The aim of this research is to develop a new human model to predict mean skin temperature for evaluating hot outdoor environments. The model considers effects of solar radiation, sweat efficiency and wet clothing. The effect of solar radiation is given as a "solar operative temperature" defined as a function of net solar radiation absorbed on the surfaces of the skin and clothing after multiple reflections. We have measured solar transmittance and reflectance of some clothing of white T-shirt, navy blue shorts and grey T-shirt in an outdoor environment. A series of experiments using collage age subjects wearing the clothing of white T-shirt and navy blue shorts described above has been conducted outdoors with solar radiation, and mean skin temperatures were measured. Comparison is made between mean skin temperatures of those predicted from the model developed by the authors and those obtained by experiments. It is shown that the new model is valid to predict mean skin temperature in a hot outdoor environment within 0.5K accuracy.

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Air-conditioning systems with breeze-line type outlets are frequently adopted for perimeter zones in intelligent office buildings. However, it is pointed out that several examinations are required for the establishment of design criteria on position and shape of the outlet. The purpose of this study is to establish design criteria for breeze-line type air outlets adopted for perimeter zone in office buildings during winter season. In the previous report we described excellent thermal environment is not necessarily obtained in breeze-line type air outlet of summer in winter. In this report, we measured five kinds of thermal environmental index under four kinds of air supply with constant heat supply. We discussed how to improve the thermal environment with breeze-line type outlets in winter.

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Accurate pressure drop data on ventilation systems' components is requisite for design of ventilation system, which has to meet planed ventilation rate. However, existing measurement protocols for components of ventilation systems can not be applied to every kinds of component, judging from the review on the related technical papers, standards and regulations. Therefore in this paper, more precise measurement protocols are investigated with utilising a test chamber which has been generally used for existing protocols. The protocols are suggested for the measurement of duct and other ventilation systems' components. The measurement methods for components require the use of either "static pressure distribution method" or "duct's static pressure correction method". The former one is suggested as more accurate method and the latter one requires smaller test space with moderate measurement accuracy. Finally, measurement results on ventilation fan and ducts are shown as examples of the proposed methods.

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Indoor climate has a three-dimensional spatial distribution caused by three-dimensional airflow. To obtain the accurate knowledge of building performance, it is demanded to integrate the spatial distribution into building simulations. In these contexts, CFD analysis is necessarily in design process. However, at most only a few case of CFD could be executable in real design process, because of the large calculation cost. The main subject of this paper is the development of a method for extracting heat transport phenomena in rooms from such limited CFD analyses and integrating the data into a flow network model analysis. The calculation method is based on the fact that we can regard static flow field as a linear system, and the transient heat response on static flow field can be calculated through computation of convolution by using response factors. In this paper, we present the calculation steps: method obtaining heat response factor on flow filed; and method calculating transient heat response using those response factors, as well as examples of the simulation applied to air-conditioning control problems.

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The variable-speed chiller has variable speed control and capacity control function of a compressor to minimize the mechanical loss in all operating ranges. Thus, the variable-speed chiller has a high COP feature in accordance with the thermodynamic property. The COP characteristic of the variable-speed chiller is different with that of the fixed-speed chiller. So, it has been considered that the conventional operating method is not appropriate to design and operate the heat source system with variable-speed chiller for business use. There also have been few reports about the heat source system with the variable-speed chiller, which uses the urban unutilized heat source. This report describes the validity and energy reduction effect of the variable-speed chiller by comparison of the energy consumption, which is calculated by numeric simulation, in case of urban unutilized heat source method (groundwater, swage water, river water, sea water) and general cooling tower method as cooling heat source in a heat source system with the latest fixed-speed chiller and a heat source system with the latest variable-speed chiller. The urban unutilized heat source method with the variable-speed chiller is more effect to reduce energy consumption than the cooling tower method with the fixed-speed chiller. Especially, effect of groundwater use is remarkable and the energy consumption is reduced by 50%. Even when energy reduction is not expected by the urban unutilized heat source method with the conventional chiller, the urban unutilized heat source method with the variable-speed chiller shows the reduction of energy consumption. These noteworthy results indicate that the variable-speed chiller is more effective in using urban unutilized heat source than the fixed-speed chiller due to the extremely low mechanical loss and the high COP characteristic in the small temperature difference between the evaporating temperature (the chilled water leaving temperature) and the condensing temperature (the cooling water entering temperature). In addition, by comparison of year-round energy consumption, the urban unutilized heat source usage is effective in summer and middle season, especially high reduction effect by groundwater, and cooling tower usage is effective in winter season by low wet-valve temperature and proper cooling tower control. In other words, when there is the cooling load throughout the year, it is suggested to use the urban unutilized heat source system in summer and middle season and cooling tower system in winter season. Consequently, the combination of the latest variable-speed chiller and the urban unutilized heat source is equivalent or more effective than the combination of the latest inverter chiller and the cooling tower regardless type of the urban unutilized heat source.

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CFD code is used routinely to predict air movement and temperature distributions in indoor environment. Especially commercial CFD software is applied against complex geometry and multi-physics phenomenon. In this paper, we discuss the aspects related to numerical errors on choice of turbulence modeling and computational grid concerning the application of commercial CFD code. This paper consists of three examinations, comparison of (1) five different mesh designs, (2) different turbulence model, (3) different commercial CFD code. Finally, recommendations are given for execution of suitable CFD calculations.

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