Chamber Equipment
The Building Energy and Environmental System Facility is composed of two chambers.
- Indoor Environmental Chamber
- Outdoor Climate Chamber
The chamber's walls are constructed with R-30 insulation and coated with galvanized steel on both sides to protect against external influences. There is a partition wall with a sliding window which divides the climate and environmental chambers.
To further allow flexibility the environmental chamber is equipped with a Unistrat 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 as with a suspended ceiling.
Each of the chambers has a separate Air Handling Unit (AHU) capable of simulating various environmental conditions. Both AHUs have a pre-filter and a hepa filter which together provide 95% cleaning of Outdoor Air.
In addition to the separate AHUs, a Hydronic Cooling and Heating System has been furnished. This system provides hot and chilled water for HVAC subsystems that can be installed within the chambers. Examples include radiant heating or cooling panels and fan coil systems.
Environmental Chamber
20' x 13' x 9' in size and capable of simulating indoor air conditions, including air temperature, relative humidity, volume flow rate, and room air distribution.
Air Handling Unit
| Airflow: | Up to 20 ACH and 100% OA. |
| Heating Capacity: | 70,000 BTU/hr |
| Cooling Capacity: | 40,000 BTU/hr |
| Humidifying Capacity: | xx lb/hr |
| Flow Variation: | Larger of ±5% set value or ±5% volume flow rate |
| Return Air Temperature Variation: | ±.8°F in 50°F-95°F range |
| Return Air Relative Humidity Variation: | ±5% RH in 30% RH-80% RH range |
Climate Chamber
8' x 13' x 9' in size and capable of simulating a variety of outdoor weather conditions. The variability can simulate cold dry winters as well as hot and humid summers. The controllable factors are air temperature, relative humidity, and wind pressure.
Air Handling Unit
| Airflow: | Up to 40 ACH and 100% OA. |
| Heating Capacity: | 70,000 BTU/hr |
| Cooling Capacity: | 40,000 BTU/hr |
| Humidifying Capacity: | xx lb/hr |
| Flow Variation: | Larger of ±5% set value or ±5% volume flow rate |
| Return Air Temperature Variation: | ±1°F in 14°F-104°F range |
| Return Air Relative Humidity Variation: | ±5% RH in 30% RH-80% RH range |
Hydronic Cooling and Heating System
| Water Flow Rate: | Up to 4 gpm |
| Heating Capacity: | 15,000 BTU/hr |
| Cooling Capacity: | 20,000 BTU/hr |
| Supply Water Temperature: | 41°F-194°F |
| Water Flow Variation: | ±1% set value |
| Supply Temperature Variation: | ±.6°F in 41°F-194°F range |
Both the AHU cooling coils and the hydronic cooling system utilize a chilled glycol solution which gives the chiller an R22 working fluid and a 10 ton capacity. A 50% glycol solution is used to provide cooling below the freezing point of water within the climate chamber.
The Central Allen Bradley Automatic Control System controls the following systems:
- Chiller Control Loops
- AHU Control Loops
- Hydronic Cooling and Heating System Control Loops
Chiller Control Loop
The chiller capacity is controlled by regulation of the number of active cylinders of reciprocating compressor and by limiting the amount of refrigerant vapor that passes from the compressor exhaust to the evaporator inlet.
AHU Control Loops
Both chambers have the following three basic control schemes:
- Constant air flow rate, constant supply temperature
- Constant supply temperature, variable flow rate (VAV system)
- Variable supply temperature, constant flow rate
Control scheme one is intended for steady state measurements or for control of the supply air parameters when the load is regulated by fan coil or radiant systems. Control schemes two and three are intended for measuring when variable loading is present. In a VAV system the partition window must be closed to prevent interaction between the air handling units and ensure stable control.
It is possible to reconfigure the control system (sensor distribution) and program the system for research of alternative control strategies or new and unconventional HVAC systems.
Hydronic Cooling and Heating System Control Loops
There are three control schemes available:
- Constant water flow rate, constant supply temperature
- Constant supply temperature, variable water flow rate
- Variable supply temperature, constant flow rate
Similar to the AHU control loops, scheme one is intended for steady state measurements and schemes two and three are for variable loads.