Military and Aerospace Applications

With the development of ES technology, the military market segment has demonstrated increasing needs for ES devices to address a variety of power challenges based on fhe unique characferisfics of ESs. They provide quick power delivery, superior low femperature operation, and the ability to handle up to a million cycles. 

In military applications, the most frequent ES use is providing backup power for elecfronics in military vehicles, fire control systems in tanks and armored vehicles, airbag deployments and black boxes on helicopters, and backup power and memory devices for handheld emergency radios. ES-based modules are also appropriate in peak power applications to facilitate reliable communication transmission on land-based vehicles, active suspension for vehicle sfabilization, GPS guided missiles and projectile systems, cold engine starts, and bus voltage hold-up during peak currents. 

Electrochemical supercapacitors (ESs) present important advantages that qualify them for many applications. In this chapter, several important ES use areas are briefly reviewed. Examples are power electronics, memory protection, battery enhancements, portable energy sources, power quality improvement, adjustable speed drives (ASDs), high power actuators, hybrid electric vehicles, renewable and off-peak energy storage, and military and aerospace applications. 

Winter, M. and R.J. Brodd. 2004. What Are Batteries, Fuel Cells, and Supercapacitors Chemical Reviews, 104,4245—4270. 

ES-based power back-up prevents data loss in RAID systems. Linear Technology Design Notes, DN487. 

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It is already over two decades since the first concepts of the use of fiber optic techniques for sensor purposes were discussed. The initial drive for the development of fiber optic sensors came from their potential use in military and aerospace applications where the cost factors of the introduction of new technology were less rigid and the working environment more hostile than is experienced with other areas of application. 

Boron is virtually unknown in the fireworks industry, but is a widely-used fuel in igniter and delay compositions for military and aerospace applications. 

Sealed cells also have many important military and aerospace applications where absence of maintenance may be important. The battery for the Viking Mars orbiting spacecraft, consisting of 26 sealed 30 Ah cells, is shown in Fig. 6.10. 

Electrolyzers are today commercially viable only in selected industrial gas applications (excepting various noncommercial military and aerospace applications). Commercial applications include the previously mentioned remote fertilizer market in which natural gas feedstock is not available. The other major commercial market for electrolysis today is the distributed, or merchant, industrial hydrogen market. This merchant market involves hydrogen delivered by truck in various containers. Large containers are referred to as tube trailers. An industrial gas company will deliver a full tube trailer to a customer and take the empty trailer back for refilling. Customers with smaller-scale requirements are served by cylinders that are delivered by truck and literally installed by hand. 

CMCs exhibit high mechanical properties at high or very high temperatures (400-3000°C), and in severe environments. They were developed initially for military and aerospace applications. Now they are being introduced into new fields and their range of applications will grow when their cost is lowered drastically. 

In conclusion, rubber-based blends are promising materials that can be designed to fulfill the requirements necessary for various types of applications— from medical devices and biomedical applications, to packaging applications, military and aerospace applications, tire industry applications, and structural applications. The chapter also addresses a new trend in the field of rubber-based product development— recycling old parts into powders and incorporating them in different matrices. 

From some of the original applications of PTFE in military and aerospace applications to new grades of FEP that provide the ultimate combination of electrical... 

Fluoroplastics have been used as wire coatings in military and aerospace applications since their discovery. They have also found their way into wire and cable applications that required extreme performance based on thermal extremes (cryogenic and high temperature applications), chemical resistance, etc., but the major market expansion in fluoroplastic use in the wire and cable industry occurred in North America when the National Electric Code (NEC) allowed polymers with low smoke-generation and flame-spread to be installed in building plenums without metal conduits. 

Military and aerospace applications often require the highest level of reliability for systems where failure can have catastrophic consequences. Fluoroplastics fill critical needs for insulation in terrestrial, aviation, and space applications. Many of these applications are defined by Military Specifications (MIL SPEC) with two of the most important being MIL-C-17 for critical coaxial cable applications and MIL-W-22759 for fluoropolymer-insulated single conductor electrical wires primarily used as aircraft wire. 

Polyimides which are available as both laminating resins and flexible films are used in military and aerospace applications where high temperature performance is critical. 

The use of nanocomposites to reinforce traditional composites has also been increasing and will continue to be a near-term trend. The emphasis for these applications, however, has been on additional mechanical reinforcement rather than flammability reduction.Since more traditional fiber-filled composites are exposed to fire risk scenarios, it makes sense to use a nanocomposite with the traditional composite to improve both mechanical and flammability performance. Of course, this does create an additional level of complexity, especially in handling the large increases in viscosity seen with nanocomposites used with thermoset composites. At this time, most nanocomposite-fiberglass/carbon fiber composites are used for military and aerospace applications, but the benefit of lightweight materials may also move these materials into automotive and mass transportation (e.g., bus, rail), where flammability performance is strongly needed. 

Al-air rechargeable batteries were designed and developed around 1992 for aerospace and other military applications. Portable Al-air rechargeable batteries were developed using both saline and alkaline electrolytes for various military and aerospace applications [3]. These batteries may not be suitable for small aircraft, small UAVs, or compact drone applications, because liquid electrolyte must be added just before use. This is the major disadvantage of these batteries. 

Phenolic resins also qualify for high-performance applications thanks to their excellent weathering and media resistance. Originally developed for military and aerospace applications, today phenolic resin composites are used for filament winding of offshore pipe for the oil and gas industry. Here, polysiloxane-modified phenolic resins are used [709]. 

Even though the demand is increasing, especially due to the military and aerospace applications, the supply is also increasing. However, as long as the production process for para-aramid remains so costly, widespread use is not likely at its current price. 

Passive Thermal Cycling. Electronic assemblies are used in a wide range of chmates. Many of these have been listed in Ref 20. However, it is advisable to measure the heating, due to the operation of the electronic devices which have considerable variation between different locations in equipment. This temperature swing, plus possible temperature excursions (e.g., going from an air-conditioned room to a hot, outdoor environment) defines the temperature swing. Additionally the temperature gradient in the application must be determined, especially in industrial, military, and aerospace applications where steep temperature ramps are possible. 

In order to meet these expectations, the central on-board computer (CDMS) was built around a microprocessor type, which has a long track record in space. The RTX2010, manufactured by Harris Semiconductor at that time, although was not a new and fast processor, but it had been especially designed for embedded control tasks in military and aerospace applications. It is a radiation-hardened stack machine processor that implements the Forth programming environment in hardware. 

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