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Article Citation - WoS: 20Citation - Scopus: 21Sensitivity Analysis of the Effect of Current Mood States on the Thermal Sensation in Educational Buildings(Wiley-hindawi, 2022) Ozbey, Mehmet Furkan; Ceter, Aydin Ege; Orfioglu, Sevval; Alkan, Nese; Turhan, CihanAdaptive thermal comfort is a model which considers behavioral and psychological adjustments apart from Fanger's Predicted Mean Vote (PMV)/Percentage of Dissatisfied (PPD) method. In the literature, the differences between the PMV/PPD method and adaptive thermal comfort were mainly considered in aspects of behavioral adjustments in an environment. Conversely, limited studies related to psychological adjustments were considered in detail for thermal comfort. This study purposes to investigate the effects of current mood state subscales on thermal sensation of the occupants for the first time in the literature. To this aim, the Profile of Mood States (POMS) questionnaire is used to determine the mood state of the occupants with six different subscales: Anger, Confusion, Vigor, Tension, Depression, and Fatigue. The experiments were conducted in a university study hall in Ankara, Turkey, which is in warm-summer Mediterranean climate (Csb) according to Koppen-Geiger Climate Classification. The distributions of each subscale were examined via Anderson Darling and Shapiro-Wilk tests accordingly given responses from the occupants. The sensitivity analysis was applied to the six subscales of the POMS with Monte Carlo simulation method by considering the distributions of each subscale. The results revealed that the current mood state has a crucial effect on the thermal sensation of the occupants. The subscales of the Depression and Vigor were found as the most vital ones among the six subscales. Only the pure effects of the Vigor and Depression would change the thermal sensation of the occupants 0.31 and 0.30, respectively. The Confusion was determined as the least effective subscale to the thermal sensation of the occupants. Moreover, with the combination of all the six subscales, the thermal sensation might change up to 1.32. Findings in this study would help researchers to develop the personalized thermal comfort systems.Article Citation - WoS: 34Citation - Scopus: 41Development of a Personalized Thermal Comfort Driven Controller for Hvac Systems(Pergamon-elsevier Science Ltd, 2021) Turhan, Cihan; Simani, Silvio; Akkurt, Gulden GokcenIncreasing thermal comfort and reducing energy consumption are two main objectives of advanced HVAC control systems. In this study, a thermal comfort driven control (PTC-DC) algorithm was developed to improve HVAC control systems with no need of retrofitting HVAC system components. A case building located in Izmir Institute of Technology Campus-Izmir-Turkey was selected to test the developed system. First, wireless sensors were installed to the building and a mobile application was developed to monitor/ collect temperature, relative humidity and thermal comfort data of an occupant. Then, the PTC-DC algorithm was developed to meet the highest occupant thermal comfort as well as saving energy. The prototypes of the controller were tested on the case building from July 3rd, 2017 to November 1st, 2018 and compared with a conventional PID controller. The results showed that the developed control algorithm and conventional controller satisfy neutral thermal comfort for 92 % and 6 % of total measurement days, respectively. From energy consumption point of view, the PTC-DC decreased energy consumption by 13.2 % compared to the conventional controller. Consequently, the PTC-DC differs from other works in the literature that the prototype of PTC-DC can be easily deployed in real environments. Moreover, the PTC-DC is low-cost and user-friendly. (c) 2021 Elsevier Ltd. All rights reserved.Article Citation - WoS: 13Citation - Scopus: 13Integration of Psychological Parameters Into a Thermal Sensation Prediction Model for Intelligent Control of the Hvac Systems(Elsevier Science Sa, 2023) Turhan, Cihan; Ozbey, Mehmet Furkan; Lotfi, Bahram; Akkurt, Gulden GokcenConventional thermal comfort models take physiological parameters into account on thermal comfort models. On the other hand, psychological behaviors are also proven as a vital parameter which affects the thermal sensation. In the literature, limited studies which combine both physiological and psychological parameters on the thermal sensation models are exist. To this aim, this study develops a novel Thermal Sensation Prediction Model (TSPM) in order to control the HVAC system by considering both parameters. A data-driven TSPM, which includes Fuzzy Logic (FL) model, is developed and coded using Phyton language by the authors. Two physiological parameters (Mean Radiant Temperature and External Temperature) and one psychological parameter (Emotional Intensity Score (EIS) including Vigour, Depression, Tension with total of 32 subscales) are selected as inputs of the model. Besides the physiological parameters which are decided intentionally considering a manual ventilated building property, the most influencing three sub- psychological parameters on thermal sensation are also selected in the study. While the physiological parameters are measured via environmental data loggers, the psychological parameters are collected simultaneously by the Profile of Mood States questionnaire. A total of 1159 students are participated to the questionnaire at a university study hall between 15th of August 2021 and 15th of September 2022. The results showed that the novel model predicted Thermal Sensation Vote (TSV) with an accuracy of 0.92 of R2. The output of this study may help to develop an integrated Heating Ventilating and Air Conditioning (HVAC) system with Artificial Intelligence - enabled Emulators that also includes psychological parameters.Article Citation - WoS: 15Citation - Scopus: 11The Relation Between Thermal Comfort and Human-Body Exergy Consumption in a Temperate Climate Zone(Elsevier Science Sa, 2019) Turhan, Cihan; Akkurt, Gulden GokcenHuman body exergy balance calculation method gives minimum human body exergy consumption rates at thermal neutrality (TSV = 0) providing more information on human thermal responses than other methods. The literature is lacking the verification of this method in various climatic zones. The aim of this study is to investigate the relationship between thermal comfort and human body exergy consumption in a temperate climate zone. A small office building in Izmir Institute of Technology campus, Izmir/Turkey, was chosen as a case building and equipped with measurement devices. The occupant was subjected to a survey via a mobile application to obtain his Thermal Sensation Votes. Objective data were collected via sensors and used for predicting occupant thermal comfort and for exergy balance calculations. Under given conditions, the results show that Thermal Sensation Votes are generally zero at a T-i range of 21-23 degrees C and, are mostly lower than Predicted Mean Votes in summer while the opposite is observed in winter. Predicted Mean Votes at minimum Human Body Exergy Consumption rates were on slightly warm side while Thermal Sensation Votes are zero. It means that for given case, the HBexC rate calculation gave a better prediction of the environmental parameters for the best thermal comfort. (C) 2019 Elsevier B.V. All rights reserved.Article Citation - WoS: 17Citation - Scopus: 18Effect of Pre-And Post-Exam Stress Levels on Thermal Sensation of Students(Elsevier Science Sa, 2021) Turhan, Cihan; Ozbey, Mehmet FurkanThe Predicted Mean Vote and Predicted Percentage of Dissatisfied (PMV/PPD) method is used worldwide to assess thermal comfort. The PMV/PPD method traditionally depends on four environmental parameters; air temperature, relative humidity, mean radiant temperature and air velocity, and two personal parameters; metabolic rate and clothing insulation. However, accurate modelling of thermal comfort requires consideration of psychological impacts, as well as associated physical responses to the environment. This paper investigates the effect of one of the psychological parameters; stress level on the thermal sensation of students for male and female which can be a sufficient limitation of the accuracy of thermal comfort/sensation models. Actual Thermal Sensation (ATS) and Profile of Mood States (POMS) are used to examine the effect of stress level on the thermal sensation. Pre-test-Post-test Control (PPC) experimental design is conducted on the students in a university, Ankara, Turkey, which has a Csb type climate zone according to Koppen-Geiger climate classification. First, students are split into two random groups; control and experimental groups. The students in experimental group are requested to attend exam while the students in control group read their favourite books. Then, students are subjected to pre-and post-exam surveys in order to understand the relationship between stress level and ATS. As a supportive analysis, Heart Rate (HR) and Skin Temperature (ST) are also included in the study as sympathetic responses of occupants to the thermal discomfort due to stress. Smart wristbands and infrared thermometers are used to measure Heart Rate and Skin Temperature of the students. Results showed that there is a difference between control group and experimental group before the exam (pre-test) except the ST of females. After the exam (post-test), there are no significant differences between two groups. (C) 2020 Elsevier B.V. All rights reserved.Article Citation - WoS: 16Citation - Scopus: 18A Comprehensive Comparison and Accuracy of Different Methods To Obtain Mean Radiant Temperature in Indoor Environment(Elsevier, 2022) Ozbey, Mehmet Furkan; Turhan, CihanThermal comfort is defined as "the state of mind which expresses satisfaction with the thermal environment" by the American Society of Heating, Refrigerating and Air Conditioning Engineers in the standard of the ASHRAE55. Thermal comfort is affected by six main parameters which are split into two categories; personal (basic clothing insulation value and metabolic rate) and environmental (air temperature, relative humidity, air velocity, and mean radiant temperature) parameters. The mean radiant temperature is a problematic parameter in thermal comfort studies due to its complexity. The mean radiant temperature approaches are based on different techniques such as calculation methods, measurement methods, and assumptions. Although the assumptions are utilized by researchers to abstain complexity, their accuracies are uncertain. To this aim, this study purposes to find the accuracies of calculation and assumption methods by comparing with reference measurement method. An office building in a temperate climate zone is selected as a case study. Two calculation methods and eight assumptions on obtaining mean radiant temperature are compared via in-situ measurements. The results revealed that using assumptions or calculation methods to obtain the mean radiant temperature caused a significant error compared to the reference method and researchers should consider accuracies of these methods before utilizing them in their applications.Article Citation - WoS: 21Citation - Scopus: 24Thermal Comfort Analysis of Historical Mosques. Case Study: the Ulu Mosque, Manisa, Turkey(Elsevier Science Sa, 2021) Diler, Yusuf; Turhan, Cihan; Arsan, Zeynep Durmus; Akkurt, Gulden GokcenMosques are sanctuary places for Muslims where they can perform their religious activities and also can communicate with each other. On the other hand, historical mosques may contain artworks which have cultural heritage values. These mosques originally have not any Heating, Ventilating and Air Conditioning systems. For this reason, obtaining thermal comfort becomes a significant issue. In this study, a systematic approach on monitoring and evaluating thermal comfort of historical mosques were developed. As a case study, The Ulu Mosque, Manisa/Turkey was monitored from 2015 to 2018, and thermal comfort evaluation of the mosque was conducted during prayer times based on the method provided by ISO 7730. A dynamic Building Energy Performance Software, DesignBuilder, was used to model the mosque, and the model was calibrated by using hourly indoor temperature data. The calibrated model was then used to evaluate existing conditions of the mosque and develop retrofitting scenarios in order to increase thermal comfort of prayers. Thirteen different scenarios were proposed to improve thermal comfort of prayers during worship periods. The results were evaluated according to EN 16883 for conservation of cultural heritage of the mosque. Electrical radiator heating with intermittent operating schedules was obtained as the best scenario to protect cultural heritage via artworks, while decreasing disssatisfaction level of the prayers from 45% to 10% in winter months. Additionally, intermittent operation saved 46.9% of energy compared to continuous operating schedule. (C) 2021 Elsevier B.V. All rights reserved.Article Citation - WoS: 3Citation - Scopus: 5Impact of Green Wall and Roof Applications on Energy Consumption and Thermal Comfort for Climate Resilient Buildings(Mdpi, 2025) Turhan, Cihan; Carpino, Cristina; Austin, Miguel Chen; Ozbey, Mehmet Furkan; Akkurt, Gulden GokcenNowadays, reducing energy consumption and obtaining thermal comfort are significant for making educational buildings more climate resilient, more sustainable, and more comfortable. To achieve these goals, a sustainable passive method is that of applying green walls and roofs that provide extra thermal insulation, evaporative cooling, a shadowing effect, and the blockage of wind on buildings. Therefore, the objective of this study is to evaluate the impact of green wall and roof applications on energy consumption and thermal comfort in an educational building. For this purpose, a university building in the Csb climate zone is selected and monitored during one year, as a case study. Then, the case building is modelled in a well-calibrated dynamic building energy simulation tool and twenty-one different plant species, which are mostly used for green walls and roofs, are applied to the envelope of the building in order to determine a reduction in energy consumption and an increase in thermal comfort. The Hedera canariensis gomera (an ivy species) plant is used for green walls due to its aesthetic appeal, versatility, and functional benefits while twenty-one different plants including Ophiopogon japonicus (Mando-Grass), Phyllanthus bourgeoisii (Waterfall Plant), and Phoenix roebelenii (Phoenix Palm) are simulated for the green roof applications. The results show that deploying Hedera canariensis gomera to the walls and Phyllanthus bourgeoisii to the roof could simultaneously reduce the energy consumption by 9.31% and increase thermal comfort by 23.55% in the case building. The authors acknowledge that this study is solely based on simulations due to the high cost of all scenarios, and there are inherent differences between simulated and real-world conditions. Therefore, the future work will be analysing scenarios in real life. Considering the limited studies on the effect of different plant species on energy performance and comfort, this study also contributes to sustainable building design strategies.Article Citation - WoS: 20Citation - Scopus: 23A Novel Comfort Temperature Determination Model Based on Psychology of the Participants for Educational Buildings in a Temperate Climate Zone(Elsevier, 2023) Ozbey, Mehmet Furkan; Turhan, CihanMaintaining thermal comfort in the educational buildings is vital due to the impacts on learning effectiveness of students. Therefore, development of a proper comfort temperature in educational buildings is a must. In naturally ventilated and mixed-mode buildings, the adaptive thermal comfort model, which considers additively psychological, and behavioural factors to the Fanger's PMV/PPD model, is commonly applied based on regression analyses. However, the psychological adjustments based on current mood state are very limited in these adaptive thermal comfort models. Therefore, this study focuses on the psychological adjustments in terms of Profile of Mood States in order to predict comfort temperature of students in a case building. The experiments are conducted in a university on a temperate climate zone for a long period-data including both heating and cooling seasons. In this study, the comfort temperatures for each student are determined via Griffith method for the case building. Moreover, the current mood states of students are assessed utilizing the Profile of Mood States survey, which are collected via a developed mobile application. As a conclusion, the relation between the current mood state of the students and comfort temperature are statistically investigated. The results show that a Griffith constant are found as 0.332/K and mean annual comfort temperature is found as 21.32 degrees C in the case building. Additionally, a significant difference is found in the comfort temperatures among the students who have more, or fewer concerns than typically reported. The novelty of the study is to present a comfort temperature determination model which considers human psychology as a starter study in the literature.Article Citation - WoS: 48Citation - Scopus: 52A Comprehensive Evaluation of the Most Suitable Hvac System for an Industrial Building by Using a Hybrid Building Energy Simulation and Multi Criteria Decision Making Framework(Elsevier, 2021) Bac, Ugur; Alaloosi, Khalid Abdulwahab Mohamed Saed; Turhan, CihanGreat demand for energy and growing trend in the use of energy-efficient HVAC systems force researchers to focus on the importance of choosing the most appropriate HVAC system for industrial buildings during design process. Therefore, developing a model to select the most suitable HVAC system is vital for industrial buildings. To this aim, this study provides a comprehensive evaluation of different HVAC systems for an industrial building by using hybrid multi criteria decision making (MCDM) method. An industrial building in Ankara/Turkey is selected as a case building. Eleven HVAC systems are evaluated based on twenty seven criteria, which are determined as a result of extensive literature research, and are grouped under six categories including ergonomic, environmental, reliability, technical, and economical aspects. A hybrid application of building energy simulation (BES) integrated modified Stepwise Weight Assessment Ratio Analysis (SWARA) and Weighted Additive Sum Product Assessment (WASPAS) framework is developed for supporting the decision making process. The novelty of the study is integrating the objective results of a well-calibrated dynamic BES tool with subjective criteria which are collected from expert opinions by applying questionnaires with face-to-face interview method. The results of MCDM framework and sensitivity analysis showed that the water-source heat pump is the best and suitable alternative for the industrial building. The outcome of this study would benefit the HVAC engineers and specialists in order to design the best HVAC systems in industrial buildings while providing an insight into different criteria. Moreover, key contribution to the literature is the usage of hybrid MCDM framework integrated with BES tool in the building sector.
