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The Aircraft Interiors subscription addresses the specialized needs and mechanical requirements for aircraft cabin interior design. The application of these standards will aid in the efficient and cost-effective manufacture of quality aircraft components. The standards in this resource include: Glossary of Technical and Physiological Terms Related to Aerospace Oxygen Systems Flight Deck Layout and Facilities Numeral, Letter and Symbol Dimensions for Aircraft Instrument Displays Oxygen Equipment for Aircraft Human Interface Design Methodology for Integrated Display Symbology

Abstract It is reasonable to use a two-phase heat transfer loop (TPL) in a thermal control system (TCS) of spacecraft with large heat dissipation. One of the key elements of TPL is a heat-controlled accumulator (HCA). The HCA represents a volume which is filled with vapor and liquid of a single working fluid without bellows. The pressure in a HCA is controlled by the heater. The heat and mass transfer processes in the HCA can proceed with a significant nonequilibrium. This has implications on the regulation of TPL. This article presents a mathematical model of nonequilibrium heat and mass transfer processes in an HCA for microgravity conditions. The model uses the equations of mass and energy conservation separately for the vapor and liquid phases. Interfacial heat and mass transfer is also taken into account. It proposes to use the convective component k for the level of nonequilibrium evaluation.

Abstract Improving the energy performance of batteries can increase the reliability of electric aircraft. To achieve this goal, battery management systems (BMS) are required to keep the temperature within the battery pack and cells below the safety limits and make the temperature distribution as even as possible. Batteries have a limited service life as a result of unwanted chemical reactions, physical changes that cause the loss of active materials in the structure, and internal resistance increase during the charging and discharging cycle of the battery. These changes usually affect the electrical performance of batteries. Battery life can be increased only by reducing or preventing unwanted chemical reactions. Lithium-ion (Li-ion) batteries are a suitable option due to their high specific energy and energy density advantages. In this study, the necessity of heat management is emphasized. The discharge tests of the Li-ion battery provided 94.6 Wh under 10C and 90.9 Wh under 1C.

This specification covers resin-bonded glass fibers in the form of felted pads, flat or in rolls.

This specification and its supplementary detail specifications cover rigid, cellular polyurethane or polyisocyanurate (polyether only) foam in the form of board or block.

Humidity control within confined spaces is of great importance for current NASA environmental control systems and future exploration applications. The engineered multifunction surfaces (MFS) developed by ORBITEC is a technology that produces hydrophilic and antimicrobial surface properties on a variety of substrate materials. These properties combined with capillary geometry create the basis for a passive condensing heat exchanger (CHX) for applications in reduced gravity environments, eliminating the need for mechanical separators and particulate-based coatings. The technology may also be used to produce hydrophilic and biocidal surface properties on a range of materials for a variety of applications where bacteria and biofilms proliferate, and surface wetting is beneficial.

The Mars Science Laboratory (MSL) mission to land a large rover on Mars is being prepared for Launch in 2011. A Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) on the rover provides an electrical power of 110 W for use in the rover and the science payload. Unlike the solar arrays, MMRTG provides a constant electrical power during both day and night for all seasons (year around) and latitudes. The MMRTG dissipates about 2000 W of waste heat to produce the desired electrical power. One of the challenges for MSL Rover is the thermal management of the large amount of MMRTG waste heat. During operations on the surface of Mars this heat can be harnessed to maintain the rover and the science payload within their allowable limits during nights and winters without the use of electrical survival heaters. A mechanically pumped fluid loop heat rejection and recovery system (HRS) is used to pick up some of this waste heat and supply it to the rover and payload.

The paper presents the results of a CFD study for predictions of ventilation characteristics and convective heat transfer within the Shuttle Orbiter middeck cabin in the presence of seven suited crewmember simulation and Individual Cooling Units (ICU). For two ICU arrangements considered, the thermal environmental conditions directly affecting the ICU performance have been defined for landing operation. These data would allow for validation of the ICU arrangement optimization.

The article presents convective heat transfer phenomenon by analytically and empirically taken data and CFD based model analysis. 1000 hp ASz-62IR aircraft radial engine is the object of research. This engine is being continuously operated on M18 Dromader and AN-2 aircraft. To recount heat oriented phenomena a three-dimensional CFD model was developed that accounts circumfluent flow around cylinder and cylinder head engine surfaces. The geometry includes M18 Dromader frontal airframe elements to account their influence on cooling air flow. The simulation has been conducted as a steady-state flow. Geometry and setup specific swirls and backflows were observed that increase cylinder and cylinder head rear side heat transfer coefficients. Flow along cooling fins was analysed, connecting their heat transfer coefficient dependency. Results show that local air velocity has big influence on heat flux passed by fin walls.

Aviation regulations requires that engine mounts, and other flight structures located in designated fire zones must be constructed of fireproof material so that they are capable of withstanding the effects of fire. Historically, steel is defined as being inherently fireproof, however, titanium was not. Therefore, a fireproof test was conducted using 6AL-4V titanium structure for the attachment of the propulsion system on a mid-size business jet to satisfy FAA Federal Aviation Requirement 25.865. To determine if the titanium structure would be able to support normal operating loads during the fire event, finite element analysis was performed on the titanium structure simulating the fire test. The fire test simulates a fire on the aircraft from the propulsion system by using a burner with jet fuel exposing the component to a 2000 °F (1093°C) flame. The 2000 °F (1093°C) Flame is calibrated based on FAA Advisory Circular AC20-135.

Small remotely piloted aircraft (10-25 kg) powered by internal combustion engines typically operate on motor gasoline, which has an anti-knock index (AKI) of >80. To comply with the single-battlefield-fuel initiative in DoD Directive 4140.25, interest has been increasing in converting the 1-10 kW power plants in the aforementioned size class to run on lower AKI fuels such as diesel and JP-8, which have AKIs of ~20. It has been speculated that the higher losses (short-circuiting, incomplete combustion, heat transfer) that cause these engines to have lower efficiencies than their conventional-scale counterparts may also relax the fuel-AKI requirements of the engines. To investigate that idea, the fuel-AKI requirement of a 3W-55i engine was mapped and compared to that of the engine on the manufacturer-recommended 98 octane number (ON) fuel.

In aerospace applications, it is important to have efficient, small, affordable, and reliable power conversion units with high power density to supply a wide range of loads. Use of wide-band gap devices, such as Silicon Carbide (SiC) and Gallium Nitride (GaN) devices, in power electronic converters is expected to reduce the device losses and need for extensive thermal management systems in power converters, as well as facilitate high-frequency operation, thereby reducing the passive component sizes and increasing the power density. A performance comparison of state-of-the art power devices in a 10 kW full-bridge dc-dc buck converter operating in continuous conduction mode (CCM) and at switching frequencies above 100 kHz will be presented in this manuscript. Power devices under consideration are silicon (Si) IGBT with Si antiparallel diodes, Si IGBT with SiC antiparallel diodes, Si MOSFETs, SiC MOSFETs, and enhancement-mode GaN transistors.

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.

Future aircraft systems are projected to have order of magnitude greater power and thermal demands, along with tighter constraints on the performance of the power and thermal management subsystems. This trend has led to the need for a fully integrated design process where power and thermal systems, and their interactions, are considered simultaneously. To support this new design paradigm, a general framework for codifying and checking specifications and requirements is presented. This framework is domain independent and can be used to translate requirement language into a structured definition that can be quickly queried and applied to simulation and measurement data. It is constructed by generalizing a previously developed power quality analysis framework. The application of this framework is demonstrated through the translation of thermal specifications for airborne electrical equipment, into the SPecification And Requirement Evaluation (SPARE) Tool.

Of all aircraft power and thermal loads, flight controls can be the most challenging to quantify because they are highly variable. Unlike constant or impulsive loads, actuator power demands more closely resemble random processes. Some inherent nonlinearities complicate this even further. Actuation power consumption and waste heat generation are both sensitive to input history. But control activity varies considerably with mission segment, turbulence and vehicle state. Flight control is a major power consumer at times, so quantifying power demand and waste heat is important for sizing power and thermal management system components. However, many designers sidestep the stochastic aspects of the problem initially, leading to overly conservative system sizing. The overdesign becomes apparent only after detailed flight simulations become available. These considerations are particularly relevant in trade studies comparing electric versus hydraulic actuation.

An exhaustive model of Coandã effect has not been defined, and fundamental questions are still open. One of them is the influence of convective heat exchange on Coandã adhesion. This paper presents an even preliminary numerical study of this problem. It analyses the behaviour of a fluid stream on a convex surface in the presence of a temperature gradient between the fluid and the convex surface. It approaches the problem by a set of CFD simulations, analyses previous hypotheses, which are based on Prandtl number, and evidences the need for a model that account Reynolds number. The performed simulations are still not sufficient for an exhaustive comprehension of Coandã effect in the presence of heat exchange phenomena. It allows producing some consideration that may help future scientific work in toward a better comprehension of these phenomena.

This specification covers the general requirements for the design, installation, and performance of thermal anti-icing equipment for the wings and empennage surfaces in aircraft.