bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlled inlet airflow in ventilated facades: a numerical analysis
Authors: Pergolini M , Ulpiani G , Shehi O , Di Perna C , Stazi F 
Published: October 2019

Abstract
A research study was conducted to investigate the summer thermal performance of different ventilated façades, by means of experimentally validated numerical simulation. Three ventilated configurations were tested: L, with a lightweight external layer, IM and EM with a massive cladding respectively in the inner and outer side of the air cavity. TRNSYS was used to simulate the thermal behaviour of the façades. Five increasing air speeds were imposed at the inlet (from 0.2m/s to 2m/s). Air temperature and heat flux trends, at different wall positions, were surveyed. The experimentation was carried out on a lightweight and hyper-insulated mock-up in Central Italy. The airflow rate at the inlet was controlled by means of pulse width modulation (PWM) controlled axial fans installed on top of the air gaps. Temperature, air velocity, and thermal flux measurements were collected to validate the model. Simulation results were later post-processed by means of linear regression analysis. As expected, as the airflow speed increased, the air temperature within the cavity gradually and asymptotically decreased. With air speeds above 1.6 m/s, the cavity temperatures in the massive configurations EM and IM settled at around the same value. Further investigation regarded the comparison of the heat flux profiles. The EM prototype was found to outperform the others since it more effectively prevented the heat from entering the test room and allowed a significant heat share to be released, too.
Optimal Night Mechanical Ventilation control strategy in office buildings
Authors: Guo Rui , Hu Yue , Liu Mingzhe , Heiselberg Per 
Published: October 2019

Abstract
Overheating in buildings during summertime, especially in office buildings is emerging as a challenge. Night mechanical ventilation (NMV) seems to be an energy-efficient technique by inducing the cold ambient air with a fan to cool the exposed building thermal mass and save air-conditioner energy for the following day. However, as sufficient cooling energy should be stored in thermal mass at night, the minimum indoor air temperature setpoint is relatively low, which may cause an overcooling penalty. Moreover, the NMV energy consumption may outweigh the energy saved for the air-conditioner at next daytime. Therefore, a multi-objective optimization was conducted to explore the optimal NMV control strategy to improve the building energy performance and indoor thermal comfort concurrently, based on a typical office building with three thermal mass levels in three climate regions. The final optimal NMV control strategies under different scenarios are presented in this study. The results show that the total cooling energy consumption of the final optimal NMV control strategies reduces 0%-8.6%, while the Predicted Percentage of Dissatisfied (PPD) during occupied hours decreases 0%-59.4%, compared to the base NMV control strategy in different scenarios. The benefit of the night cooling control strategy optimization is obvious in cold and medium climate region.
Sensitivity analysis of control strategies for mechanical ventilation in a low-energy apartment building
Authors: Kolarik Jakub , Bojsen Johan , Larsen Mathias J , Zukowska Daria 
Published: October 2019

Abstract
Building simulation tools are increasingly used during design of new as well as refurbishment of residential buildings. However, reliability of simulation is highly dependent on its inputs. The project investigated application of sensitivity analysis on input parameters for simulation of ten different residential ventilation control strategies. Nine strategies comprised demand control (DCV) one used constant air volume. Demand was represented by operative temperature, CO2, relative humidity or their combinations. They were measured either in ventilation exhaust or in particular rooms. Primary energy consumption and quality of indoor environment were evaluated. A low-energy apartment of 93.8 m2 placed in Nordhavn, Copenhagen, Denmark was used as a case study. Investigated input parameters were: heating set-point, occupancy schedule, window opening, internal heat and moisture gains, glazing area, g-value, solar shading and night ventilation. The control strategy capable of providing the best indoor climate (DCV with combination of sensors in individual rooms) was at the same time the most energy demanding. The sensitivity analysis revealed that heating setpoint and window opening were the most crucial input parameters with respect to primary energy consumption. Window opening was also the most influential factor with respect to overheating and moisture. Occupancy had a strongest effect on CO2.
Performance of mechanical filters used in general ventilation against nanoparticles
Authors: Brochot C , Bahloul A , Abdolghader P , Haghighat F 
Published: October 2019

Abstract
Filtration is a simple and effective way to capture particles of different sizes. According to ANSI/ASHRAE 52.2 standard, ventilation filters efficiency is tested for particles ranging from 0.3 to 10.0 μm. To our knowledge, performances of entire filters for nanoparticles are still very limited and particle size of 300 nm is commonly used as the Most Particle Penetration Size (for mechanical media). In order to evaluate the filter performance for nanoparticles, five type of filters (from MERV 8 to HEPA) were evaluated via two measurements: penetration and pressure drop. Results are consistent with previous experimental measurements on media and entire filters. These data show that the range of 150 to 500 nm is a better estimation of the MPPS, unlike the fixed diameter of 300 nm.
The investigation of indoor air quality and ventilation of an airport terminal building in China
Authors: Hong Jiajie , Lin Borong 
Published: October 2019

Abstract
This study aims to explore the actual indoor air quality and ventilation of an airport terminal building in Hot-Summer-Cold-Winter (HSCW) zone of China, based on long-term monitoring data of CO2 concentration, which were measured with 50 environmental sensors from September, 2017 to April, 2018.The key findings of this study can be summarized as follows: 1) The median values of CO2 concentration were lower than 550 ppm in all areas including check-in area, security check area, departure lounge with air bridges, arrival lounge, baggage claim area except the remote departure lounge; 2) Subjective questionnaire survey found that passengers were very satisfied with indoor air quality;3)The air contained in the large indoor space and the large amount of outdoor infiltrated air played an important role in the dilution of indoor pollutants; 4) Fresh air experiment showed that IAQ in the terminal building didn’t worsen without the supply of fresh air; 5)The number of air changes was calculated by the carbon dioxide attenuation method, and it was found that The arrival floor where gates are normally open and connected to the traffic center has large amount of air exchange. Building energy simulation results revealed that 24% heat was lost in winter through fresh air heating and 57% through air infiltration. In addition, the suggestions for ventilation improvements were also proposed.
The assessment of natural ventilation performance for thermal comfort in educational space: a case study of design studio in the AAST-Alexandria
Authors: Sarhan A , Abd El Gelil R , Awad H 
Published: October 2019

Abstract
Through the last decades, the impact of thermal comfort on the working performance of users and occupants of an indoor space has been a concern. Research papers concluded that natural ventilation quality directly impacts the levels of thermal comfort. Natural ventilation must be put into account during the design process in order to improve the inhabitant’s efficiency and productivity. One example of daily long-term occupancy spaces is educational facilities. Many individuals spend long time receiving a considerable amount of knowledge and it takes additional time to apply this knowledge thus, this research is concerned with user’s level of thermal comfort in design studios of educational facilities. The natural ventilation quality in spaces is affected by a number of parameters including orientation, opening design and many other factors. This research aims to investigate the conscious manipulation of space physical parameters and its impact on natural ventilation performance which subsequently affects thermal comfort of users. The current research uses inductive methods to define natural ventilation design considerations, which are used in a field study in a studio in the university building in Alexandria (AAST) to evaluate natural ventilation performance through analysing and comparing the current case to the developed framework. Also, the study conducts a computational fluid dynamics simulation. Results have proved that natural ventilation performance is successful by only 50% from the natural ventilation design framework, these results are supported by CFD simulation.
The challenges of designing a NRVU-BVU for energy efficiency and enhanced IAQ
Authors: Cross A 
Published: October 2019

Abstract
Directive 2009/125/EC establishes a framework for the setting of Ecodesign requirements for energy- using products. ‘Many products have a significant potential for being improved in order to reduce environmental impacts and to achieve energy savings through better design which also leads to economic savings for businesses and end-users’ [1]. Commission Regulation (EU) No 1253/2014, also known as Ecodesign directive 1253/2014/EC, applies to ventilation units and establishes ecodesign requirements for placing on the market or putting into service. The ecodesign requirements should be introduced gradually in order to provide a sufficient timeframe for manufacturers to re-design products subject to said regulation. This discussion paper highlights the practical challenges of designing a compliant non-residential bidirectional ventilation unit (NRVU-BVU) with the aim of improving energy efficiency whilst enhancing indoor air quality and discusses potential options to meet or exceed the requirements.
Experimental study of thermal characteristics for a novel ventilation roof with composite phase change material (VRCPCM)
Authors: Kong Xiangfei , Li Xiaofei , Qiao Xu , Chang Yufan , Chen Wanhe 
Published: October 2019

Abstract
A phase change material particle (PCMP) was prepared by vacuum adsorption method, with the binary eutectic mixture of myristic acid and tetradecanol as phase change material (PCM) and expanded vermiculite (EVMT) as porous adsorption materials. Then PCMPs were pressed into composite phase change plates (CPCP) for the outside layer of roof to store the heat passively. The active cooling storage was provided by the cold water in the seamless steel pipe and the iron box containing binary eutectic mixture of lauric acid and tetradecanol on the indoor side. Combined with the ventilation roof, a novel ventilation roof with composite phase change material experimental hut was constructed. The cold storage performance test was conducted under the two strategies which were regularly opened ventilation layer at certain time and timing cooling while regularly opened ventilation layer. The first strategy result showed that CPCP effectively reduced the temperature of the outer surface of the roof and the ventilation layer was turned on at night, which could effectively reduce the indoor air peak temperature. The second strategy result under the active cooling condition showed that the indoor PCM could absorb the heat of the indoor air and reduce the indoor temperature and the indoor temperature fluctuation range.
Study on energy loss through door open while air conditioner running in commercial store
Authors: Lee Sihwan 
Published: October 2019

Abstract
While air conditioner is running, leaving doors and windows open is a great way to reduce operating efficiency and undermine the air conditioning system’s ability to bring the indoor to a comfortable temperature. However, merchants want to business with open the door to attract more customers and to increase sales. The purpose of this study is to evaluate the heat loss and thermal environment through the door open while air conditioner running. To achieve this goal, using full-scale measurement with the commercial store during the cooling period, the infiltration rate, thermal environment and energy consumption of air conditioner with door opened and door closed state were measured. The measured results show that the infiltration rate at the door opened state was increased by about 21.3 times compared to the door closed state. When the set temperature of the air conditioner was 24 °C, the room temperature with open the door was measured to be about 5 °C higher than the cases of close the door. However, the energy consumption was measured approximately 12 kWh/day and there was not difference with door state. This means that the energy consumption is not increased if the indoor air temperature would not reach the set point temperature of air conditioner.
An analysis of the ventilation rates in residential buildings
Authors: Yoo Jihyun , Lee Seungrim , Park Junseok 
Published: October 2019

Abstract
The ultimate goal of environmental buildings is to minimize the use of fossil fuels and resources while providing a comfortable environment for occupants. Through continuous research and development, the physical performance of the buildings has been greatly improved for this purpose. However, focusing only on physical performance, it is seen that there is a big discrepancy between predicted and actual performance of building by treating occupants, who are the most affective object of building and energy consumption, as simple passive elements. These results increase the energy and cost of the building and become an obstacle to the construction of environmentally friendly buildings. Among occupant behavior, window opening is the biggest factor of increasing heating and cooling energy consumption. The purpose of this paper is to analyze the ventilation rate of each window opening for being embedded in an energy simulation program. A method to analyze the ventilation rate was carbon dioxide decay method as shown in Fig. 1. As a result, the ventilation rate was affected by the wind direction and speed, and floor level, but was somewhat constant because of monsoon effect in summer and winter of Korea.
Measuring and identifying background noises in offices during work hours
Authors: Rossi E , De Salvio D , D’Orazio D , Garai M 
Published: October 2019

Abstract
In offices and working places, noise analysis aims at enhancing the acoustic comfort, the concentration and the oral communication quality. According to the current regulations, background noise is evaluated in unoccupied conditions, but it is interesting to know its dynamic behaviour in occupied state. The knowledge of the noise components may be useful for improving the estimation of comfort parameters, such as the distraction distance (ISO 3382-3) or Speech Transmission Index (IEC 60268-16). The present study suggests a method to extract background noises values with statistical techniques from recordings made during work hours with sound level meters. Statistical techniques were used for the analysis of short-time sound pressure levels obtained over long-term recordings: Gaussian Mixture and Percentile Levels. Noise sources are identified from octave bands analyses. Measurements done using Gaussian Mixture were compared with the ones done with Percentile Levels. Results show some differences between the two techniques.
Numerical simulation the effect of natural ventilation on Indoor Environment Quality in the inner-corridor-type student dormitory in winter
Authors: Li Zhuangzhuang , Li Kaiyue , Chang Jin , Wu Huazhen , Liu Jiying 
Published: October 2019

AbstractPoor air quality in the dormitory will affect students’ physical and mental health and reduce their learning efficiency. The environmental status of university dormitory is gaining more and more attention. The indoor environment quality is always affected by outdoor condition during the heating period due to the requirement of natural ventilation. Using ANSYS Fluent software establishes a full-scale indoor and outdoor inner-corridor-type dormitory taking into account the different floor numbers. The results revealed that the living area on the south side of the corridor has a higher temperature and carbon dioxide concentration compared with the north side of the corridor. The balcony and corridor play an important role in maintaining the temperature of the dormitory. The mean velocity on the first floor is the lowest, and there is no significant difference in the air velocity in the living area on both sides of the corridor. The living area on the fifth floor has the better ventilation effectiveness. The results of this study will help architects understand the impact of natural ventilation on the indoor environment in inner-corridor-type dormitory.
Effect of air – exhaust location on surgical site particle distribution in an operating room
Authors: Agirman A , Cetin Y E , Avci M , Aydin O 
Published: October 2019

Abstract
This study investigates the effect of exhaust outlet location on airflow and particle distribution in an operating room with laminar ventilation system via computational fluid dynamics (CFD). Four different exhaust opening locations and three different particle diameters (5, 10 and 20μm) are taken into consideration for the same air change rate (30 ACH). It is found that the total number of particles deposited on the operating table decreased by 64 % for the smallest particle diameter (5 μm) and 26 % for the largest particle diameter (20 μm) when ceiling and floor level outlets are used together.
Novel methodology for diagnosis of causes associated with mould growth in dwellings
Authors: Lopez-Arce P , Altamirano-Medina H , Berry J , Rovas D , Sarce F , Hodgson S 
Published: October 2019

AbstractIncreased occupancy rates, inappropriate ventilation and intermittent heating regimes in dwellings can result in excessive atmospheric moisture levels, potentially leading to mould growth and lower indoor air quality. Identifying the causes associated to mould growth and taking correct remedial actions can be essential in reducing the prevalence of this problem. In practice it is often complex, even for experts, to accurately identify some of these causes and this can lead to costly and unnecessary interventions. Towards development of a novel systematic diagnostic procedure an extensive monitoring exercise has been undertaken involving collection of environmental data from dwellings with and without mould issues. The data has been analysed, considering building characteristics and occupancy’s lifestyle features, with the objective to identify thresholds on measurable parameters that are indicative of mould growth risks. The proposed methodology links key parameters to identify factors that contribute to surface condensation and mould growth in buildings. This research presents a process towards environmental data collection, post-processing to compute and interpret pertinent environmental parameters, and displaying them in a clear and easy-to-interpret manner.
Sensitivity analysis of envelope design on the summer thermal comfort of naturally ventilated classrooms in Taiwan
Authors: Chen Y H , Hwang R L , Huang K T 
Published: October 2019

Abstract
This paper uses Monte Carlo Analysis (MCA) for sensitivity analysis of the influence of sunlight shading and ventilation performance of classrooms in Taiwan on students’ cumulative overheating risk and average learning efficiency. The parameters influencing the sunlight shading and ventilation performance of classrooms include window orientation, window opening rate, ventilation rate, and external shading depth. EnergyPlus and local TMY3 weather data are used to simulate the hourly thermal environment conditions of 400 sample classrooms in two climatic regions (Taipei and Kaohsiung). The sensitivity of design parameters to the thermal risk of naturally ventilated classrooms and students’ learning efficiency is judged by using standardized regression coefficient, and the order of importance is window opening rate, ventilation rate, orientation, and external shading depth.
IoT network-based ANN for ventilation pattern prediction and actuation to optimize IAQ in educational spaces
Authors: Tagliabue L C , Re Cecconi F , Rinadi S , Ciribini A L C 
Published: October 2019

Abstract
Nowadays, in a user centered design approach, one of the main parameters for assessing the well-being of building spaces is Indoor Air Quality (IAQ), which can assure a crucial level of comfort and optimal conditions to preserve users’ productivity and cognitive performance. Research works in this direction mention that with 1000 ppm of CO2 concentration, a reduction of the users’ cognitive performance about 11-23% is reported and, for a concentration of 2500 ppm, the decrease reaches 44-94% compared to the performance at 600 ppm. Consequently, a correct buildings ventilation is crucial. The use of mechanical systems seems possibly to avoid the problem but indeed the existing buildings often have outdated and not flexible systems to face changing needs. Thereby, the ventilation rates are not related to people density and the static setup of HVAC systems might be an issue to maintain an acceptable level of CO2 concentration. Moreover, in school buildings, mechanical ventilation is not diffusely adopted and insufficient rates of fresh air supplied to the classrooms are connected with inappropriate IAQ, occurrence of SBS symptoms among pupils. Current technology provides easy measurement of CO2 through dedicated sensors networks. The present research uses the pilot educational building eLUX, located in the Smart Campus of the University of Brescia, to investigate the possibility to integrate IAQ data generated by IoT sensors to improve the estimation of occupancy rate in the educational spaces. The aim is to underline the relevance of the parameter to regulate properly the HVAC systems and to define opening/closing patterns for automated windows to enhance IAQ. The data collected during the monitoring phase are useful to train an Artificial Neural Network (ANN) that through an IoT communication protocol could actuate the ventilation rate control.
Simulation analysis of Macro-Packed Phase Change Materials (MPPCM) to reduce building energy use
Authors: Yeol Yun Beom , Yang Sungwoong , Hun Park Ji , Lee Jongki , Wi Seunghwan , Kim Sumin 
Published: October 2019

Abstract
This study sets up a zone-construction combination by constructing walls based on the classification of climates classified according to Korea’s energy saving design standards and the heat paring rate standard of the wall. There are four climatic divisions, C1, C2, S, and J, and we have used representative climate data for each climate. The target building was a residential apartment, which is the main residential type of large cities in Korea and the world. In the set combination, PCM of TES system is placed indoors, and applied PCM is n-hexadecane, n-heptadecane, n-octadecane with phase change temperature of 20-28 °C corresponding to room temperature standard. Each PCM is set at 0.1% to 0.9% of the area of the building. We used Energy Plus 8.7, a building energy simulation, and analyzed the energy saving and economic efficiency of the building. Saved energy was 2.71% on average and we were able to save up to 4.56%. In addition, we conducted an economic analysis, saving an average of 3.42% and saving up to 7.48%.