Characteristics of Indoor Thermal Environment in Office Building integrated with Thermally Activated Building System and HVAC System

2018 ◽  
Vol 12 (4) ◽  
Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 860
Author(s):  
Piotr Michalak

Modern buildings with new heating, ventilation and air conditioning (HVAC) systems offer possibility to fit parameters of the indoor environment to the occupants’ requirements. The present paper describes the results of measurements performed in an office room in the first Polish passive commercial office building during four months of normal operation. They were used to calculate parameters describing thermal comfort: vertical air temperature profile, floor surface temperature, predicted mean vote (PMV) and predicted percent of dissatisfied (PPD). Obtained results confirmed good thermal conditions in the analysed room. The average temperature of the floor’s surface varied from 20.6 °C to 26.2 °C. The average vertical air temperature, calculated for working days, was from 22.5 °C to 23.1 °C. The temperature difference between the floor and 5 cm below the ceiling was from −0.9 °C to 6.3 °C. The PMV index varied from 0.52 to 1.50 indicating ‘slightly warm’ sensation, in spite of ‘neutral’ reported by employees. Also measured cooling and heating energy consumption was presented. The performed measurements confirmed the ability of thermally activated building system (TABS) to keep good thermal conditions.


2019 ◽  
Vol 111 ◽  
pp. 01085
Author(s):  
Hiroshi Muramatsu ◽  
Tatsuo Nobe

In this study, an office building in Japan that incorporates energy-saving features and environmental technologies was investigated. This office building features a green façade, natural ventilation, a concrete slab with no suspended ceilings, and thermo-active building systems. Two airconditioning systems were installed in this building—a ceiling radiation air-conditioning system and a whole floor-blow off air conditioning system. In addition, a natural ventilation system was installed. We surveyed the heat flux of the ceiling surface and indoor thermal environment of this building from 2015 through 2016. The ceiling using the heat storage amount of concrete maintains a constant temperature in the workplace during as well as after office hours. We also performed detailed measurements of the heat flux of the ceiling surface and indoor thermal environment in the summer of 2017. The results showed that the ceiling radiation air-conditioning system provided a stable thermal environment. Furthermore, we report that making use of the thermal behavior of the skeleton improved the operation of the ceiling radiation airconditioning system.


2014 ◽  
Vol 556-562 ◽  
pp. 803-806
Author(s):  
Ze Qin Liu ◽  
Zhen Jun Zuo ◽  
Tai Shun Liu

A typical office building with stratum ventilation as the research object was studied in this paper. CFX Fluid Computation software was used to numerical simulate the characteristics of indoor thermal environment effected by air speeds under 19°C supply air temperature and 8 ventilation rate. The numerical simulate results showed that, the obvious thermal stratification occurred in the vertical direction. Such thermal stratification met the demands of building energy conservation and the human thermal comfort. In this paper, the velocity coefficient and the temperature coefficient were used to evaluate thermal comfort. From the results of the numerical simulation, it could be seen that when the supply air speeds were controlled between 0.5m/s to 0.9m/s, the thermal comfort, as well as the air supply efficiency in the human activity area was relative satisfactory. With the constant fresh air ventilated to the breathing zone, the air quality could be improved.


2014 ◽  
Vol 564 ◽  
pp. 228-233 ◽  
Author(s):  
Qi Jie Kwong ◽  
Mohamad Afri Arsad ◽  
Nor Mariah Adam

This paper presents the findings of a thermal comfort survey conducted in a tropical green office building. The building was installed with a slab-integrated radiant cooling system, which operated concurrently with an integrated variable-air-volume system. Evaluation of indoor thermal environment was made, where both objective and subjective assessments were carried out. The air temperature, air velocity, relative humidity and surface temperatures were measured by using calibrated sensors. Based on the data collected from the field assessment, the thermal comforts indices with expectancy factor were calculated. The results showed that thermal comfort parameters were within the comfort range specified in a local guideline, except for the air velocity profile. Besides, discrepancy between the Predicted Mean Vote (PMV) with expectancy factor and Actual Mean Vote (AMV) was found, which showed that the former still overestimated the thermal sensation of occupants although an expectancy factor of 0.5 was used.


Sign in / Sign up

Export Citation Format

Share Document