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Evaluating the cooling effects of greening for improving the outdoor thermal environment at an institutional campus in the summer

May 7, 2013, 5:40 pm
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Publication date: Available online 7 May 2013
Source:Building and Environment
Author(s): Manat Srivanit , Kazunori Hokao
The thermal environment can have several effects on people who use outdoor spaces; especially on university campuses were the thermal environments of educational living spaces are important. This study focuses on the importance of greening as a potential method for passive cooling and for use in reducing ambient air temperatures, especially at a pedestrian level. There are two main strategies of greening modification. These two strategies have been proposed to improve campus environments and aim to include more greening area by adding trees to current green areas and by growing a grass layer on the rooftop of educational buildings. In this study, two approaches are presented, including an on-site measurement and a numerical simulation model that uses ENVI-met. These greening modification methods were investigated regarding their local cooling effect. This study was conducted at the institutional campus of Saga University, Japan. We hypothesized that the average maximum temperature would decrease and reach 2.27°C in the peak of the summer (at 15:00) when the quantity of trees was increased by 20%. Furthermore, combining both modification methods led to the largest air temperature decrease with an average and maximum of 0.24°C and 2.29°C, respectively. The results of this study allow university decision makers and planners to identify more precise green campus policies, which are necessary for improving the educational environment.

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Wetlands are an Effective Green Roof System

May 7, 2013, 5:40 pm
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Publication date: Available online 7 May 2013
Source:Building and Environment
Author(s): Uhram Song , EuiJae Kim , Jeong Hwan Bang , Deok Joo Son , Bruce Waldman , Eun Ju Lee
Green roofs recently have garnered much attention as a means to reduce both the absorption of solar energy in summer and heat loss in winter, especially in urban areas with limited space for gardening. Constructed wetland roofs maintain more stable temperature profiles than terrestrial systems because of their slow heat transfer and high heat storage capacity. We found that wetland roofs were particularly efficient at decreasing the temperature of green roof systems on hot days. Wetland plants have high evaporation rates that are associated with their ability to cool buildings. Constructed wetland had excellent water holding ability, requiring less than 400 l water/m2 of irrigation over the entire growing season, which was less than 20% of the expected irrigation requirement for terrestrial systems on green rooftops. Wetland macrophyte species demonstrated high tolerance to flooding and drought and showed great potential for regeneration by rhizomes, suggesting easy maintenance. Plants grown in the constructed wetland accumulated high biomass that can serve as a carbon sink. Wetlands on rooftops would not exceed the weight-bearing capacity of rooftops if water depths are designed and kept under 30 cm. Constructed-wetland roofs offer thermal benefits, a low amount of required irrigation, high tolerance of drought and flood, and flood-control capacities. They also can act as a carbon sink, are easy to manage, and provide other ecological services. Therefore, constructed wetlands are a reasonable choice for green rooftop systems.

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Practical correlation for thermal resistance of 45° sloped enclosed airspaces with downward heat flow for building applications

May 7, 2013, 5:40 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65
Author(s): Hamed H. Saber
A table is provided in the 2009 ASHRAE Handbook of Fundamentals (Chapter 26) that contains the thermal resistances (R-values) of enclosed airspaces. The ASHRAE table provides the R-values for enclosed airspaces of different thicknesses, effective emittances, mean airspace temperatures, and temperature differences across the airspaces. This table is extensively used by modelers, architects and building designers in the design for the R-values of building enclosures. The effect of the airspace aspect ratio (length/thickness) on the R-value is not accounted for in the ASHRAE table. However, previous studies showed that the aspect ratio of the airspace can affect its R-value. In this paper, the previous studies that focused on determining the R-values for vertical enclosed airspaces and horizontal enclosed airspaces with upward and downward heat flow are extended to investigate the effect of the aspect ratio on the R-values of 45° sloped enclosed airspaces under downward heat flow for different airspace thicknesses and having a wide range of values for the effective emittance, mean temperature, and temperature differences across the airspaces. The predicted R-values are compared with those provided in the ASHRAE table. Considerations are also given to investigate the potential increase in the R-values of enclosed airspaces when a thin sheet is placed in the middle of the airspace and whose surfaces have different values of emissivity. Thereafter, practical correlation is developed for determining the R-values of 45° sloped enclosed airspaces for future use by modelers, architects and building designers. The simplicity of this correlation for the sloped enclosed airspaces along with those that were previously developed for vertical and horizontal airspaces suggests that these correlations could be included in the ASHRAE Handbook of Fundamentals.

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Determination of dynamic intake fraction of cooking-generated particles in the kitchen

May 7, 2013, 5:40 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65
Author(s): Jun Gao , Changsheng Cao , Qianfen Xiao , Bin Xu , Xiang Zhou , Xu Zhang
This paper attempts to determine the individual intake fraction of particles generated from a simplified cooking process of edible oil heating in the kitchen. First, two separate sets of experiments, utilizing real-time Malvern particle sizer and TSI aerosol monitor, respectively, are combined to obtain the size-dependent emission rate of fume particles from the cooking process. Second, a drift flux model for particle dispersion, getting particle source-releasing conditions from the experimental data, is applied to predict the dynamic concentration in the kitchen. Third, size-dependent dynamic intake fraction of the particles by an individual in the kitchen, based on a breathing model defined, is determined from the predicted particle concentrations. It is found from the case studies that the inhaled particle concentration is highly attributed to the air distribution under different ventilation conditions of the kitchen space, even if both the ventilation rate and final capture efficiency of the exhaust system are the same. It is confirmed that different air inflow results in even different magnitude of intake fraction, ranged from ∼10−3 to ∼10−5. Lower intake fraction is observed under the open door conditions because inflow from the lower-level of the door produces some effect as the displacement ventilation. Results also show that size distribution of the inhaled mass is similar to that at the source, and the dynamic intake fraction is little sensitized to the particle size, due to the short-time and short-distance particle dynamics during the cooking process. The present work quantifies the attributed fraction of cooking-generated particles taken in by exposed individual through integrating the experimental and numerical methods. It helps to evaluate the indoor air quality and understand the health risk due to cooking activity in the kitchen space.

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Measuring the characteristic parameters of VOC emission from paints

May 10, 2013, 6:17 pm
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Publication date: Available online 9 May 2013
Source:Building and Environment
Author(s): Jianyin Xiong , Lixin Wang , Yuhua Bai , Yinping Zhang
The emission characteristic parameters of volatile organic compounds (VOCs) from paints are the initial concentration, the diffusion coefficient and the paint/air partition coefficient. It is necessary to determine these parameters for fully understanding the emission behaviors as well as for source control. Based on detailed mass transfer analysis of VOC emissions from paints, a novel method is developed to measure these parameters, which owns the following merits: (1) the diffusion coefficient and partition coefficient can be simultaneously determined; (2) it takes less than 12h for the cases studied and indicates high measurement accuracy (R2 in the range of 0.921-0.939). Ventilated chamber experiments are performed to obtain the two parameters of methylcyclohexane and toluene emissions from one kind of solvent-based paint. The effectiveness of the method is verified by the good agreement between model predictions based on the determined characteristic parameters and experiments. The present approach is then applied to analyze the experimental data in the literature, and good results are also obtained, which further demonstrates that the approach is convincing and reliable. Our new approach should prove useful for rapid prediction and characterization of VOC emissions from paints as well as from other wet materials.

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Infiltration or indoor sources as determinants of the elemental composition of particulate matter inside a school in Wrocław, Poland?

May 10, 2013, 6:17 pm
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Publication date: Available online 9 May 2013
Source:Building and Environment
Author(s): Anna Zwoździak , Izabela Sówka , Barbara Krupińska , Jerzy Zwoździak , Alicja Nych
Children’s exposure to air pollution requires a focus on air quality in places where they spend most time, e.g. in schools. Therefore, understanding how indoor elemental concentrations relate the outdoor ones is necessary to create healthy indoor school environment. The aims of this study were to examine the elemental composition of particulate matter (PM1, PM2.5, PM10) in the school and also to investigate to what degree indoor elemental concentrations are affected by outdoor air or generated inside the school. The measurements were performed inside and outside the public school building in the centre of the city.It was observed that concentrations of most elements were higher at school than outside. The dominant elements in PM1 both indoors and outdoors were S, Cl, K, and Zn. PM2.5 and PM10 fractions inside the school were clearly enriched in elements of mineral origin, additionally S, Zn, K and Cl were also present in high concentrations both indoors and outdoors. Results suggested that a significant contribution to indoor Zn, Pb and S concentrations in the PM2.5 fraction was from penetration of outdoor air. 88%, 80% and 90% of the observed total variations in indoor concentrations of Zn, Pb, and S were explained by the linear relationship between indoor and outdoor concentrations. The lack of correlation between indoor and outdoor concentrations obtained for Si, Ca, Ti, Sr indicated that these metals were more likely to originate from indoor sources.

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Impact of climatic conditions on the thermal effectiveness of an extensive green roof

May 10, 2013, 6:17 pm
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Publication date: Available online 9 May 2013
Source:Building and Environment
Author(s): Bau-Show Lin , Chin-Chung Yu , Ai-Tsen Su , Yann-Jou Lin
The density of urban development has been the source of a number of environmental issues, and in urban areas with large quantities of stereoscopic space, roof greening has become an important strategy for land compensation and environmental quality improvement. In particular, with the intensification of urban heat island and the global warming phenomena, the effective regulation of the microclimate by building a green roof becomes more attractive. Because a green roof is closely related to the climate and the environment, the main purpose of this study is to explore the impact of climatic conditions on the thermal effectiveness of an extensive green roof. The experimental cases of an extensive green roof were individually established in urban areas with both sub-tropical and tropical island climates, and synchronous observations were made. The research results show that it can reduce the increase of outdoor temperature by approximately 42% and the increase of the indoor temperature by 8% during the daytime. During the night, it can maintain 17% of the temperature in the outdoor environment, stabilizing the temperature change. The thermal effectiveness of an extensive green roof is closely related to the climate. The daytime cooling effectiveness was relatively high in the tropical island climate in summer, and the nighttime insulation effectiveness was more pronounced in the sub-tropical climate. Rainfall reduced the thermal effectiveness of an extensive green roof.

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Field investigation of comfort temperature in Indian office buildings: A case of Chennai and Hyderabad

May 10, 2013, 6:17 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65
Author(s): Madhavi Indraganti , Ryozo Ooka , Hom B. Rijal
India's building energy consumption is increasing rapidly. The subcontinent does not have custom made thermal comfort standards. There is little research in this field in the last 26 years. This leaves a lot to be investigated. We conducted a thermal comfort field study in 25 office buildings in Chennai and Hyderabad for seven months during the summer and south west monsoon seasons in 2012 and collected 2612 datasets from 1658 subjects. The comfort temperature in naturally ventilated (AC off) (NV) mode was 27.6 °C and 28.1 °C in Chennai and Hyderabad respectively. In air conditioned (AC) mode, it was 27.0 °C and 26.1 °C in these two cities. These departed from the limits in the Indian National Building Code. Chennai recorded significantly higher indoor air speeds and thus higher comfort temperature. In 71% cases the air speed was less than 0.15 m/s, underscoring the need for improvement. A majority always sensed the air movement low and desired increased air speeds, despite voting comfortable. Both the States grappled with daily outages throughout the survey period. All the buildings, excepting two were forced to run without the AC at least for 2 h daily, while none were prepared well for this. Several design and non-design factors seriously impeded environmental adaptation in buildings, limiting the adaptive operation of windows and fans. Consequentially, thermal acceptability was generally low (62.5%). This calls for architect's serious attention towards environmental and thermal adaptation in buildings, in the era of power paucity and prudent consumption.

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A novel model for risk assessment of adjacent buildings in tunneling environments

May 10, 2013, 6:17 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65
Author(s): Limao Zhang , Xianguo Wu , Lieyun Ding , Miroslaw J. Skibniewski
This paper presents a novel model to assess the risk of adjacent buildings in tunneling environments based on Extended Cloud Model (ECM). ECM is an organic integration of Extension Theory (ET) and Cloud Model (CM), where ET is appropriately employed to flexibly expand the variable range from [0, 1] to (−∞, +∞), and CM is used to overcome the uncertainty of fuzziness and randomness during the gradation of evaluation factors. An integrated interval recognition approach to determine the boundary of risk related intervals is presented, with both actual practices and group decisions fully considered. The risk level of a specific adjacent building is assessed by the correlation to the cloud model of each risk level. A confidence indicator θ is proposed to illustrate the rationality and reliability of evaluating results. Ten buildings adjacent to Wuhan Metro Line Two (WMLT) are randomly chosen among hundreds of adjacent buildings for a case study, and the results have proved to be consistent with the actual situation. Compared with other traditional evaluation methods, ECM has been verified to be a more competitive solution with no demands on training data. The original data can be directly entered into ECM without a normalization procedure, avoiding the potential information loss. ECM can be offered as a decision support tool for the risk assessment in urban tunneling construction and worth popularizing in other similar projects.

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The effect of cyclic moisture and temperature on mould growth on wood compared to steady state conditions

May 10, 2013, 6:17 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65
Author(s): Pernilla Johansson , Gunilla Bok , Annika Ekstrand-Tobin
Moisture and temperature are the two key environmental parameters that determine the possibility of mould growth on building materials. The time that the material is exposed to these elements is also crucial. The natural environmental conditions of relative humidity and temperature are seldom constant over prolonged time periods in a building. Instead, they vary over time, with fungi encountering both favourable and unfavourable conditions; such variable conditions affect mould growth. This paper reports findings from a laboratory study in which mould growth at alternating RH (between 90% and 60%) or temperature conditions (between 22 °C and 5 °C) was studied and compared to steady state conditions. Fluctuating RH led to slower mould growth, and when the period of unfavourable/favourable conditions was longer (1 week), growth was affected more than if the duration of these conditions was short (12 h). When alternating the temperature weekly between 22 °C and 5 °C, with a mean of 13 °C, the mould growth rate was lower compared to when the temperature was held constant at 22 °C. The mould growth under fluctuating temperature conditions was comparable to when the temperature was kept constant at 10 °C.

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Methods for detailed energy data collection of miscellaneous and electronic loads in a commercial office building

May 10, 2013, 6:17 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65
Author(s): Steven Lanzisera , Stephen Dawson-Haggerty , H.Y. Iris Cheung , Jay Taneja , David Culler , Richard Brown
Miscellaneous and electronic loads (MELs) consume about 20% of the primary energy used in U.S. buildings, and this share is projected to increase for the foreseeable future. Our understanding, however, of which devices are most responsible for this energy use is still rudimentary due to the difficulty and expense of performing detailed studies on MELs and their energy use. In order to better understand the energy use of MELs and the design of MELs field metering studies, we conducted a year-long study of MELs in an 89,500 sq. ft. (8310 m2) office building. We present insights obtained from this study using 455 wireless plug-load power meters including the study design process, the tools needed for success, and key other methodology issues. Our study allowed us to quantify, for the study buildings, how many devices we needed to inventory and meter as well as for how long we needed to collect meter data. We find that the study design of earlier work would not have yielded accurate results in our study building. This paper presents these findings along with a brief summary of the energy related results.

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A model of vegetated exterior facades for evaluation of wall thermal performance

May 11, 2013, 7:40 pm
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Publication date: Available online 11 May 2013
Source:Building and Environment
Author(s): Irina Susorova , Melissa Angulo , Payam Bahrami , Brent Stephens
A mathematical model of an exterior wall covered with climbing vegetation has been developed to evaluate the thermal effects of plants on heat transfer through building facades. This model allows for analysis of how various plant physiological parameters such as leaf area index, average leaf dimension, and leaf absorptivity can improve facade thermal performance by reducing the exterior wall surface temperatures and heat flux through the façade. The model has been verified with a set of experiments that measured both bare and vegetated facade thermal performance of an educational building in Chicago, IL, during the summer. A sensitivity analysis was also conducted to elucidate the relative impacts of plant characteristics, weather conditions, climate zones, wall assemblytypes, and facade orientation on vegetated facade thermal performance. Overall, results herein show that a plant layer added to the facade can improve its effective thermal resistance by 0.0-0.7 m²K/W, depending on a range of inputs for wall parameters, climate zones, and plant characteristics (particularly leaf area index). These improvements are especially pronounced in predominantly warm climates with high solar radiation and, to a lesser extent, low wind speeds. The model developed herein can ultimately be used both to access facade thermal improvements in existing buildings retrofitted with green walls and to design green walls for optimal energy efficiency in new construction.

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The activity of acrylic-silicon/nano-TiO2 films for the visible-light degradation of formaldehyde and NO2

May 12, 2013, 8:20 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65
Author(s): Gang Xiao , Anna Huang , Haijia Su , Tianwei Tan
Through a novel green and low-cost emulsion blend method, acrylic-silicon/nano-TiO2 films (ASTF) were prepared showing a broad absorption band in the visible light region and could be used for the photodegradation of indoor gaseous pollutants under visible light irradiation. Compared with acrylic-silicon films, the photodegradation rate of ASTF with TiO2 content of 1% (w/v) increased by almost twice for both gaseous formaldehyde (from 28% to 76.7% at the initial concentration of 0.8 mg/m3) and NO2 (from 20% to 68% at the initial concentration of 3.7 mg/m3) under visible light irradiation for 24 h and 50 h, respectively. The binary gas degradation confirmed the higher affinity of NO2 for ASTF. In addition, ASTF with FeⅢ ion doping (<100 mg/L) showed even higher photocatalytic activity with maximum degradation rate of 83.4% for formaldehyde under visible light irradiation for 24 h. ASTF, as a kind of eco-friendly coating material, could be used easily in domestic buildings for our daily life.

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Health and Economic Implications of Natural Ventilation in California Offices

May 13, 2013, 9:23 pm
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Publication date: Available online 13 May 2013
Source:Building and Environment
Author(s): Spencer M. Dutton , David Banks , Sam L. Brunswick , William J. Fisk
This study examines the human health implications of natural ventilation in California office buildings. We modeled work-time exposures using field data on indoor and outdoor ozone and particulate matter from four case studies in naturally ventilated offices and published data from mechanically ventilated offices. We also modeled the amount of time that windows would be open in the naturally ventilated office and used the results to estimate the difference in pollutant exposures for occupants of naturally ventilated versus mechanically ventilated, air-conditioned offices. Based on published concentration-response equations, we estimated the incremental changes in health outcomes that resulted from the difference in exposures for occupants in the two types of offices. We also estimated the differences in sick building symptom rates based on symptom prevalence rates in naturally ventilated and air-conditioned offices. Finally, we developed first-order estimates of the health-related costs and benefits of retrofitting 10 percent of California’s current office space to use natural ventilation. Findings included an increase in annual health-related costs from increased exposure to ozone and particulate matter of between $130 million and $207 million, and a reduction in sick building syndrome symptom costs, valued between $4.3 million and $11.5 million. Our estimates have a high degree of uncertainty and exclude potentially significant health-related costs and benefits of both naturally ventilated and air-conditioned buildings. Nonetheless, these estimates indicate that health-related costs of natural ventilation are significant and warrant further study. We also explore several mitigation options that could limit the health and economic impacts of natural ventilation.

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Experimental evaluation of VOC removal efficiency of a coconut shell activated carbon filter for indoor air quality enhancement

May 13, 2013, 9:23 pm
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Publication date: Available online 13 May 2013
Source:Building and Environment
Author(s): E. Gallego , F.J. Roca , J.F. Perales , X. Guardino
The present study evaluated the performance of a commercially available activated carbon filter for VOC removal from air through the analysis of real samples. The filter was tested for VOC reduction efficiencies in a PVC portable inflatable bubble provided with an air purifier system called Airbox II Phase by Zonair3d, as described hereinafter. The filter was placed in the Airbox II Phase of the bubble, between a pre-filter and a particulate HEPA H14 filter. Simultaneous duplicate samples were taken from the input air duct before the driving system and from the bubble. VOC were dynamically sampled during 2-hour control periods by connecting custom packed glass multi-sorbent cartridge tubes (Carbotrap, Carbopack X and Carboxen 569) to air pump samplers. A validated analytical method based on TD-GC/MS was used to quantify a wide variety of VOC families (alkanes, aromatic hydrocarbons, alcohols, ketones, halocarbons, aldehydes, esters, terpenes, ethers, glycols and nitrogenated compounds). VOC family removal efficiencies ranged from 51 ± 19% to 78 ± 22% with input indoor air, and from 42 ± 16% to 91 ± 18% with input outdoor air. No significant differences in reduction efficiencies (t-test; p<0.05) were observed between using indoor or outdoor air. Several aldehydes were desorbed from the filter at low concentrations (0.09 to 21.19 μg m-3) when outdoor air was used as input air. Ozone removal efficiency was assessed by a continuous monitoring system. A 100% yield was obtained in all cases where ozone was present.

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An algorithm to predict the transient moisture distribution for wall condensation under a steady flow field

May 14, 2013, 11:08 pm
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Publication date: Available online 14 May 2013
Source:Building and Environment
Author(s): Xiaojun Ma , Xianting Li , Xiaoliang Shao , Xuan Jiang
The prediction and control of the indoor moisture distribution, especially for wall condensation, is very important for a healthy and energy-efficient environment. However, existing methods cannot accurately predict the transient indoor moisture distribution for wall condensation. In this study, the prediction of indoor transient moisture distribution is facilitated by using transient accessibility indices, which characterize the transport of the passive contaminants to describe boundary effects on the transient moisture distribution. An algebraic expression is obtained for the indoor moisture distribution, and a computational model is presented for the wall condensation problem. The model is validated by experiments and computational fluid dynamics (CFD) simulations, and the model is implemented for a wall condensation case study. The new model can easily predict the indoor moisture distribution under different boundary conditions and for a range of condensation time on the wall surfaces. This study provides an effective means of indoor moisture prediction and control, which may become an important tool for designing a non-uniform indoor environment.

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Air quality and relative humidity in commercial aircrafts: an experimental investigation on short-haul domestic flights

May 17, 2013, 11:52 pm
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Publication date: Available online 17 May 2013
Source:Building and Environment
Author(s): Carlo Giaconia , Aldo Orioli , Alessandra Di Gangi
Nowadays the achievement of a comfortable environment in aircraft cabins is a factor of paramount importance in air travel business competition; on the other hand, the need of reducing the propulsion fuel cost has driven the airline companies to adopt air handling systems that may reduce the levels of thermal comfort and air quality inside the cabins of commercial airliners. With the aim of contributing to a better knowledge of this matter, this paper reports the results of an experimental study upon the indoor air quality aboard commercial aircrafts for 14 domestic flights less than one hour and half long. The parameters monitored were temperature, relative humidity and carbon dioxide concentration; the measurements were performed during the whole flight from the take-off to the landing. The relative humidity inside the cabin was also calculated using the rates of outside air and the carbon dioxide as a ventilation tracer; the theoretical results were compared with the measured data. The relationship between relative humidity and carbon dioxide concentration during fights was highlighted in order to define the environmental conditions that may provide acceptable levels of both the air quality and hygrometric comfort to the crew and passengers. The results of calculations confirmed the possibility of improving the hygrometric conditions in aircraft cabins without the need of using humidification systems.

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An alternative method for evaluating the air tightness of building components

May 17, 2013, 11:52 pm
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Publication date: Available online 17 May 2013
Source:Building and Environment
Author(s): Osama A.B. Hassan
In this study, an alternative and general approach is advanced to evaluate the air leakage area and air infiltration rate in building envelope components such as exterior/internal walls and floors. In this method, the leakage area is determined with the help of acoustical and physical methods by measuring the sound reduction index of the building. The air flow rate through air leaks is determined with the help of leakage area and pressure difference over the floor/wall. The heat losses and convective moisture rate through leaks in the building are subsequently evaluated with the help of the calculated air infiltration rate.

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Editorial Board

May 17, 2013, 11:52 pm
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Publication date: July 2013
Source:Building and Environment, Volume 65



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Elemental modeling of adsorption filter efficiency for indoor air quality applications

May 17, 2013, 11:52 pm
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Publication date: August 2013
Source:Building and Environment, Volume 66
Author(s): Razvan Stefan Popescu , Patrice Blondeau , Eric Jouandon , J.C. Costes , J.L. Fanlo
Adsorption based air cleaning technologies have long been employed in various industrial applications but it has remained marginal in office and residential buildings. The present study presents a first step in the development of physically-based models that could help civil engineers to improve the design and maintenance of such systems by considering the complexity of the indoor air cleaning problem, especially variable concentrations, temperature and airflow rate. The breakthrough curves of six challenge gases in a packed bed of non-treated granular activated carbon were measured for gases as singles, and then as a mixture, in dry air and under isothermal conditions. On the whole, the results indicate good agreement between measured and predicted concentrations at the filter outlet. Considering the large number of contaminants that can be found in indoor settings, this suggests that the questions of efficiency and lifetime of the filter are probably much more difficult to answer than one can think. Finally, the paper discusses some possible improvements of the models as a way to increase accuracy, but also to allow for the simulation of even more realistic configurations of filter operation.

Highlights

► Fundamentals of adsorption dynamics in activated carbon filters, for indoor air quality applications. ► Heat and mass transfer model validated with experimental data, in dry conditions. ► The model is able to simulate in realistic configurations of operation, with variable inlet parameters.
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