Impacts of Non-Isothermal Task Conditioning System with Individual Control on Thermal Comfort and Productivity

Subjective experiments with a non-isothermal task conditioning system were conducted toinvestigate impacts of the system on thermal comfort and productivity in a climate chamber of Kanto-Gakuin University, Japan. All subjects participated in "default condition test: 26C / 50% RH" at first.Then a half of the same subjects participated in "standard condition test: 26C / 50% RH", and theremainder subjects participated in "task-ambient test: 30C / 50% RH + TAC", just one week later again separately. Thermal, humidity, comfort sensations, and other psychological factors were investigated.

Air quality evaluation in the space with personalized ventilation and different occupant distributions

For the application of personalized (PV) in practice, it is important to recognize its performance under realistic conditions as they apply in rooms. In this paper results of both CFD simulations and laboratory measurements are reported regarding the local ventilation effectiveness with personalized ventilation. It was observed that the personalized air influences only a limited microenvironment at the workstation. Then a new model was proposed to evalate the indoor air quality in the entire space with varied distributions of occupants.

Interactive indoor air flow analysis using high performance computing and virtual reality techniques

In this article a prototype application of an interactive CFD-based computational steering system is presented, connecting a high performance computer (HPC) with a Virtual Reality (VR) environment. During the preliminary investigation of indoor air flow phenomena the user is able to interact on line, e.g. by modifying the geometry of the simulation scenario during the simulation itself. To allow for a comfortable analysis of complex fluid flow configurations a VR system consisting of a stereoscopic projection unit and a wand device is supported.

Local radiative heat transfer on a human body. Analyses through modelling

In the case of moderate climates, convective and radiative heat exchanges are the main avenues for heat losses on a human body. When using a dummy it is sometimes difficult to have a good estimation of the heat transfer coefficients for convection and/or radiation and especially to determine the part of each mode. It is now quite easy to calculate radiative transfer with accuracy. The approach proposed here, is to find a better estimation of the local radiative heat transfer through modeling and to discuss the value of local radiative coefficients in different situations.

Coupled Simulation of Convection and Radiation on Thermal Environment around an Accurately Shaped Human Body

The present study is directed toward an accurate analysis on the transport of sensible heat overa realistically shaped human body model by way of a coupled convection-radiation simulation technique. A low-Reynolds-number type k- e turbulence model is employed to obtain the convective heat flux distribution with greater accuracy. Configuration factors over the complex geometry are accurately calculated using a Monte-Carlo method incorporating symmetrization procedures.

Assessment of the Thermal Insulation of the Air Layer with a Movable Thermal Manikin

The assessment of the overall thermal insulation of the air shear layer surrounding a nude humanoid shape, as affected by different step rates, is the main objective of the present study. Step rateswere controlled at 0, 20, 30 and 45 steps/min. The measurements were carried out in a climate chamber with an articulated thermal manikin of the Pernille type with 16 body segments. In addition, the convective heat transfer coefficients for the 16 segments and for the whole body were determined for each step rate.

Evaluation of Input - Side Parameter of Productivity by Cerebral Blood Oxygenation Changes

To evaluate effect of indoor environment quality on productivity, the changes in cerebral bloodoxygenation by near infrared spectroscopy was examined. In this study, relationship between the changes in cerebral blood oxygenation and difficulty level of task was evaluated by subjective experiments. Four tasks were given to the subjects: single-digit addition, double-digit multiplication, triple-digit addition, and triple-digit multiplication. It was evaluated that the more difficult task types to solve, the more oxygenated hemoglobin and total hemoglobin concentration were needed.

Measurement of aerosol deposition in bifurcating ducts with curved inlet

The quantitative knowledge gained from the assessment of particle deposition in ducts is importantto study, for example, the elimination of air leakage from duct systems with aerosolized sealant particles or to implement strategies of cleanliness of air ventilation systems. The study of particle deposition on the components of ventilation systems contributes also significantly to a better understanding of human exposure to particulate pollution. In this work we investigate deposition of aerosol particles in bifurcating ducts with a curved inlet segment.

CFD Simulation of Air Distribution in Displacement Ventilated Rooms with a Moving Object

Numerical experiments by computational fluid dynamics (CFD) simulation were done toinvestigate air distribution in displacement ventilated rooms with a moving person, which affects thermal stratification of indoor air required for controlling and maintaining good air quality and high efficient ventilation performance. The distributions of indoor air and ventilation effectiveness obtained by the simulation were compared with the experiments using a full-scale room model.

Measured occupancy levels in Swedish offices

In order to accurately design and analyze demand controlled volume ventilation systems, theoccupancy level in the room must be known. The occupancy level corresponds to the length of time people occupy a room. Since there is a lack of data for occupancy levels in regards to offices, this study reports on measured occupancy levels for three cell offices in Sweden. The same occupancy sensors were used as those found on the ventilation systems. The results showed that the occupancy level for an office was as low as 11.2%.

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