The fire emulator/detector evaluator (FE/DE) is a computer-controlled flow tunnel used to re-create the environments surrounding detectors in the early stages of fire and background environments that give rise to false alarms. The flow velocity, temperature, humidity, carbon monoxide, carbon dioxide, and hydrocarbon gas concentration, and smoke or nuisance aerosol concentration are controlled to emulate burgeoning fire conditions or nuisance sources. The input controls may be obtained from full-scale fire experiments, computer fire models, or heuristic formulations.
Specifications / Capabilities:
The FE/DE can provide control of the flow velocity over a range from 2 cm/s to over 1.5 m/s. Temperature change is achieved by feedback controlled electrical heating elements with maximum temperatures exceeding 80oC depending on the flow velocity. Carbon monoxide, carbon dioxide, and hydrocarbon gas concentrations are independently controlled via electronic mass flow controllers. Black smoke is generated by a propane diffusion flame burner with smoke concentration controlled by fuel flow and the damper control from the burner to the FE/DE duct. Smokes from cotton smolder and wood pyrolysis represent smolder smoke sources. Nuisance sources include cooking activities, tobacco smoke, humidity and condensing water vapor, and dusts. Routine measurements at the detector location include light extinction, temperature, flow velocity, combustion gas concentrations, and water concentration. Detailed measurements of the aerosol number and mass concentration, and size distribution measurements are possible along with detailed 2-D velocity measurements around detector housings with a 2 component LDV.
Scientific Opportunities / Applications:
The FE/DE is being used in ongoing research concerning low air speed smoke entrance effects in detectors, test and evaluation methodologies for multi-sensor fire detection, modeling of detector output to support real-time computing of building fire environments, development of algorithms for multi-sensor, multi-function detectors, and emulation of aircraft cargo compartment fire conditions to evaluate current and improved detector designs.
The facility is used in a variety of EL research projects and collaborative projects with other agencies. It also is available on a cost reimbursable basis for independent research but must be operated by EL staff.