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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

Impact of Balance Of System (BOS) costs on photovoltaic power systems

The Department of Energy has developed a program to effect a large reduction in the price of photovoltaic modules, with significant progress already achieved toward the 1986 goal of 50 cents/watt (1975 dollars). Remaining elements of a P/V power system (structure, battery storage, regulation, control, and wiring) are also significant cost items. The costs of these remaining elements are commonly referred to as Balance-of-System (BOS) costs. The BOS costs are less well defined and documented than module costs. The Lewis Research Center (LeRC) in 1976/77 and with two village power experiments that will be installed in 1978. The costs were divided into five categories and analyzed. A regression analysis was performed to determine correlations of BOS Costs per peak watt, with power size for these photovoltaic systems. The statistical relationship may be used for flat-plate, DC systems ranging from 100 to 4,000 peak watts. A survey of suppliers was conducted for comparison with the predicted BOS cost relationship.

Hein, G. F.↗
NASA NTRS2014

Visualization of Flow Separation Around an Atmospheric Entry Capsule at Low-Subsonic Mach Number Using Background-Oriented Schlieren (BOS)

This paper presents the results of visualization of separated flow around a generic entry capsule that resembles the Apollo Command Module (CM) and the Orion Multi-Purpose Crew Vehicle (MPCV). The model was tested at flow speeds up to Mach 0.4 at a single angle of attack of 28 degrees. For manned spacecraft using capsule-shaped vehicles, certain flight operations such as emergency abort maneuvers soon after launch and flight just prior to parachute deployment during the final stages of entry, the command module may fly at low Mach number. Under these flow conditions, the separated flow generated from the heat-shield surface on both windward and leeward sides of the capsule dominates the wake flow downstream of the capsule. In this paper, flow visualization of the separated flow was conducted using the background-oriented schlieren (BOS) method, which has the capability of visualizing significantly separated wake flows without the particle seeding required by other techniques. Experimental results herein show that BOS has detection capability of density changes on the order of 10(sup-5).

Mizukaki, Toshiharu↗
NASA NTRS2013

Background Oriented Schlieren (BOS) and other Flow Visualization Developments and Applications at GRC

This is a presentation to be given at an internal NASA Advanced Schlieren Working Group Meeting. The presentation will cover the recent developments and applications of flow visualization methods at GRC. The topics being discussed will include the use of Background Oriented Schlieren (BOS) in the study of screech and its associated shock spacing as well as in the investigation of broadband shock noise reduction in the Jet-Surface Interaction Tests. In addition, other flow visualiztion methods will be discussed in an on-going study comparing schlieren, shadowgraph, BOS, and focusing schlieren.

background oriented schlieren↗
DOE OSTI2020

Materials Data on BOs by Materials Project

BOs is Tungsten Carbide structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Os3+ is bonded to six equivalent B3- atoms to form a mixture of distorted corner, edge, and face-sharing OsB6 pentagonal pyramids. All Os–B bond lengths are 2.21 Å. B3- is bonded to six equivalent Os3+ atoms to form a mixture of distorted corner, edge, and face-sharing BOs6 pentagonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2021

HybridBOSSE (Hybrid Balance-of-System (BOS) Systems Engineering Model)

Hybrid Power Plants (HPPs) have the potential to increase the value of renewable energy systems and decrease their costs through shared development (e.g., permitting) and infrastructure (e.g., collection system). Prior work has identified potential cost savings and technical and economic performance improvements for solar plus storage plants. However, additional research is needed to understand cost drivers that are specific to hybrid wind plants. Here we analyze the potential for shared infrastructure cost savings at one type of hybrid plant: wind plus solar photovoltaic (PV). To perform this analysis, we developed a new open-source, Python-based cost modeling tool: the Hybrid Balance-of-System (BOS) Systems Engineering model (HybridBOSSE). HybridBOSSE is an extension of NREL's LandBOSSE tool.

Barker, Aaron↗
NASA NTRS2016

Background Oriented Schlieren (BOS) of a Supersonic Aircraft in Flight

This presentation describes the development and use of Background Oriented Schlieren (BOS) on a full-scale supersonic jet in flight. A series of flight tests was performed in October 2014 and February 2015 using the flora of the desert floor in the Supersonic Flight Corridor on the Edwards Air Force Base as a background. Flight planning was designed based on the camera resolution, the mean size and color of the predominant plants, and the navigation and coordination of two aircraft. Software used to process the image data was improved with additional utilities. The planning proved to be effective and the vast majority of the passes of the target aircraft were successfully recorded. Results were obtained that are the most detailed schlieren imagery of an aircraft in flight to date.

Visualization↗
DOE OSTI2020

Materials Data on Nd(BOs)4 by Materials Project

Nd(OsB)4 is alpha Pu-derived structured and crystallizes in the tetragonal P4_2/n space group. The structure is three-dimensional. Nd2+ is bonded in a 8-coordinate geometry to eight equivalent Os2- atoms. There are four shorter (3.22 Å) and four longer (3.23 Å) Nd–Os bond lengths. Os2- is bonded in a 4-coordinate geometry to two equivalent Nd2+ and four equivalent B+1.50+ atoms. There are a spread of Os–B bond distances ranging from 2.14–2.19 Å. B+1.50+ is bonded in a 4-coordinate geometry to four equivalent Os2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(BOs)2 by Materials Project

Pr(OsB)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Pr3+ is bonded in a 4-coordinate geometry to four equivalent Os+1.50- atoms. All Pr–Os bond lengths are 3.06 Å. Os+1.50- is bonded in a 4-coordinate geometry to two equivalent Pr3+ and four equivalent B atoms. There are two shorter (2.10 Å) and two longer (2.18 Å) Os–B bond lengths. B is bonded to four equivalent Os+1.50- atoms to form a mixture of distorted corner and edge-sharing BOs4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce(BOs)2 by Materials Project

CeOs2B2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Ce3+ is bonded in a 4-coordinate geometry to four equivalent Os+1.50- atoms. All Ce–Os bond lengths are 3.01 Å. Os+1.50- is bonded in a 4-coordinate geometry to two equivalent Ce3+ and four equivalent B atoms. There are two shorter (2.09 Å) and two longer (2.17 Å) Os–B bond lengths. B is bonded in a 4-coordinate geometry to four equivalent Os+1.50- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La(BOs)2 by Materials Project

La(OsB)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. La3+ is bonded in a 4-coordinate geometry to four equivalent Os+1.50- atoms. All La–Os bond lengths are 3.06 Å. Os+1.50- is bonded in a 4-coordinate geometry to two equivalent La3+ and four equivalent B atoms. There are two shorter (2.11 Å) and two longer (2.18 Å) Os–B bond lengths. B is bonded to four equivalent Os+1.50- atoms to form a mixture of distorted edge and corner-sharing BOs4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(BOs)2 by Materials Project

Th(OsB)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Th4+ is bonded in a 4-coordinate geometry to four equivalent Os2- atoms. All Th–Os bond lengths are 3.04 Å. Os2- is bonded in a 4-coordinate geometry to two equivalent Th4+ and four equivalent B atoms. There are two shorter (2.10 Å) and two longer (2.18 Å) Os–B bond lengths. B is bonded to four equivalent Os2- atoms to form a mixture of distorted edge and corner-sharing BOs4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U(BOs)4 by Materials Project

U(OsB)4 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional. U6+ is bonded in a 12-coordinate geometry to twelve equivalent Os+1.50- atoms. There are a spread of U–Os bond distances ranging from 2.93–3.27 Å. Os+1.50- is bonded in a 5-coordinate geometry to three equivalent U6+ and five equivalent B atoms. There are a spread of Os–B bond distances ranging from 2.16–2.28 Å. B is bonded in a 6-coordinate geometry to five equivalent Os+1.50- and one B atom. The B–B bond length is 1.77 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nd(BOs)2 by Materials Project

Nd(OsB)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Nd3+ is bonded in a 4-coordinate geometry to four equivalent Os+1.50- atoms. All Nd–Os bond lengths are 3.05 Å. Os+1.50- is bonded in a 4-coordinate geometry to two equivalent Nd3+ and four equivalent B atoms. There are two shorter (2.10 Å) and two longer (2.18 Å) Os–B bond lengths. B is bonded to four equivalent Os+1.50- atoms to form a mixture of distorted edge and corner-sharing BOs4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd(BOs)2 by Materials Project

Gd(OsB)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Gd3+ is bonded in a 4-coordinate geometry to four equivalent Os+1.50- atoms. All Gd–Os bond lengths are 3.02 Å. Os+1.50- is bonded in a 4-coordinate geometry to two equivalent Gd3+ and four equivalent B atoms. There are two shorter (2.08 Å) and two longer (2.18 Å) Os–B bond lengths. B is bonded in a 4-coordinate geometry to four equivalent Os+1.50- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2026

BOS Gas Detection Pipeline (Integrated System for Optical Hydrogen Detection Using Background Oriented Schlieren and Machine Learning) [SWR-26-007]

This software is the world's first integrated background oriented schlieren and machine learning-based leak detection system. The system provides real time visualization of gas leaks and machine learning interpenetration of leak severity. The software is supplemented by SWR-25-177, "gpu_piv (Graphics Processing Unit Accelerated Background Oriented Schlieren Algorithm", also developed by the National Laboratory of the Rockies. SEE DOECODE ID 182832.

Palin, Ian [National Laboratory of the Rockies (NL↗
NASA NTRS2016

Background Oriented Schlieren (BOS) of a Supersonic Aircraft in Flight

This article describes the development and use of Background Oriented Schlieren on a full-scale supersonic jet in flight. A series of flight tests was performed in October, 2014 and February 2015 using the flora of the desert floor in the Supersonic Flight Corridor on the Edwards Air Force Base as a background. Flight planning was designed based on the camera resolution, the mean size and color of the predominant plants, and the navigation and coordination of two aircraft. Software used to process the image data was improved with additional utilities. The planning proved to be effective and the vast majority of the passes of the target aircraft were successfully recorded. Results were obtained that are the most detailed schlieren imagery of an aircraft in flight to date.

Schlieren imaging↗
NASA NTRS2016

Comparison of Cross Correlation and Optical Flow Methods for Processing Retroreflective and Natural Background BOS Data

Background oriented schlieren images have historically been generated by calculating the observed pixel displacement between an image pair using normalized cross-correlation methods. This work uses optical flow data reduction methods to solve the displacement fields. A well established method used in the computer vision community, optical flow is the apparent brightness motion in an image sequence. The regularization method of Horn and Schunck is used to create schlieren images using two data sets: a supersonic shockjet plume interaction at the NASA Ames Unitary Plan Wind Tunnel, and a transonic flight test of a T-38 using a naturally occurring background performed in conjunction with NASA Ames and Armstrong research centers. Results are presented and contrasted with those using normalized cross-correlation methods. The optical flow images are found to provided significantly more detail at a decreased computational time.

schlieren↗