Vertical Air Temperature Difference Research Articles

Gender disparities in thermal responses under vertical air temperature differences

The effects of vertical temperature differences (VTD) on human thermal comfort have attracted growing attention from researchers when utilizing split air conditioners for winter heating. This study underscores the need to investigate the influences of gender disparities in the context of significant vertical temperature variations, a critical aspect that has not yet been comprehensively explored. Twenty gender-balanced subjects were exposed to a variety of stratified thermal environments created by a split air-conditioner. Their overall and local perceptual and physiological responses were measured at various operative temperatures and VTD. Results show that females have lower thermal sensation vote (TSV) and mean skin temperature under the same environments compared to males. Neutral operative temperatures of females and males are 23.7 ˚C and 20.8 ˚C, respectively. On the cold side, lower leg and foot thermal sensations are dominant whereas chest and back are dominant on the warm side. When females rated “slightly warm” (TSV equaled 1) or “warm” (TSV equaled 2), or males rated “slightly cool” (TSV equaled −1), increased VTD can lower thermal acceptability. The research findings have significant implications for the understanding of gender requirements of stratified heating environments and for maximizing the thermal comfort of the two genders.

Experimental Study of Indoor Air Distribution and Thermal Environment in a Ceiling Cooling Room with Mixing Ventilation, Underfloor Air Distribution and Stratum Ventilation

A ceiling cooling system integrated with a mechanical ventilation system has been widely used in modern buildings with large sensible cooling loads due to the high thermal comfort level and large energy efficiency. However, there is a lack of systematic research on the influence factors such as ceiling surface temperature and cooling load on the indoor air distribution and thermal environment, and the impact of ventilation system type in the ceiling cooling room is still unclear. Therefore, this paper presented an experimental study of indoor air distribution and thermal environment in a ceiling cooling (CC) room with mixing ventilation (MV), underfloor air distribution (UFAD) and stratum ventilation (SV); the ceiling surface temperature was 17 °C–26 °C and the internal or external cooling load was 41.5 W/m2–69.5 W/m2. The results showed that the vertical air temperature difference and contaminant removal effectiveness were 0.2 °C–0.4 °C and 0.53–0.85 with CC + MV, 0 °C–1.2 °C and 0.68–1.25 with CC + UFAD and 0.3 °C–0.9 °C and 0.50–0.83 with CC + SV, and the corresponding heat removal effectiveness and air diffusion performance index were 0.96–1.11 and 96–100%, 0.9–1.5 and 57–100% and 1.11–1.34 and 71–100%, respectively. Moreover, the difference between mean radiant temperature and air temperature and the predicted mean vote of thermal sensation were from 0 °C to 0.9 °C and between 0 and 0.26 with CC + MV, from −0.1 °C to 2.2 °C and between −0.1 and 0.42 with CC + UFAD and from −0.1 °C to 0.9 °C and between −0.2 and 0.13 with CC + SV. Hence, the ventilation system type clearly affected the indoor air distribution and thermal environment in the ceiling cooling room, and the experimental results would be beneficial for the design and control of a ceiling cooling system combined with a mechanical ventilation system in practice.

Evaluation of heating performances of different ventilation methods in an office

In this study, 12 cases were investigated in an office-layout room using experiments and computational fluid dynamics (CFD) simulations. The heating performances of four ventilation methods (i.e. mixing ventilation (MV), stratum ventilation (SV), deflection ventilation (DeV) and impinging jet ventilation (IJV)) were comprehensively compared by various evaluation indexes (i.e. predicted mean vote (PMV), draught rate (DR), vertical air temperature difference (△T), air diffusion performance index (ADPI), energy utilization coefficient (EUC), air change efficiency (ACE) and contaminant removal efficiency (CRE)). Better thermal comfort was found in rooms heated by SV and DeV. The PMV, DR and △T under SV and DeV complied with Category B of ISO 7730:2005, and the ADPI was in full compliance with the stipulation of ANSI/ASHRAE 113-2022. For the energy-saving characteristic, the targeted-occupied-zone ventilation methods (i.e. SV, DeV and IJV) can effectively deliver warm air to the occupied zone, with the EUC values higher than unity and thus providing a good potential for energy saving. SV and IJV showed slightly higher ACEs in the breathing zone. The contaminant removal effectiveness of SV, DeV and IJV was comparable. Under the combined influence of occupant thermal plumes and locations of exhausts, MV showed a high CRE. However, the CRE under MV decreased significantly when the exhausts were not above occupants. In the case of supply air parameters in this study, the entropy-weight method indicated that DeV and SV had a better overall performance for winter heating, followed by IJV and then MV.

Effect of thermal manikin shape on thermal comfort parameters prediction uncertainties: a numerical study

The main goal of the study is to evaluate the effect of the thermal manikin shape on the uncertainty of thermal comfort parameters CFD prediction. Numerical simulation of the airflow and heat transfer was carried out in a model room with displacement ventilation where a standing heated thermal manikin is located (test by P.V. Nielsen et al.). Numerical modelling was carried out using three manikin shapes: the detailed one (close to the human body shape), the simplified (block) one, and the single-parallelepiped shape. The 3D calculations were carried out using the ANSYS Fluent CFD package. Turbulence modelling was performed using the Reynolds-Averaged Navier-Stokes (RANS) approach with the standard k-ε turbulence model. The uncertainties in the CFD-predicted draught rating (DR), percentage dissatisfied caused by vertical air temperature difference (PD), the predicted mean vote (PMV) and the predicted percentage dissatisfied (PPD), are discussed. The main result of the paper is the quantitative evaluation of the changes in the local velocity, temperature and thermal comfort parameters due to the thermal manikin shape simplification. It was found that the shape simplifications are suitable if the goal of the study is to predict the integral parameters.

Local thermal comfort chart for non-uniform building environments: Comparison with vehicle environments and its application

There have been many laboratory studies of human subjects exposed to non-uniform thermal environments such as radiant temperature asymmetry from different directions, vertical air temperature differences, and draught. However, there are no final conclusions on the unified quantitative index for general non-uniform environments, which will be stressed in this study. The equivalent temperature (teq) that integrates air temperature, radiant temperature and air velocity at different body parts and well relates with thermal perceptions is adopted as an integral evaluation index. Published data from laboratory measurements of office environments with subjects exposed to different types of radiant asymmetry and measurements with a thermal manikin were analysed. A new comfort chart of teq was developed to evaluate non-uniform building environments and it was compared with the existing comfort chart (in ISO 14505) applied in vehicle. The results indicated that overall sensible heat loss of the human body remained constant, but local thermal discomfort and sensation changed with the non-uniform environments. The new comfort chart identified the source of discomfort and predicted the observed subjective evaluations. Significant discrepancy of the comfort chart between buildings and vehicles was found, indicating the necessity of developing a comfort chart that applied in the building environment. The study provides new insights into the causes of local thermal discomfort and can provide information on the sensitivity of different body parts to heat loss that can be used to optimise the thermal design of indoor environments.

Evaluation of thermal comfort in air-conditioned rooms based on structure/control-related parameters and data-mining method

Evaluating the thermal environment and thermal comfort in an air-conditioned room is an essential for estimating the performance of air-conditioning systems. However, multiple component structures and control-related parameters often lead to a long test cycle and large number of tests, significantly affecting the testing efficiency and speed. To address these problems, in this study, a data-mining method was proposed to predict and evaluate the thermal environment of an air-conditioned room. Owing to the limited amount of experimental data, the sample data were expanded by the simulation data of a collaborative platform between the air-conditioning system and air-conditioned room. Data-mining models, including the support vector regression (SVR), backpropagation (BP), and multiple linear regression (MLR) models, were developed and achieved good accuracy in evaluating the thermal environment by considering air-conditioning systems with various structures and control parameters. In the multiple-input single-output evaluation method, the prediction accuracy of the SVR model was higher than those of the BP and MLR models with respect to the vertical air temperature difference, temperature uniformity, temperature drop rate, and draft rate, while the result was the opposite in terms of the predicted mean vote indices. In the multiple-input multiple-output evaluation method, there was a decline in prediction accuracy and an increase in efficiency prediction compared with multiple-input single-output evaluation.

A Combinatorial Optimization Strategy for Performance Improvement of Stratum Ventilation Considering Outdoor Weather Changes and Metabolic Rate Differences: Energy Consumption and Sensitivity Analysis

Since occupants spend most of their time indoors, an energy-saving and comfortable indoor environment are particularly important. The differences in the metabolic rate of occupants make them have different requirements for their thermal environment. To save energy under the comprehensive needs of occupants for thermal environment, the combinatorial optimization strategy based on NSGA-II and improved the TOPSIS method is proposed in this study. Firstly, the physical model of the CFD simulation is verified by experiments. Secondly, the specific operation cases corresponding to combinations of different levels of factors are determined via the RSM method, and the ventilation performance prediction model considering the metabolic rate differences and outdoor weather changes is established. Thirdly, supply air velocities and temperatures are optimized by using Pareto-based NSGA-II; the Pareto optimal solution set under different outdoor temperatures is obtained. Finally, based on the Pareto optimal solutions at different outdoor temperatures, the optimal strategy under dynamic outdoor air temperature is obtained by improved TOPSIS by the CRITIC method. The optimization of ventilation parameters significantly improved the ventilation performance, and the results show that the predicted mean vote, energy consumption, vertical air temperature difference between head and ankle levels and the local mean age of air for different metabolic rates decrease by 64.1%, 4.74%, 24.83% and 7.39% on average, respectively. Moreover, the relative energy saving rate increases as the metabolic rate increases, and the strategy facilitates adaptation to outdoor weather changes and meets the individual needs of occupants for the indoor environment. This has important implications for achieving the global goal of energy efficiency and emission reduction.

Effects of vertical air temperature differences on thermal comfort, mental performance, and physiological responses: A review

Effects of vertical air temperature differences on thermal comfort, mental performance, and physiological responses: A review

An experimental comparison of radiant wall and ceiling cooling system integrated with ground source heat pump and direct expansion fan coil system in a highly glazed office room

Hydronic radiant systems, which provide a thermal comfort environment, come to the fore in different building applications due to their energy saving potential and being integrated with renewable energy systems. The aim of this study is to present a full-scale experiment to compare the thermal comfort performances of radiant ceiling, wall and wall + ceiling systems coupled ground source heat pump and direct expansion fan coil system implemented in Yildiz Technical University Science and Technology Application and Research Center, Istanbul, Turkey. Air velocity, horizontal and vertical air temperature differences, mean radiant temperature and humidity values, which are four physical parameters that can affect the thermal satisfaction of office workers for 9 different experimental conditions, are measured for fan coil and all radiant systems. The results indicate that vertical temperature differences between ankle and head level vary from 0.9 °C to 1.4 °C for both fan coil system and all radiant system configurations in different location of the test room. Acceptable overall comfort in indoor environments Class A only showed stable performance with an average of 0.12 PMV and 5.3 % PPD when ceiling + wall radiant panels were actively cooled. The result shows that the difference between room air temperature and room operating temperature varies between 0.45 °C and 0.6 °C when cooling loads are met by radiant systems. This may not make it possible to use indoor air temperature instead of indoor operating temperature in the control of radiant systems. Moreover, the thermal environment of the radiant system are more uniform than fan coil system due to low air temperature stratification, air velocity and small differences between mean radiant temperature and indoor air temperature.

Experimental investigation of thermal comfort performance of a radiant wall and ceiling panel system

The number of radiant heating-cooling systems in building applications is increasing it is because of low energy consumption, low operating temperature and high values they provide in terms of working compatibility with renewable energy sources. In this study, ground source heat pump integrated radiant panels installed on the wall and suspended ceiling of the office room in Yıldız Technical University Science and Technology Application and Research Centre were experimentally examined in terms of thermal comfort according to the relevant standards. Vertical air temperature differences and mean radiant temperatures were investigated. The mean air temperature differences at 0.1 m and 1.7 m were found to be 3,9 oC 2.9 oC 3.5 oC, 3.1 oC and 3.4 oC on average for the five different stands, respectively. PMV and PPD values were found to be 0.78 and 18.9% for February 12 (Case 1), 0.36 and 8.4% for February 13 (Case 2), respectively. In the experiment carried out under the conditions of Case 2, while the comfort conditions were provided in almost all of the day, the desired comfort conditions could not be achieved in Case 1 after 11 am.

Stratum-air-distributed radiant-convective room air conditioner for heating

The radiant-convective room air conditioner has been demonstrated to improve the coefficient of performance and the heating capacity effectively. However, the applicability of the radiant-convective room air conditioner in modulating the indoor thermal environment is unclear. This study proposes a stratum-air-distributed radiant-convective room air conditioner and evaluates its effectiveness for providing thermal comfort under heating mode with experimentally validated CFD simulations. Results show that the heat output of the radiant panel of the room air conditioner accounts for 20.7 %- 34.5 % of the total heat output. The supply airflow rate should be properly determined to balance the highly coupled heat output and air distribution. Compared with the conventional room air conditioner, the proposed room air conditioner under proper operation more effectively warms the occupied zone because of the enlarged heat output and improved air distribution, thereby increasing the predicted mean vote from −0.15 to −0.02, reducing the vertical air temperature difference from 6.7℃ to 0.8℃, and enhancing the thermal utilization effectiveness from −0.09 to 0.25. In addition, the draft rating and radiant temperature asymmetry of the proposed room air conditioner are thermally acceptable. Therefore, the proposed room air conditioner can modulate the indoor thermal environment energy-efficiently from the aspects of both overall and local thermal comfort.

Thermal sensation, sick building syndrome symptoms, and physiological responses of occupants in environments with vertical air temperature differences

Vertical air temperature differences (VTDs) can have important influences on thermal comfort and the evaluation of air distributions. The air distributions might create either positive or negative VTDs. However, no research has clearly revealed the effect of different directions of VTDs on human comfort. To create environments with positive and negative VTDs in this study, the air temperature of half of the body was maintained at an air temperature of 25 °C, whereas the other half of the body (the upper or lower body part, respectively) was exposed to air temperatures of 22 °C, 25 °C, 28 °C, and 31 °C, respectively. That is two series of experiments with the same VTD value but different directions were compared, based on 16 subjects seated in a climatic box in a climate chamber. The thermal sensations, sick building syndrome (SBS) symptoms, and physiological responses of occupants were studied. The results showed that subjects were more sensitive to the VTD at the upper body part in warm environments with respect to thermal sensations, perceived air quality, and sweat intensity. The analysis indicated that there were more discomfort and heat stress for positive VTDs than negative VTDs. Thus, the criterion for acceptable negative VTDs should be different with the positive VTDs incorporated in current standards. Overall, the directions of the VTDs were suggested to be considered for evaluating the thermally stratified air distributions based on both of thermal comfort and energy efficiency in buildings.

Thermal sensation and percentage of dissatisfied in thermal environments with positive and negative vertical air temperature differences

Considering the percentage of dissatisfied due to local thermal sensation (PDLTSV), a vertical air temperature difference (ΔTd) threshold of about 3 °C was recommended in standards. However, some novel air distribution methods might create large positive (which means the head warmer than the feet, vice versa) or negative ΔTd, with no suitable proved criteria to be used. In this study, sixteen subjects were seated in a climatic box placed in a climate chamber to evaluate thermal sensation and percentage of dissatisfied with negative and positive ΔTd in different whole-body thermal conditions. Air temperatures were controlled independently at the upper and lower body parts, with 13 different air temperature sets combined with 22 °C, 25 °C, 28 °C, and 31 °C (i.e. -9 °C ≤ ΔTd ≤ 9 °C). Results showed that subjects were more thermally sensitive at the upper body and with positive ΔTd than at the lower body or with negative ΔTd. The 80% acceptable ΔTd range is about -8 to 7 °C in overall neutral (TSV = 0), -7 °C to 6 °C in slightly cool (TSV = -0.5) conditions, which is wider than -3 to 3 °C in slightly warm conditions (TSV = +0.5). By considering the factors of both TSV and ΔTd, a new overall percentage of dissatisfied index (OPDP) was proposed. Case studies show that the new OPDP index is more precise and suitable for the evaluations of different air distributions to predict overall percentage of dissatisfied in thermal environments with vertical air temperature difference.

Experimental Study on Operating Characteristic of a Combined Radiant Floor and Fan Coil Cooling System in a High Humidity Environment

The combined radiant floor and fan coil cooling (RFCAFC) system is widely used due to its high comfort and large energy saving potential. In this study, as an example, the combined RFCAFC system was studied in a high humidity environment in Jinan, Shandong Province, China. The novelty of the combined RFCAFC system lies in its ability to automatically adjust the water supply temperature of the radiant floor and fan coil in real time according to outdoor meteorological conditions, achieving thermal comfort while eliminating the likelihood of condensation on the radiant floor surface. Days with similar outdoor meteorological conditions were grouped, and the comfort level and hourly cooling performance coefficient (EERh) of different operating strategies for different outdoor meteorological conditions were monitored along with other evaluation indicators. The RFCAFC had good energy efficiency and comfort in a high humidity room environment. This study showed that the indoor vertical air temperature difference ranged from 1.6 to 1.8 °C, which met the ASHRAE55-2017 standard. The radiant floor surface temperature uniformity coefficient (S) fluctuated between 0.7 and 1.0, and the time it took the radiant floor surface temperature to reach 63.2% of the total variability range (τ63) for different operation strategies based on different outdoor meteorological conditions ranged between 4.4 and 4.7 h, which was within the normal range. The proportion of the total cooling capacity contributed by fan coil cooling under low temperature and high humidity (LH), high temperature and low humidity (HL), and medium temperature and medium humidity (MM) were 68.0%, 73.8%, and 71.7%, respectively. Based on this study, the following recommendations for the combined cooling system can be made: (1) When the outdoor humidity is high, the radiant floor system should be turned on early to provide cooling capacity. When the outdoor temperature is high, the fan coil system should be turned on early to reduce the indoor temperature. (2) To reduce energy consumption and achieve efficient operation of the system, the radiant floor system should be continuously operated to maximize its contribution to the cooling capacity, while the fan coil can be operated intermittently. Natural cooling can be integrated to provide additional cooling capacity to the room in the hours preceding occupation (i.e., 7:00–9:00). (3) The operation strategy of the combined cooling system must be able to respond in real time to changes in outdoor meteorological conditions to prevent discomfort in times of extreme heat or humidity.

Investigation of Indoor Asymmetric Thermal Radiation in Tibet Plateau: Case Study of a Typical Office Building

The unique climate in cold plateaus leads to long and cold winters, which result in the characteristics and creation of an indoor thermal environment different from that of plain areas. However, there is a lack of detailed research on and evaluation of indoor temperature distributions. This study took an office building in Lhasa as an example to study the indoor non-uniform temperature distributions with radiator and solar radiation. The indoor and outdoor thermal environment parameters were tested. Next, a numerical model was established and verified. On a typical winter weather day, although the average indoor air temperature and radiation temperature in Lhasa are higher than those in Beijing (both are cold areas), the temperature in both is lower than comfortable levels. The indoor vertical air temperature differences are below 3 °C, with a 5% dissatisfaction most of the time. Solar radiation and radiators seriously affect the uniformity of the indoor thermal environment. The radiation asymmetry in Lhasa is significant, and the maximum radiation temperature asymmetry can reach 8.73 °C. In addition, the setting of north-facing windows should be avoided as far as possible in Tibetan areas. Suitable design and evaluation standards should pay attention to the obvious phenomenon of uneven indoor temperature distribution.

Comparison of Indoor Air Distribution in a Ceiling Cooling Room with Different Mechanical Ventilation Systems

This paper presents an experimental study concerning the influence of ventilation system type on indoor air distribution in a ceiling cooling (CC) room with mixing ventilation (MV), underfloor air distribution (UFAD) and stratum ventilation (SV) when the internal or external cooling load was increased from 41.5 W/m2to 69.5 W/m2. The distributions of indoor air temperature, air velocity and contaminant concentration were measured and evaluated by the vertical air temperature difference, turbulence intensity and contaminant removal effectiveness, respectively. The results show that when the ceiling surface temperature increased from 17.0°C to 26.0°C, the vertical air temperature differences, turbulence intensities and contaminant removal effectiveness were 0.2°C-0.4°C, 27%-34% and 0.53-0.85 with CC+MV, 0.2°C-1.2°C, 27%-43% and 0.68-1.25 with CC+UFAD and 0.3°C-0.9°C, 24%-40% and 0.5-0.83 with CC+SV. The CC+MV had the most uniform distributions of indoor air temperature and velocity, whereas the CC+UFAD had the most non-uniform distribution of indoor contaminant concentration.

Comparison of thermal comfort between radiant and convective systems using field test data from the Chinese Thermal Comfort Database

This paper compares indoor thermal environment and thermal comfort between radiant and convective systems in continuous operating mode using large field test samples from the Chinese Thermal Comfort Database. Hypothesis tests are performed to compare thermal environment parameters and human subjective responses. We are concerned not only with statistical significance (P-value), but also with the effect size (d), since a small size effect would not have any practical significance. There is evidence of overheating of radiant systems due to high air temperature during heating season. There is no practical difference in air temperature between the two systems during cooling season. Indexes of radiant temperature asymmetry, vertical air temperature difference, air velocity and floor surface temperature are analyzed and compared. There is little practical difference in thermal comfort vote between the two systems at the same PMV interval. The neutral temperature difference is within 1.1 °C during heating season and is within 0.3 °C during cooling season between the two systems, which are narrower than the GB50376-2012 (2 °C during heating season and 0.5–1.5 °C during cooling season). This paper can provide reference for thermal environment design and thermal comfort evaluation under different HVAC systems.

Thermal environment investigation of asymmetric radiation coupled with convection heating.

The couple of radiation with convection heating owned advantages of less energy utilization, healthier and more comfortable indoor environment. However, local thermal discomfort was often induced by large vertical temperature difference and radiation asymmetry temperature. This work studied indoor thermal environment characteristics under different coupling ways of radiation and convection heating terminals through experiments and CFD simulation. The studied five scenarios were denoted as: (I) lateral air supply + adjacent side wall radiation, (II) lateral air supply + opposite side wall radiation, (III) lateral air supply + floor radiation, (IV) lateral air supply + adjacent side wall radiation + floor radiation, and (V) lateral air supply + opposite side wall radiation + floor radiation. The overall thermal comfort indices (including air diffusion performance index (ADPI), predicted mean vote (PMV), and predicted percent of dissatisfaction (PPD)) and local thermal comfort indices under different scenarios were investigated. For Scenarios I–III, the local dissatisfaction rates caused by vertical air temperature difference were 0.4%, 0.1%, and 0.2%, respectively, which belonged to “A” class according to the ISO-7730 Standard. While the vertical asymmetric radiation temperature of Scenario I/II was about 6.5 °C lower than that of Scenario III/IV/V. The ADPI for Scenarios III–V were about respectively 5.7%, 16.7%, and 21.0% higher than that of Scenarios I–II, indicating that a large radiation area and radiation angle coefficient could reduce the discomfort caused by radiant temperature asymmetry. The coupling mode improved local discomfort by decreasing vertical temperature difference and radiation asymmetry temperature wherefore improving the PMV from −1.6 to −1. The lateral air supply coupled with asymmetric radiation heating could potentially improve the thermal comfort of occupied area, while the comprehensive effect of thermal environmental improvement, energy-saving, and cost-effectiveness needes to be further investigated.

Prediction and Evaluation of Dynamic Variations of the Thermal Environment in an Air-Conditioned Room Using Collaborative Simulation Method

In this study, a collaborative simulation method is proposed to predict dynamic variations of the thermal environment in an air-conditioned room. The room thermal environment was predicted and analyzed by varying the structural and control parameters of the air conditioner considering the dynamic coupling effect. Connections and regularities were established between the applicable parameters and evaluation indices of the thermal environment. The simulation results demonstrated the interactions among the system structural parameters, control parameters, and the thermal environment. Within a certain parameter range, the evaporator structure exhibited a significant effect on temperature uniformity and vertical air temperature difference, followed by predicted mean vote (PMV) and draught rate (DR). The associated evaluation indices were sensitive to fin spacing, tube spacing, and tube outer diameter, in the same order, which were structural parameters of the evaporator. The effect of the air supply angle on the vertical air temperature difference was evident; however, its influence on the PMV, DR, and temperature uniformity did not indicate consistent variations.

Experimental study on the thermal comfort in the room equipped with a radiant floor heating system exposed to direct solar radiation

In buildings with highly glazed facades, the main drawback of radiant floors is the overheating problem when exposed to direct solar radiation. Combined with local climate data from Troyes, an experimental investigation was performed under various exposure duration 2, 4, and 6 h with different solar intensity scenarios that were experimentally realized by a heating film. Indoor air temperatures and floor surface temperature were measured. Obtained results showed that the maximum floor surface temperatures all exceeded the limitation of 29 °C during the sunshine durations. When the sun patch was applied on the floor, the building type changed from category A to category B in terms of the vertical air temperature difference. To sum up, the sun patch indeed gave rise to floor overheating problems in the case of the existing control system, and the case of 6h sunshine duration with an intensity of 718 W/m2 would lead to the worst living conditions taking all factors consideration. The findings and insights of this study will provide an experimental database for designers and engineers.