The "BEST" Facility in AE
The Building Environment Simulation and Testing (BEST) Facility is a state-of-the-art installation designed for full-scale thermal and air quality research. It is managed by Dr. Jelena Srebric with the assistance of her students: Atila Novoselac (postdoctoral researcher), Danko Davidovic, Vladimir Vukovic (graduate students), and Reed Berinato, Brendon Burley, Matthew Keller, and Tracey Nawrocki (undergraduate students).
 |
| Figure 1. A schematic of climate and environmental chambers |
The facility consists of an environmental chamber and a climate chamber with two separate heating, ventilating, and air-conditioning (HVAC) systems. An important part of this facility is the sophisticated measuring and data acquisition system used for measurements of indoor air quality, energy and air flow parameters such as surface heat flux, surface and air temperatures, velocity, humidity, and tracer gas concentrations at various locations in the facility. The facility has been designed for maximum flexibility to encourage a wide variety of experimental research activities. Both the HVAC systems and the control systems are reconfigurable to permit alternative components, subsystems or even complete systems to be easily installed, modified, and tested.
The environmental chamber representing an indoor environment and the climate chamber simulating an outdoor environment are two integral components of the test facility (see Figure 1). Each room has its own air handling unit and can be independently controlled to simulate any type of environment. By changing the climate chamber conditions, one can measure the effects of those changes on the indoor environment. The primary purpose of the environmental chamber is to create various indoor environmental conditions, where certain groups of indoor parameters are controlled and other groups of parameters are measured. For example, for a certain ventilation strategy, a volume flow rate and temperature of supply air are controlled, while distribution of surface temperature, air velocity, air temperature, and tracer gas concentrations are measured. On the other hand, the primary purpose of the climate chamber is to simulate a wide range of outdoor weather conditions, from cold winters to hot summers. The two chambers are separated from each other by a partition wall with a window. To allow flexibility, the environmental chamber is equipped with a Unistrut System that can be used to support additional structures inside the chamber. This system allows the insertion of additional "test boxes" or the separation of the chamber into smaller volumes.
 |
| Figure 2. An outside view of the BEST facility and acquisition equipment. |
The measuring equipment is intended mainly for use within the environmental and climate chambers, but it can also be used for onsite applications. The equipment is divided into three main groups of data acquisition systems: Air Low Velocity and Temperature Measurement System (based on omnidirectional thermo-anemometer sensors that can be used to take air temperature and low air velocity measurements in rooms and inside air supply devices), Air and Surface Temperature Measurement System (for precise measurement of surface and air temperatures, and the Tracer Gas Testing System (to determine airflow and contaminant movement in complex situations). Besides these three main systems, surface heat flux meters, a hydronic calorimeter, air flow stations, and an electric power meter are employed.
Several research projects have been conducted in the BEST facility. These projects included: (1) development and evaluation of numerical models for indoor contaminant distribution simulations; (2) development of surface convection correlations for room enclosures with different ventilation strategies, and (3) validation of newly developed models for thermal boundary conditions in computational fluid dynamics (CFD) programs.
 |
| Figure 3. Several members of Dr. Srebric’s research group around a human simulator inside of the environmental chamber (L-R: Reed Berinato, Dr. Jelena Srebric, Tracey Nawrocki, and Atila Novoselac). |
A current project is a two-year collaboration between the Architectural Engineering and Horticulture departments to determine the thermal transmission properties of green roofs. This is a challenging task because even though American Society for Testing and Materials (ASTM) has outlined two primary methodologies for testing insulation materials, neither could be applied to green roofs due to their non-homogenous nature and the possibility of significant internal flows of air and water. Highly sensitive devices in the BEST environmental chamber monitor the energy flow through the building envelope specimens and measure air and surface temperatures above and below the specimens. The experiments will include not only the testing of thermal transmission through green roofs at different environmental conditions, but test results will also be used to develop a new test procedure. Currently, tests for thermal properties of strawbale walls are under way. All of these testing of sustainable building materials could have exciting impacts in the future analysis and design of buildings.
The BEST facility was completed in 2004 using funding from Penn State University and equipment donations from the HVAC industry. It is located at the University Park Campus in the basement of Engineering Unit A - a convenient location for students, researchers and visitors.
More details about the BEST facility and ongoing research projects can be found at the following web page: www.engr.psu.edu/jsrebric/facility.html.