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Building and Fire Research Laboratory Large-Scale Structural Testing Facility Building Integrated Photovoltaic Testbed |
Research Facilities Large-Scale Structural Testing Facility The NIST large-scale structural testing facility consists of a universal testing machine (UTM) that may be used in combination with a 13.7-meter tall reaction buttress and horizontal hydraulic ram to apply tension or compression and lateral forces to large-scale specimens. Capabilities: The UTM portion of the facility is a servo-controlled, hydraulically operated machine. With a capacity of 53.4 meganewtons and a height of 23.7 meters, it is one of the largest in the world. It can be programmed by function generator or computer to create any desired loading function using force, strain, or displacement as the variable. It tests large structural components and subassemblies and applies the forces needed to calibrate large capacity force-measuring devices. It can apply two-compression forces to test sections up to 18 meters in height. The reaction buttress can resist horizontal forces up to 4.5 meganewtons from floor level to a height of 12.2 meters. Tension specimens may be subjected to forces up to 26 meganewtons. A 2-meter-thick test floor may be used to hold specimens in place. Applications: A research program was conducted to evaluate the performance of concrete columns 1.5 meter in diameter and up to 9.1 meters in height. Another study evaluated fracture propagation in 1-meter-wide steel plates with thickness of 100 millimeters and 150 millimeters. A third project used the servo-control system to apply repeated loads to fiber-reinforced composite specimens. We can use this facility for low-cycle fatigue tests, destructive or proof load testing, earthquake simulation in two dimensions, and complex loading of components. Servo operation of this machine creates a unique potential for applying precisely controlled, large forces to test components. Availability: This facility, which NIST staff must operate, is available for cooperative or independent research. Tests should be arranged as far in advance as possible as special hardware may be needed for attaching specimens. Contact: Shyam Sunder The tri-directional test facility at NIST is a computer-controlled apparatus capable of applying cyclic loads simultaneously in three directions. It is used to examine the strength and deformation characteristics of structural components or assemblages under the application of a variety of loads, such as simulated effects of earthquake or wind. This is one of the largest facilities of its kind in the United States in terms of both load capacity and specimen size. Capabilities: The facility can apply forces or displacements, or both, in six directions. Specimens up to 3.3 meters in height and 3 meters in length or width may be tested. The six degrees of freedom are translations and rotations in and about three orthogonal axes. Six closed-loop, servo-controlled hydraulic actuators apply forces or displacements. Loads up to 2,000 kilonewtons may be applied in the vertical direction and about 890 kilonewtons in each of the two horizontal directions. The control and data acquisition systems have been updated to increase the machine's capabilities and to simplify its operation. Applications: Loads may be cyclic or monotonic depending on the type of loading condition being simulated. The facility is used to study masonry shear walls subjected to reverse cyclic lateral loading and precast concrete beam column and wall connections, also subjected to reverse cyclic lateral loading. This facility supports our role in conducting research for the development of seismic design and construction standards in the National Earthquake Hazards Reduction Program. Availability: The tri-directional test facility is used by NIST staff in a variety of NIST research projects and in collaborative projects with other agencies. It also is available for independent research but must be operated by NIST staff. Contact: Shyam Sunder NIST operates several environmental chambers capable of simulating a variety of temperature conditions. The largest chamber, referred to as the large truck chamber, measures 14.6 meters by 7.3 meters by 4.2 meters with a 3.6-meter by 3.6-meter access door. The heat pump chambers are located in adjacent rooms. Capabilities: The large truck chamber is capable of maintaining steady and dynamic temperature profiles from -45 to 65 degrees Celsius. Cooling and heating tests may be performed with dry-bulb and dew-point temperature control of ±0.1 degree Celsius. A maximum of 35 kilowatts of heat may be removed from this chamber at 35 degrees Celsius and 50 percent relative humidity. The heat pump chambers are designed for testing systems at standard cooling and heating conditions. The indoor chamber can maintain steady dry-bulb and dew-point conditions from 10 to 60 degrees Celsius, and the outdoor chamber can maintain temperatures from -18 to 60 degrees Celsius. The maximum capacity system for these chambers is 35 kilowatts. The appliance chamber may be controlled from -18 to 65 degrees Celsius with relative humidity controlled within ±2 percent. Maximum heat removal from this chamber is 12 kilowatts. Applications:
Testing of large equipment and special structures can be carried out
in the large truck chamber. It has been used to test the performance of
engines, vehicles, and special structures under extreme heat and cold.
The heat pump chambers are used to test residential heat pump and air-conditioning
equipment. The appliance chamber is used to test appliances and small
heating and cooling equipment such as radiators, heat exchangers, water
coolers, and control devices. Availability: These facilities are available to investigators from industry and universities, but must be operated by NIST staff. Collaborative research programs and proprietary research can be arranged. Contact: Piotr A. Domanski Building Integrated Photovoltaic Testbed NIST measures the long-term performance of building integrated photovoltaic panels in-situ using the Building Integrated Photovoltaic Testbed. The facility provides comparison between different building integrated photovoltaic panels when exposed to identical meteorological conditions. Up to nine panels can be evaluated simultaneously. We can compare energy production, operating temperature, heat flux, and characteristic current versus voltage curve traces. This testbed consists of crystalline, polycrystalline, amorphous, and silicon film building integrated photovoltaic products. Two identical panels of each photovoltaic cell technology, one insulated and one un-insulated, are currently installed. Meteorological instrumentation includes two precision spectral pyranometers, one precision infrared radiometer, and two radiatively shielded type-T thermocouples. An ultrasonic wind sensor is used to measure the magnitude and direction of air movement in a vertical plane. Two systems are used to monitor the Building Integrated Photovoltaic testbed. A testbed data acquisition system is used to measure the output signals of the outdoor meteorological instruments, the heat flux transducers, the panel temperature sensors, and two radiatively shielded indoor ambient temperature sensors. This data acquisition system scans the sensors and records the data every five minutes. The second data acquisition system is a custom built photovoltaic measurement system, referred to as a multi-tracer. The multitracer simultaneously loads and collects electrical performance data on multiple photovoltaic panels. The multi-tracer can operate with a maximum of 14 panels. Capabilities:
The testbed is capable of evaluating up to nine building integrated
photovoltaic panels simultaneously. The size of the panels can vary up
to a maximum of 1.38 meters by 2.36 meters. The multi-tracer can dissipate
up to 2,400 watts. User selectable load options include: peak power tracking,
fixed voltage operation, user specific voltage profile, and unloaded or
open circuit. Contact: A. Hunter Fanney NIST's mobile solar tracking facility is used to characterize the electrical performance of photovoltaic panels. It incorporates meteorological instruments, a solar spectroradiometer, a data acquisition system, and a single-channel photovoltaic curve tracer. Precision spectral pyranometers are used to measure total (beam plus diffuse) solar radiation. We use two instruments to provide redundant measurements. We use a pyrheliometer to measure the beam component of solar radiation and measure long-wave radiation, greater than 3 micrometers, using a precision infrared radiometer. A three-cup anemometer assembly measures wind speed. We measure the ambient
temperature using a thermocouple sensor enclosed in a naturally ventilated
multiplate radiation shield. Capabilities: The mobile solar tracking facility can be operated in the following tracking modes:
Up to four photovoltaic
modules can be mounted on the facility simultaneously. The facility can
be operated over an azimuth range of ± 135° and over an elevation
range from horizontal to vertical. Availability: This apparatus may be available for use by those outside NIST, but it must be operated by BFRL staff. Collaborative programs may be arranged on a cost reimbursable basis. Contact: A. Hunter Fanney Line Heat-Source Guarded Hot Plate The 1-meter guarded hot-plate apparatus measures thermal conductivity of building insulation. This facility provides for absolute measurement of thermal resistance of thick and low-density test specimens used as transfer standards. These standards are used to calibrate heat-flow-meter apparatus or verify guarded-hot-plate apparatus. This facility is the only one of its kind in the world that will permit low-density thick insulation to be measured with an expanded uncertainty of less 1 percent. Capabilities: Laboratory services for thermal resistance measurements and related thermal properties are provided for thermal insulation and building materials having thermal conductivities of 0.02 to 0.15 watt per meter kelvin. In general, the highest accuracy is obtained for homogeneous specimens. The preferred size for the test specimen is 1,016 millimeters in diameter; the minimum size, 610 millimeters square. Customers can supply their own material for specimens, or request NIST to select specimens from an in-house inventory of fibrous-glass material. All tests are performed at an ambient atmospheric pressure of approximately 100 ± 20 kilopascals (site pressure at Gaithersburg, Md.). Services at ambient pressures outside these limits or with other gases are not provided. A dry-air purge is available to reduce the relative humidity to less than 15 percent. Availability: This apparatus is available for use by those outside NIST, but it must be operated by BFRL staff. Collaborative programs may be arranged on a cost reimbursable basis. Contact: Robert R. Zarr NIST recently opened its newly renovated Large Fire Facility for measuring and quantifying the response of basic materials, assembled products, and structures in fires up to 10 megawatts peak heat release. These measurements will be used to validate the predictions of practical and scientific fire models and to serve the unique fire research needs of industry, standards making bodies and other government agencies. Laboratory services include protected areas for safely burning materials and objects without releasing smoke to the environment; state of the art heat release rate measurements with documented uncertainty; a Labview-based data system that acquires and displays, in close to real time, the exhaust flow, heat release history, and critical temperatures in the area of the fire; video records of the experiments synchronized to the heat release measurement; and communications among a range of standard and specialized instruments to meet the objectives of a particular experiment (e.g., smoke meter, mass loss from burning object, radiation distribution, local heat flux, velocity field around fire, extractive and in situ gas and particulate measurements, suppressant flow and droplet characterization). The facility has a large 27- by 5-meter open area designed to accommodate a wide variety of structures. Four exhaust hoods ranging in size from 1 to 80 square meters are equipped with heat-release-rate calorimeters to cover fires from a small single burning object to a fully flashed-over room. We plan to add the capability to examine wind-aided fires. A standard ISO 9705 burn room or a custom structure can be constructed. The full-scale performance of fire detection and suppression systems can be measured in the Large Fire Facility or in unique smaller scale laboratories. Our fire-emulator/detector-evaluator has been specially designed to enable the development of new fire detection systems and to measure their performance against alternative technologies. A suite of nuisance sources (e.g., organic aerosols, cigarette smoke, inorganic dust, cooking foods, steam, gases) have been quantified to see how well a particular design can discriminate a flaming or smoldering fire from a non-fire event. We have developed fire suppression screening devices to evaluate the performance of non-traditional halon alternatives. Our dispersed liquid agent fire suppression screening apparatus can compare the effectiveness of a firefighting agent that exists in liquid phase at room temperature to that of halon 1301, providing a performance measure for liquid agents that is equivalent to cup burner performance measures for gaseous agents. We have developed the transient application recirculating pool fire apparatus to examine the performance of solid-propellant gas generators and enable manufacturers and users of this technology to evaluate proposed improvements in propellant composition or discharge design. Heat flux transducers used for determining convective and/or radiative heat transfer are a critical part of any measurement of the response of a material to fire. We have developed a special Convective Heat Flux Facility for characterizing transducers by subjecting them to a purely conductive or convective flow traceable to the NIST radiometric source. Availability: Industry, university, and government representatives are encouraged to contact NIST regarding the use these fire measurement facilities in a collaborative or independent basis. Contact: William Grosshandler
Date
created:
April 24, 2002 |