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Guide describes step-by-step process for installation of interior surface-mounted FCC used in commerical and residential buildings. Photographs illustrate how cable-riser and baseboard covers are installed as well as receptacle assembly and receptacle-cover replacement.
The National Renewable Energy Laboratory's Electrical Infrastructure Cost Model is an Excel-based tool designed to estimate the electrical infrastructure costs of marine energy components and subsystems. It incorporates data collected from offshore wind projects, utility projects, and other relevant sources to provide accurate and comprehensive cost projections. With its user-friendly interface, the model allows users to input various parameters related to the system array, electrical cables, and substations. By leveraging industry data, cost trends, and technological advancements, the model generates outputs that include system array sizing, electrical cable specifications and costs, substation specifications and costs, and total electrical infrastructure costs. One of the notable strengths of the model is its flexibility in covering multiple-orders-of-magnitude scaled systems, accommodating projects ranging from proof-of-concept or pilot-scale installations to large-scale offshore systems. By collecting data largely from offshore wind reports and utility projects, the model incorporates real-world conditions and accounts for industry-specific factors. It incorporates cost trends and sizing relationships to deliver cost estimations for electrical infrastructure components, such as electrical cables and substation equipment.
Steel cable was chosen for the lower end of the drogue and main parachute risers on NASA's Orion Multi Purpose Crew Vehicle Parachute Assembly System (CPAS) to protect the risers from extreme temperatures and abrasion should they contact the crew module during deployment, as was done for Apollo. Due to the weight and deployment complexity inherent in steel, there was significant interest in the possibility of substituting textile for steel for the drogue and main parachute risers. However, textile risers could be damaged when subjected to high temperature and abrasion. Investigations were consequently performed by a subset of the authors to determine whether sacrificial, non-load-bearing textile riser covers could be developed to mitigate the thermal and abrasion concerns. Multiple material combinations were tested, resulting in a cover design capable of protecting the riser against severe riser/crew module contact interactions. A feasibility study was then conducted to evaluate the performance of the textile drogue riser cover in relevant abrasive environments. This paper describes the testing performed and documents the results of this feasibility study.
This paper presents the tests and analytical approach used on the development of a steel riser cutter for the CEV Parachute Assembly System (CPAS) used on the Orion crew module. Figure 1 shows the riser cutter and the steel riser bundle which consists of six individual cables. Due to the highly compressed schedule, initial unavailability of the riser material and the Orion Forward Bay mechanical constraints, JSC primarily relied on a combination of internal ballistics analysis and LS-DYNA simulation for this project. Various one dimensional internal ballistics codes that use standard equation of state and conservation of energy have commonly used in the development of CAD devices for initial first order estimates and as an enhancement to the test program. While these codes are very accurate for propellant performance prediction, they usually lack a fully defined kinematic model for dynamic predictions. A simple piston device can easily and accurately be modeled using an equation of motion. However, the accuracy of analytical models is greatly reduced on more complicated devices with complex external loads, nonlinear trajectories or unique unlocking features. A 3D finite element model of CAD device with all critical features included can vastly improve the analytical ballistic predictions when it is used as a supplement to the ballistic code. During this project, LS-DYNA structural 3D model was used to predict the riser resisting load that was needed for the ballistic code. A Lagrangian model with eroding elements shown in Figure 2 was used for the blade, steel riser and the anvil. The riser material failure strain was fine tuned by matching the dent depth on the anvil with the actual test data. LS-DYNA model was also utilized to optimize the blade tip design for the most efficient cut. In parallel, the propellant type and the amount were determined by using CADPROG internal ballistics code. Initial test results showed a good match with LS-DYNA and CADPROG simulations. Final paper will present a detailed roadmap from initial ballistic modeling and LS-DYNA simulation to the performance testing. Blade shape optimization study will also be presented.
Wire cable absorbs energy at constant rate with reduced shock and rebounding. Cable typically elongates to 90 percent of its potential, but is surrounded by braided sheath to absorb remaining energy should it break prematurely. Applications of arrester include passenger restraint in air and land vehicles, parachute risers, and ground snatch by aircraft. Possible cable material is type 302 stainless steel.
Wind tunnel tests recorded the effect of decelerators on flow at various supersonic speeds. Rigid parachute models were tested for the effects of porosity, shroud length, and number of shrouds. Flexible model parachutes were tested for effects of porosity and conical-shaped canopy. Ribbon dive brakes on a missile-shaped body were tested for effect of tension cable type and ribbon flare type. The final test involved a plastic sphere on riser lines.
For deepwater operations the self-propelled oil drillship is employed. This type of vessel resembles a cargo ship except for its large derrick, which supports the drilling equipment. Extending from the drillship to the well thousands of feet steel tube usually one to two feet in diameter. The drilling equipment, or drill string, is lowered to the well through this riser. The riser is not rigid nor strictly vertical; it is described by one expert as "a very long piece of spaghetti," held in tension at the well and at the ship end by strong cables. Obviously, the ship must remain often for months-in a position directly over the well. If it were to drift excessively forward, aft or to either side, its movement could snap the riser and disrupt operations at a cost of millions. That's where space technology is playing a part. The same technology employed to locate a spacecraft in orbit and maintain a precise position is applicable to drillship operation. In space, automatic navigation equipment sights on reference points-the Earth, the sun or other stars--to determine spacecraft location. If the space mission requires the spacecraft to hold a certain position, it is accomplished by the firing of computer- directed control thrusters. Two major aerospace companies- Honeywell Inc. and TRW Inc.-have applied their extensive experience in spacecraft positioning and control to the offshore drilling technique known as dynamic positioning, meaning holding the drillship in precise position over the work site.