Characterization of airflows at the exit of registers using laser doppler velocimetry (LDV)

This paper reports the results of fluid flow measurements carried out at the exit of sidewall registers. Time-averaged mean velocity and turbulence (local root mean square velocity fluctuation) profiles were measured at the exit plane of two commonly used 8 in. 4 in. (203 mm 102 mm) sidewall registers.

Individual control of air velocity for increasing productivity

Subjective experiments were conducted in a climatic chamber to evaluate the effect ofindividual control of air velocity on productivity. For the condition of constant air velocity(CAV) subjects were not allowed to control air velocity and for the condition of preferred airvelocity (PAV) they were allowed to control it. The chamber was conditioned at airtemperatures of 31C, mean radiant temperature of 31C, and relative humidity of 50%. Severalcomputer tasks were given to the subjects to evaluate task performance.

Survey of indoor air quality in three indoor swimming pools

The survey concerned three swimming pools using a similar type of basic water treatment, buthaving different structures and ventilation systems. The survey included measuring air currentvelocities above the pools and studying the microbiological and physico-chemical quality ofthe pool water. In addition, microbes were determined from the indoor air, structures andventilation systems, and airborne particles and volatile organic compounds from the indoor airsamples. The total particle concentration of the indoor air and their size distribution variedbetween the swimming pools.

Experimental study on unsteady air terminal

This paper describes the unsteady terminal and presents its characteristics gained fromexperiment. The experimental results showed that the fan-coil unit tested in the experimentwas able to provide fluctuating airflow and the velocity curve of supply airflow wasconsistent with the control signal very well. The spectrum of supply airflow is similar to thespectrum of natural wind if the control signal simulating natural wind provided. The supplyair temperature is changed when the airflow is changed.

Influence of geometry of thermal manikins on room airflow

A number of different thermal manikins have been applied in literature to experimentallystudy the indoor environment. These manikins differ in size, shape and level of geometriccomplexity ranging from simple box or cylinder shaped thermal manikins to humanlikebreathing thermal manikins. None of the reported studies, however, deals with the influenceof geometry of the thermal manikin.

A statistical approach to the evaluation of the maximum velocity within the occupied zone

Currently, a design of the maximum velocity stress in the occupied zone is based on applicationof the jet theory equations or on the data from the manufacturers catalogue. However, thesemethods are based on the idealized test conditions in empty rooms and do not necessarily predictthe conditions existing in realistic rooms with heat sources and sinks. Furthermore, little data isavailable of the distributions inside the occupied zone. A new statistical method for occupiedzone maximum velocity prediction is introduced and verified using experimental data.

The effect of temperature and air velocity change on human sensation

This report is a part of a study to search whether comfort conditions can be attained by localairflow. In the present experiment, local airflow was directed to two locations of subjectsbody and its effect was examined on which location percepts the airflow more strongly,responds physiologically more sensitively and feels more comfortable. The laboratory airtemperature was set in a range of 26-28C. This experiment was held in summer seasons atToyohashi, Japan.

Research on the effect of air velocity on thermal comfort based on the ramp changing transient environment

By simulating ‘the ramp change of thermal environment’ in the laboratory, we carried out the thermal comfort experiment and observed the changes of subjects' thermal reaction to the ramp change. We compared the effect of air velocity on the change of subj

Calculation of the room velocity using kinetic energy balance

For a long time, scientific research has tried to establish the relationships between jet momentum and room velocities. The final breakthrough is still to come. One approach is to use a kinetic energy balance, which was initially suggested by Elterman (1980). This paper presents a thorough kinetic energy analysis. Based on the analysis, a new method is developed for calculating the average room velocity. The calculation method is evaluated with the experimental date from laboratory experiments with three different air distribution methods.

Numerical and experimental studies on room airflow

In this study, the air flow in a small scale industrial hall is simulated numerically using two different computing codes, the commercial flow solver with a high-Reyholds number turbulence model and a university code with a low-Reynolds number turbulence model. The results are compared with measurements. Two different air supply arrangements with grille or nozzle types of air terminal devices are studied, both with isothermal and non-isothermal boundary conditions.