The paper deals with a research about analytical techniques for meaningful, reliable, cost-effective, in-situ, real-time and continues determination of airborne chemicals, by means of a new electrochemical sensor; the research aims to develop objective instrumental sensing systems able to substitute the subjective human responses. Sensor detection capability could regard a series of analytes: carbon dioxide, carbon monoxide, inorganic pollutants, ammonia and other metabolic gases, irritants, odours.
Assessing the perceived air quality in decipols by trained panels can be performed rather perfectly today. To calculate the olf load from these results is a little more problematic as one requires olf loads which can simply be added (linearly). The reason for this difficulty is the nonlinear relation between the perceived air quality in decipol and the pollution load in olf. The relation can be expressed by an exponential function in a range between l to 15 decipols. Unfortunately the exponent and the constant in the exponential function differ for different substances.
This paper considers methodologies how desired level, target level, of industrial air quality can be defined taking into account a feasibility issue. The method is based on the health-based risk assessment and the technology-based approach. Because health-based risk estimates at low contaminant concentration regions are rather inaccurate, the technology-based approach is emphasized. The technological approach is based on information on the prevailing contaminant concentrations in industrial work environment and the benchmark air quality attained with the best achievable control technology.
This paper presents a set of detailed experimental data of room airflow with displacement ventilation. These data were obtained from a new environmental test facility at the Massachusetts Institute of Technology (MIT). The measurements were conducted for three typical room configurations: a small office, a large office with partition, and a classroom. The experiment measured the distributions of air velocity, air velocity fluctuation, and air temperature by omnidirectional hot-sphere anemometers and contaminant concentrations by tracer gas at 54 points in the room.
In the unsteady calculations of room thermal environments, two simple and effective methods were introduced to reduce computer efforts through two case studies. One method (method-A) was applied to a passive solar room analysis (caseA) and another method( method-B) was applied to estimation of energy consumption in an air-conditioned room (caseB). In method-A, flow fields are calculated intermittently, namely, calculated every Nta time step while temperature fields are calculated every time step here, Nta≥ 1.
To evaluate the performance of different turbulence models in room airflow applications measurements in a test room will be compared to numerical calculations. The measurements are taken in a 6 x 4 x 3 m3 room with two heated dummies and a computer. Zero heat flux boundary conditions are achieved by controlling the inner and outer wall temperature. Two different ventilation systems will be examined in order to get momentum and buoyancy driven flow fields. Temperature measurement and Particle Streak Tracking data will be compared to the numerical predictions.
An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution will be introduced for improvement of the predictions of both the energy consumption and the indoor environment. The building energy performance simulation program requires a detailed description of the energy flow in the air movement which can be obtained by a CFD program.