircraft engine. The 912 family has a strong track record: 40 000 engines sold / 25 000 still in operation / 5 million flight hours annually. 88% of all light aircraft OEMs use Rotax engines. The 912iS is an evolution of the Rotax 912ULS carbureted engine. The “i” stands for electronic fuel injection which has been developed according to flight standards, providing a better fuel efficiency over the current 912ULS of more than 20% and in a range of 38% to 70% compared to other competitive engines in the light sport, ultra-light aircraft and the general aviation industry. BRP engineers have incorporated several technology enhancements. The fully redundant digital Engine Control Unit (ECU) offers a computer based electronic diagnostic system which makes it easier to diagnose and service the engine.

A centrifugal pump concept was elaborated for a multiple application in future spacecrafts. Based on this concept a prototype of a small centrifugal pump was manufactured and comprehensively tested. The model pump has been approved in different test series with the fluids liquid ammonia and demineralized water. The design of the model pump was driven by the strict requirements of COLUMBUS, namely long life, noiseless operation, minimum mass and low energy consumption. Because of its modular design and as a result of selected materials of multiple compatibility, this pump is suited for the delivery of various further fluids, such as freons, hydrocarbons, propellants (hydrazine) etc.. It is also capable of pumping corrosive or toxic fluids for laboratory processes in space. The wide speed range from about 1,000 to 20,000 rpm which corresponds to a flow from about 1 to 20 l/min, permits an energy saving adaption and flow control.

This paper describes a computational technique for prediction of the flow and thermal environment in the Space Shuttle Solid Rocket Motor field joint cavities. The SRM field joint hardware has been tested with a defect in the insulation. Due to this defect, the O-ring gland cavities are pressurized during the early part of the ignition. A computer model has been developed to predict the flow and thermal environment through the simulated flaw, during the pressurization of the field joint. The transient mass, momentum, and energy conservation equations in the flow passage in conjunction with the thermodynamic equation of state are solved by a fully implicit iterative numerical procedure. Since this is a conjugate flow and heat transfer problem, wall temperatures are calculated by solving the one-dimensional transient heat conduction equation in the solid along with the other governing equations. The pressure and temperature predictions have been compared with the test data.

As the cost and complexity of modern aircraft systems increases, emphasis has been placed on model-based design as a means for reducing development cost and optimizing performance. To facilitate this, an appropriate modeling environment is required that allows developers to rapidly explore a wider design space than can cost effectively be considered through hardware construction and testing. This wide design space can then yield solutions that are far more energy efficient than previous generation designs. In addition, non-intuitive cross-coupled subsystem behavior can also be explored to ensure integrated system stability prior to hardware fabrication and testing. In recent years, optimization of control strategies between coupled subsystems has necessitated the understanding of the integrated system dynamics.

Hydrogen has difficulties in handling in a fuel cell vehicle, and has a fault with taking a big space there. The authors have proposed a hydrogen generation system using ammonia as a liquid fuel for fuel-cell electric vehicles. Ammonia has an advantage not to emit greenhouse effect gases because it does not contain a carbon atom. Hydrogen content of ammonia is 17.6 wt% and hydrogen quantity per unit mass is large. Ammonia can be easily dissociated to hydrogen and nitrogen by heating. Therefore, ammonia is an attractive hydrogen supply source for fuel cell vehicles. The ammonia hydrogen generation system of this study consists of a vaporizer, a heat exchanger and a cracking reactor with a separator. Ammonia is heated with the heat exchanger and sent to the cracking reactor, after it is evaporated through the vaporizer from the liquid ammonia. The ammonia is cracked to hydrogen and nitrogen with an appropriate catalyst.

Environmental sustainability is morphing Automotive technical development strategies and driving the evolution of vehicles with a speed and a strength hardly foreseeable a decade ago. The entire vehicle architecture is impacted, and energy efficiency becomes one of the most important parameters to reach goals, which are now not only market demands, but also based on regulatory standards with penalty consequences. Therefore, rolling drag from all bearings in multiple rotating parts of the vehicle needs to be reduced; wheel bearings are among the biggest in size regardless of the powertrain architecture (ICE, Hybrid, BEV) and have a significant impact. The design of wheel bearings is a complex balance between features influencing durability, robustness, vehicle dynamics, and, of course, energy efficiency.

In this study, the authors concluded that a super energy-efficient vehicle (SEEV) with fuel economy more than 100km/liter could be possible with the present technology level. The new environmentally-compatible vehicle was designed to mitigate urban warming, air pollution and CO2 emissions in the urban area. The authors evaluated optimal specifications of the new concept energy-efficient electric vehicle (EV) equipped with flywheel and photovoltaic (PV) cell and also reported the results of the running simulations for the proposed vehicle. The proposed SEEV will be very promising to mitigate urban and global warming, and toconserve fossil fuel consumption.

Proposed high altitude long endurance (HALE) unmanned aerial vehicle (UAV) concepts for solar powered aircraft indicate that energy storage devices will be required that significantly improve power, energy density, efficiency, and depth-of-discharge over state-of-the-art electrochemical (NiH2) batteries, without which these aircraft systems cannot become a reality. Flywheel energy storage systems offer the potential for making these systems concepts practical. However, current concepts for flywheel energy storage systems rely on energy conversion and power generation approaches that limit the available energy for aircraft use to near 60% of the fully charged capacity of the fly wheel, with efficiencies below 90%. With useable specific energy capacities below 50 Whr/kg, these systems are in capable of enabling solar-powered HALE UAV technology.

Minimizing energy use on more electric aircraft (MEA) requires examining in detail the important decision of whether and when to use engine bleed air, ram air, electric, hydraulic, or other sources of power. Further, due to the large variance in mission segments, it is unlikely that a single energy source is the most efficient over an entire mission. Thus, hybrid combinations of sources must be considered. An important system in an advanced MEA is the adaptive power and thermal management system (APTMS), which is designed to provide main engine start, auxiliary and emergency power, and vehicle thermal management including environmental cooling. Additionally, peak and regenerative power management capabilities can be achieved with appropriate control. The APTMS is intended to be adaptive, adjusting its operation in order to serve its function in the most efficient and least costly way to the aircraft as a whole.

This paper describes the continued development of a membrane-based subsystem designed to recover up to 99.5% of the water from various spacecraft waste waters. Specifically discussed are 1) the design and fabrication of an energy-efficient reverse-osmosis (RO) breadboard subsystem; 2) data showing the performance of this subsystem when operated on a synthetic wash-water solution-including the results of a 92-day test; and 3) the results of pasteurization studies, including the design and operation of an in-line pasteurizer. Also included in this paper is a discussion of the design and performance of a second RO stage. This second stage results in higher-purity product water at a minimal energy requirement and provides a substantial redundancy factor to this subsystem.

This paper describes a payload concept that is intended to better manage energy resources and enhance mission return. The payload reduces onboard data using multiple signal processing modes. Each mode is selected based on the available power resources and incoming data rate. Through software simulation, the concept is compared to the more conventional single processing mode and “unprocessed” approaches. For the chosen application, the multiple mode approach is shown to have higher performance metrics than the single mode approaches. Additionally, a significant 99.7% to a modest 4.79% net savings in energy is estimated when compared to the “unprocessed” approach.

To achieve high thermal-to-electric energy conversion efficiency, it is desirable to operate thermoelectric generator devices over large temperature gradients and also to maximize the thermoelectric performance of the materials used to build the devices. However, no single thermoelectric material is suitable for use over a very wide range of temperatures (~300-1000K). It is therefore necessary to use different materials in each temperature range where they possess optimum performance. This can be achieved in two ways: 1) multistage thermoelectric generators where each stage operates over a fixed temperature difference and is electrically insulated but thermally in contact with the other stages 2) segmented generators where the p- and n-legs are formed of different segments joined in series. The concept of integrating new thermoelectric materials developed at the Jet Propulsion Laboratory into a segmented thermoelectric unicouple has been introduced in earlier publications.

This paper is a preliminary step in the direction of the definition of a radically new wing concept that has been conceived to maximize the lift even at low speeds. It is expected to equip new aerial vehicle concepts that aim to compete against helicopters and tilt rotors. They aim achieving very good performance at very low speed (5 to 30 m/s) by mean of an innovative concept of morphing ducted-fan propelled wing that has been designed to maximize the lift force. This paper presents an effective bibliographic analysis of the problem that is a preliminary necessary step in the direction of the preliminary design of the wing. A preliminary CFD evaluation allows demonstrating that the claimed results are in line with the initial expectations. According to the CFD, results it has been produced a preliminary energetic evaluation of the vehicle in a flying car configuration by EMIPS method.

A parametric study of performance characteristics of a Loop Heat Pipe (LHP) is presented. A mathematical model, based on the steady-state energy conservation equations, is used. The calculations are performed by varying the operation conditions (heat load, sink and ambient temperatures, and elevation) and the LHP design parameters (working fluid, transport length size, external thermal conductance of the condenser and wick properties). The results are illustrated on LHP performance curves (saturation temperature as a function of applied power). All the results are compared with a baseline configuration to analyze the effects of different parameters. Operating limits due to various constraints such as heat transport limit, capillary pressure limit and the vapor pressure limit are discussed.

A newly-invented "X"-configuration engine utilizing the Scotch yoke mechanism renders potential for the best power/weight ratio of any piston engine. Due to its inherent space and weight efficiency, low stress levels on critical components and low bearing pressures, this new configuration can be designed for aircraft applications using high-pressure 4-stroke diesel cycle with large numbers of cylinders - as many as 24 or 32 cylinders - to minimize engine weight and cross-sectional area. Given the efficiency advantage of 4-stroke turbo-diesel cycle over turbine engines, a study reveals that diesel X-engines may be a preferable solution to turbine engines for airplanes, helicopters and UAVs up to approximately 60000 lbs max. weight @takeoff. Calculations using existing turbine-powered aircraft as a baseline indicate potential for 35 to 50% lower fuel consumption with no compromise to maximum takeoff weight, payload, range, cruise speed, maximum speed or takeoff power.

The Early External Thermal Control System (EETCS) is the temporary system used to collect, transport, and reject waste heat from habitable volumes on the International Space Station (ISS). The EETCS collects heat from the Interface Heat Exchangers (IFHX) located on the US Laboratory module, circulates the working fluid, anhydrous ammonia, via the Pump and Flow Control Subassembly (PFCS), and rejects heat to space via two orthogonal stationary radiators. This temporary system has been active for over three years and is nearing the end of its utilization as a means of waste heat rejection for ISS pressurized modules. This paper provides a summary of the operational history of the EETCS and presents data from several interesting nominal and off-nominal events.

A vapor-compression refrigerator/freezer with solar power and grid-backup power was tested at Johnson Space Center. The refrigerator was used to test three main energy saving devices: 1) solar power with grid-backup, 2) vacuum panel insulation, and 3) phase change material. Refrigerator power consumption and temperature were monitored while various configuration changes were made to the refrigerator. The testing of the refrigerator showed that the concepts had the potential to save energy although several drawbacks were discovered as a result of the tests.

The Energy Efficient Engine (E3) Project is directed at providing, by 1984; the advanced technologies which could be used for a new generation of fuel conservative turbofan engines. The project is conducted by NASA through contracts with the General Electric Company and Pratt & Whitney Aircraft. This paper summarizes the scope of the entire project and the current status of these efforts. Included is a description of the preliminary designs of the fully developed engines, the potential benefits of these advanced engines, and highlights of some of the component technology efforts conducted to date.

McDonnell Douglas Aerospace teamed with Pratt & Whitney and AlliedSignal Aerospace Company for the Subsystem integration Technology (SUIT) program to examine the opportunities for improvement in subsystem integration and to identify a new integration concept. This concept integrates all aircraft and engine power and cooling systems into a Thermal and Energy Management Module (T/EMM); combines gas separation and usage systems; integrates fuel pumping systems; and integrates utility subsystem controls. The T/EMM is the heart of the concept. It is powered by engine bleed air, rejects heat to engine bypass air, powers airframe and engine subsystems, and provides airframe cooling. The T/EMM can operate autonomously in emergencies or for ground operation. Performance analyses confirmed the feasibility of the T/EMM concept and demonstrated a 40% reduction in the number of components and a 1,000 lbs reduction in subsystem weight.