Teruyuki Saito

The effects of hypobaric conditions on man's thermal responses

Abstract Hypobaric conditions, with pressures about 30% below that at sea level, are often experienced at mountain resorts. The diffusive transfer of water evaporation increases at hypobaric conditions whereas dry heat loss by convection decreases. Two experiments were conducted to clarify the interactive effects between barometric and thermal events on mans thermal comfort. The experiments were conducted in a decompression chamber where the temperature was controllable. The temperature conditions were set at a constant 26°C or 30°C with 50% RH and 0.1 m/s airflow. The barometric conditions were examined stepwise for 1000, 2000, 3000 and 4000 m of simulated altitudes, which were held for 20 min at 26°C and 40 min at 30°C, respectively. Three male adults, lightly clothed, participated in each experiment. They remained sedentary for about four hours in the chamber. Thermal sensations were measured at each altitude with SD-rating scales. Subjects were also required to complete an introspection. The main results are as follows: when the altitude rose, (1) the heart rate increased for both temperature conditions: the increment at 26°C seemed to be based on hypoxia; (2) the skin temperatures of face and trunk were higher than those of extremities for both experiments; (3) thermal sensations for the face and trunk became warmer for both experiments, so subjects found it difficult to express their thermal state. Therefore, it is supposed that the blood flow in the body would change to compensate for hypoxia under hypobaric conditions.

A New Concept for Air-Conditioning in Japan: An All-Air Supplied Induction Radiant Air-Conditioning System and Cool Room

In recent years, all-air supplied induction radiant and laminar flow air-conditioning systems have been developed in Japan and are increasingly adopted. This chapter provides an overview of these air-conditioning systems, their performance in terms of energy savings as well as the results of subjective experiments regarding thermal comfort. Furthermore, the concept of a ‘cool room’ is explained as a way to improving thermal comfort when passing from the exterior to the interior of a building in the summer months. The results of subjective experiments on the effect of such a cool room are discussed as well as guidelines for their design.

RESEARCH ABOUT INTER ROOM FAN VENTILATION SYSTEM

We developed inter room fan ventilation system which transports indoor air mutually by small fan installed in the inner wall between rooms, and which is controlled according to the differences of specific enthalpy and CO2 concentration. The object of this study is to verify the improvement of indoor thermal environment by the application of this system. We installed this system into the model house and carried out the field study about temperature, humidity, and energy consumption etc. for nine months in 2005. The results are the following; 1) The ventilation route tend to be formed from LDK toward other rooms although it varied due to the seasons and the use of heating and cooling; 2) It was estimated that this system carried about 1-4 % of heating and cooling energy by transporting air between rooms; 3) We estimated temperature and humidity in non-heated room rose about 2-3°C and 0.6-1.2kg/kgDA by transporting air from heated room in winter.