Airflow In Buildings Research Articles

Recent advances and effectiveness of machine learning models for fluid dynamics in the built environment

ABSTRACT Indoor environmental quality is crucial for human health and comfort, necessitating precise and efficient computational methods to optimise indoor climate parameters. Recent advancements in machine learning (ML) and computational fluid dynamics (CFD) are promising. However, applying ML to complex building airflow presents challenges. This research aims to investigate the integration of ML with CFD in the context of built environment applications using a systematic review approach. It highlights a critical knowledge gap: the need to synthesise innovative approaches that address the limitations of indoor modelling using data-driven ML methods. The review examines contemporary literature, identifying current developments and suggesting potential future directions. It delves into the innovations in combining ML with CFD to predict thermal comfort and indoor air quality, uncovering key limitations such as the lack of high-quality experimental data for training and validation, the computational complexity of detailed CFD simulations, and the interpretability issues of ‘black-box’ ML models. The emergence of data-driven techniques in fluid mechanics offers promising prospects for modelling in the built environment. Future research should focus on incorporating physics-based rules in ML models, adapting turbulence closure models for indoor flows, and enhancing model validation using real-world datasets. The research emphasises the synergistic relationship between ML and CFD; it proposes pathways to overcome current limitations, aiming to enhance the precision and efficiency of indoor environment modelling through their integration.

CFD Simulations of Small Particle Behavior with Blower-Driven Airflows in Single-Family Residential Buildings

Inhaling airborne droplets exhaled from an infected person is the principal mode of COVID-19 transmission. When residential energy efficiency workers conduct blower door tests in occupied residences with a COVID-19-infected occupant potentially present, there is a concern that it could put the workers at risk of infection with massive flows of air being generated by the tests. To minimize this risk, computational fluid dynamics (CFD) simulations were conducted for four prototype houses to develop guidelines for workers to follow during their service visits. The CFD simulations visualized the movements and evaluated the residence time of small particles released at certain locations under a series of scenarios representing situations that are likely to be encountered during in-home energy efficiency services. Guidelines were derived from the simulated tracks of droplets to help to increase the safety of the worker(s).

Data-driven prediction of indoor airflow distribution in naturally ventilated residential buildings using combined CFD simulation and machine learning (ML) approach

Predicting indoor airflow distribution in multi-storey residential buildings is essential for designing energy-efficient natural ventilation systems. The indoor environment significantly impacts human health and well-being, considering the substantial time spent indoors and the potential health and safety risks faced daily. To ensure occupants’ thermal comfort and indoor air quality, airflow simulations in the built environment must be efficient and precise. This study proposes a novel approach combining Computational Fluid Dynamics (CFD) simulations with machine learning techniques to predict indoor airflow. Specifically, we investigate the viability of employing a Deep Neural Network (DNN) model for accurately forecasting indoor airflow dispersion. The quantitative results reveal the DNN’s ability to faithfully reproduce indoor airflow patterns and temperature distributions. Furthermore, DNN approaches to investigate indoor airflow in the residential building achieved an 80% reduction in the time required to anticipate testing scenarios compared with CFD simulation, underscoring the potential for efficient indoor airflow prediction. This research underscores the feasibility and effectiveness of a data-driven approach, enabling swift and accurate indoor airflow predictions in naturally ventilated residential buildings. Such predictive models hold significant promise for optimizing indoor air quality, thermal comfort, and energy efficiency, thereby contributing to sustainable building design and operation.

The Effects of Rhythm on Building Openings and Fenestrations on Airflow Pattern in Tropical Low-Rise Residential Buildings

Effective passive airflow in low-rise residential buildings in hot-humid environment is crucial to maintaining good indoor thermal comfort for occupants. However, investigation of effects of the rhythm of window openings on achieving a passive airflow pattern in such buildings in the tropical climate of sub-Saharan Nigeria have been rarely studied. Therefore, this research aimed to evaluate the effects of the rhythm of window openings on passive airflow patterns for indoor thermal comfort in low-rise residential buildings in the hot-humid environment of Obosi, Nigeria. It involved experimental research using the Anemometer TA465 instrument for measuring wind velocity, relative humidity, and temperature of the purposively designated buildings in the three layouts of the study area for both wet and dry seasons. Employing the Yamane statistical formula, a sample size of 433 was obtained, and questionnaires were administered to occupants of the studied buildings and analyzed using categorical Regression Analysis (CATREG). The regression analysis showed that p=0.000, i.e. p<0.05 indicating that there was a significant relationship between the type and sizes of windows (elements used in measuring rhythm) and the intensity or force of breeze (a measure of passive airflow pattern). Further analysis of the data involved the use of Autodesk CFD 2018 (Computational Fluid Dynamics) for building wind flow simulations. The result showed variations in temperature levels (indications of differences in indoor thermal comfort) of various indoor spaces of the investigated designated floors and buildings, especially ground floors and the top-most floors of the buildings. The study underscored the need to use architectural rhythm design strategies to create a positive impact on airflow patterns in low-rise buildings, especially in densely built-up urban areas. The results of this study are instructive in noting that in order to attain passive airflow in buildings in the face of challenge of land restrictions, vertical stacking of building floors could be used once an adequate rhythm of window openings is adopted. Doi: 10.28991/CEJ-2023-09-08-016 Full Text: PDF

A Sensing-Based Visualization Method for Representing Pressure Distribution in a Multi-Zone Building by Floor.

Airflow in a multi-zone building can be a major cause of pollutant transfer, excessive energy consumption, and occupants discomfort. The key to monitoring airflows and mitigating related problems is to obtain a comprehensive understanding of pressure relationships within the buildings. This study proposes a visualization method for representing pressure distribution within a multi-zone building by using a novel pressure-sensing system. The system consists of a Master device and a couple of Slave devices that are connected with each other by a wireless sensor network. A 4-story office building and a 49-story residential building were installed with the system to detect pressure variations. The spatial and numerical mapping relationships of each zone were further determined through grid-forming and coordinate-establishing processes for the building floor plan. Lastly, 2D and 3D visualized pressure mappings of each floor were generated, illustrating the pressure difference and spatial relationship between adjacent zones. It is expected that the pressure mappings derived from this study will allow building operators to intuitively perceive the pressure variations and the spatial layouts of the zones. These mappings also make it possible for operators to diagnose the differences in pressure conditions between adjacent zones and plan a control scheme for the HVAC system more efficiently.

Quantifying suite-level airtightness in newly constructed multi-unit residential buildings using guarded suite-level air leakage testing

Improving inter-zonal airtightness in multi-unit residential buildings (MURBs) has wide-ranging benefits including reduced odour/pollutant transfer, reduced sound transmission, and improved energy efficiency. The current metric used to assess inter-zonal airtightness in MURBs is the unguarded air leakage rate, which measures the air leakage through all interior and exterior suite boundaries. While this metric provides a general indication of overall suite airtightness, it provides no information on the location or distribution of leakage pathways across the individual suite partitions. Depending on the construction type(s) of suite partitions there may be variability in air leakage rates at the partition level, which is masked by the whole-suite metric. This makes it difficult to identify potential areas for improvement in design and construction practices.Guarded blower door testing was completed in 14 suites in six newly constructed/renovated MURBs, in Southern Ontario, Canada. Whole-suite air leakage rates for the sample were generally low, consistent with previous studies. Broken down by partition type, floor/ceiling and suite-to-suite walls exhibited similar levels of airtightness, with sample means of 0.36L/s/m2 and 0.32L/s/m2, respectively, at 50Pa (0.07cfm50/ft2 vs. 0.06cfm50/ft2). In contrast, the average suite-to-corridor wall air leakage rate was nearly eight times higher (2.46L/s/m2 (0.49cfm50/ft2)). The results highlight the need to develop targeted air sealing strategies to improve suite-to-corridor wall air leakage rates. Recommendations for improving inter-zonal air sealing practices in new construction are discussed. The measurements reported in this work will also help to improve building airflow simulations, which rely on partition-level air leakage metrics for model inputs.

Occupant's preferred indoor air speed in hot-humid climate and its influence on thermal comfort

As an energy-efficient and high-comfort indoor environment control method, the rational application of airflow in modern buildings has brought renewed attention, especially in hot and humid areas. Chamber experiments were conducted to examine occupants’ preferred air speed and its effects on thermal comfort in hot-humid climate, and the extended thermal comfort zone limit was obtained. Three temperature levels (26 °C, 29 °C, and 32 °C) and two relative humidity levels (40%–60% and 70%–90%) were set, achieving six experimental conditions. During each condition, thirty-six participants were sequentially exposed to two stages with still air and personal controlled stable mechanical airflow produced by electric fans, each lasting 30 min. Their subjective perceptions were collected repeatedly, and skin temperature was measured continuously. For the six conditions, the average preferred air speeds were estimated to be 0.53 m/s, 0.62 m/s, 1.06 m/s, 1.31 m/s, 1.28 m/s, and 1.48 m/s respectively. The preferred air speed at high humidity (70%–90%) was approximately 0.15 m/s-0.3 m/s higher than that at moderate humidity (40%–60%), and such difference increased with air temperature. Elevated air speeds may be used to offset thermal discomfort, as indicated by a 0.2°C–0.5 °C significant decrease in the mean skin temperature and improvements in subjective perceptions. However, for extremely hot and humid conditions including 29 °C/85%, 32 °C/55%, and 32 °C/85%, the discomfort cannot be completely eliminated. When local control of airflow is provided to occupants, the acceptable operative temperature range could be extended by approximately 1 °C regardless of humidity, compared with that under near still air speed below 0.1 m/s.

Computational fluid dynamics for cross‐ventilated airflow in an urban building

AbstractIn this study, the velocity field in a naturally ventilated building within an urban‐like array was explored using large‐eddy simulations. Reduced‐scale building models were used to examine the impacts of the geometric conditions in the surrounding buildings and cross‐ventilating windows on the flow statistics and instantaneous velocity fields in the sheltered building. The instantaneous velocity components averaged in the opening area were calculated for each condition of the building arrays and openings. The results indicate that the surrounding urban geometry significantly affects the turbulent opening velocities. Additionally, the three‐dimensional instantaneous velocity distributions within the target building clearly demonstrate considerable differences under the different building and opening conditions. Such differences also affect the mean, maximum, and minimum wind speeds within the indoor regions. Moreover, the distributions of the two‐point correlation coefficient (defined by the velocities normal to the windows at the center of the windward opening and inside the building) were compared for each condition. The strong correlations near the two openings indicate that the instantaneous velocity generated by the surrounding buildings is an important factor in determining the statistical and instantaneous features of indoor ventilating airflows.

Field measurement and numerical investigation of natural cross-ventilation in high-rise buildings; Thermal comfort analysis

The importance of climate change mitigation and energy efficiency as a growing global concern has intensified the development of techniques to reach and improve thermal comfort and energy efficiency of buildings. The study of the effect of the height of the openings on the internal natural airflow in one-story buildings can be found in many studies; However, studies on the effect of this important factor on providing thermal comfort in high-rise buildings equipped with DSF are not available. This paper focuses on natural-ventilated buildings based on wind-driven and buoyancy-driven forces. The aim of this study is to use passive strategies in high-rise office buildings in hot and dry climates. In this research, two methods of field studies and numerical modeling have been used in order to provide accurate results. In order to achieve optimal patterns in the design of natural-ventilated buildings; CFD simulation and PMV thermal comfort index have been used in the evaluation of various configurations. The results of the present study show that although the cooling energy demand in high-rise buildings in hot climates is high and the use of natural ventilation systems is beneficial, but these systems alone are not able to provide thermal comfort conditions. However, the accurate and correct location of the openings is effective in improving thermal comfort by increasing the volume flow.

Thermal Draft Load Coefficient for Heating Load Differences Caused by Stack-Driven Infiltration by Floor in Multifamily High-Rise Buildings

The stack effect is dominant in multifamily high-rise buildings (MFHRBs) in winter because of the considerable height of MFHRBs, which causes a difference in the infiltration amount between floors. This difference causes a heating load difference between floors in a MFHRB. However, there are no indicators to quantify the heating load differences in previous studies. In this article, an indicator—the thermal draft load coefficient (TDLC)—is proposed that can be used to estimate and evaluate the differences between floors in a MFHRB. The TDLC is built on a theoretical model of the stack effect and leakage area of the airflow paths, considering the entire building airflow in a MFHRB. The theoretical model was validated by comparison with a simulation model. The winter average coefficient of variation of the root mean square error and the normalized mean bias error of the theoretical model were acceptable (17.1% and 9.3%, respectively). The TDLC resulted in a maximum of 2.5 and a minimum of approximately 0.1 in the target MFHRB. The TDLC can pre-evaluate the load difference in the building design stage and can be utilized to build design standards or guidelines.

Wind tunnel modeling experiments on airflow characteristics of underground metro station with sunken squares

Building airflow characteristics can affect the indoor air environment, thereby affecting indoor air quality and building energy consumption. In recent years, the sunken square has increasingly designed and applied to underground transportation hub systems, because of their special advantages, such as improving the ventilation and lighting of the underground space, blurring the feeling of the ground and underground and improving the quality of the space. However, at present, there are few systematic and comprehensive researches on the airflow characteristics of the sunken squares to the underground metro station. In this study, the wind tunnel modeling experiment and the particle image velocity (PIV) technology are comprehensively used to study the influence of the sunken square on the airflow characteristics of the underground metro station, the influence of the sunken square on the flow field distribution and air exchange rate of underground metro station are obtained. The dimensionless average wind velocity at the large openings of the sunken square is 0.053-0.18, and the air exchange rate of the underground metro station is changed with the number and the relative positions of sunken squares. Conclusions of this research could provide useful reference to the design of airflow characteristics for underground buildings.

A multi-zone, fast solving, rapidly reconfigurable building and electrified heating system model for generation of control dependent heat pump power demand profiles

The electrification of heating is expected to grow in the UK domestic sector, and this has increased interest in the effects that this may have on low and high voltage network operation. However, Electrified heating profiles that alter with control decisions can only be obtained from dedicated building modelling that energy system modellers do not usually have the expertise to perform, yet these are required for meaningful studies. This work outlines a novel method for modelling air source and ground source heat pump power demand profiles using a multi-zone physics based building modelling framework with building fabric, thermohydraulic, and air flow subsystems. The novel setup framework allows detailed building layout, fabric and control properties to be assigned by analysts with no prior building modelling expertise. Once fully assigned, the building model can be used to generate heat pump power demand profiles at sub minute resolution. Upon testing, a single daily run of the model could be executed in 17 s. The model was then validated against real life test house data, under various control and weather conditions. A small relative error (typically within 10%) was observed between modelled and actual cycle lengths, and modelled and actual heat and electricity demands. Due to its rapid solution rate, the model is of significant value to energy efficiency and distribution network studies, where large demand profile sets that are sensitive to detailed retrofit and control considerations are often essential. The model has been made openly available.

Indoor airflow and thermal comfort in a cross-ventilated building within an urban-like block array using large-eddy simulations

This study characterizes the indoor airflow and occupants’ thermal sensations in a cross-ventilated building model sheltered by generic cube arrays based on large-eddy simulations (LESs). Four ventilation models, which comprise different cross-ventilating openings, streamwise (STR) and lateral (LAT) windows, and block arrangements, lattice-type square (SQ) and staggered (ST) patterns, were examined to understand the following geometry-oriented features: i) the temporal and spatial deviations of wind speed at openings and inside the ventilation models, ii) effects of time and space resolutions for the velocity data on the estimation accuracy of the ventilation rate, and iii) predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) indices calculated with elaborately simulated velocity data. The difference in distribution of fluctuating normal velocity at openings was more significant when varying the conditions of the opening locations than that observed when varying the building arrangements. Therefore, the ventilation rates in the STR conditions were reasonably estimated using only the time-averaged flow rate at the center position of the windward opening; meanwhile, when the contributions of reverse flow were ignored at the openings, the ventilation rates in the LAT conditions were drastically underestimated using highly resolved velocity data at openings. Based on the thermal comfort assessment at an air temperature of 26°C, the discrepancies of area-averaged PMV values between STR and LAT cases were within 0.7 and 0.9 at the lower and middle heights of naturally ventilated buildings, resulting in a 5% difference in the PPD values.

Study of the design principles of residential buildings in a moderate and humid climate with a natural ventilation approach (Case study: Analysis of simulated openings of a residential building in Amol city)

Background and Objective: Inattention to the climatic features of different regions and the absence of sufficient knowledge of the design principles for optimal use of the potentials of the natural environment leads to higher costs and waste of energy in various fields. Accordingly, due to high humidity in Amol and high cost of ventilation and reduction of moisture in summer, the main objective of this research is to examine and analyze the simulated openings of a residential building with a natural ventilation approach. Method: the present study was carried out in the first step by reviewing the subject literature on this issue and identifying the concepts and principles of residential building design in the field of energy. Then, by supplying the climate information file of Amol from the Weather Meteorology Center for the Climate Consultant software, Design elements were presented. Subsequently, the components were analyzed by Expert Choice software based on the AHP method and computation of component weight led to the final decision in choosing the most important component. Finally, with the simulation of the building in the Flow Design software, the impact of natural ventilation on residential slopes was investigated. Findings: seven components were extracted from the above software as principles of the design and tables of climate interpretation. In the following, with the hierarchical analysis method (AHP), a natural ventilation component with a weight of 0.399 was found to be the main component of the static solar power system. Discussion and conclusion: A natural ventilation pattern was designed in a building with a sloping roof and specific dimensions in the Amol climate. By changing the layout of two 1-square-meter openings on two walls with a height of 2.7 meters in opposite directions at two heights of 1 and 1.7 meters from the floor of the building, 4 airflow modes were simulated with regard to the wind speed of the area in the Flow Design software. In this simulation, by placing the wind tunnel perpendicular to two walls, it can be stated that the best natural ventilation efficiency from these four conditions, is the one with two under-roof structures at 1.7-meter height with the highest wind-suction coefficient of 1.19, which will make a reasonable ventilation and air flow in the simulated residential building.

Suite-level air tightness and compartmentalization in multi-unit residential buildings: How do we achieve our intended goals?

Control of inter-zonal air flow in multi-unit residential buildings (MURBs) is currently regulated by ASHRAE 62.2: Ventilation and Acceptable Indoor Air Quality in Residential Buildings, which specifies a maximum whole-suite air leakage rate, normalized by surface area. Despite the fact that the compartmentalization requirement has been in effect since 2013, few studies have explicitly examined the feasibility of the requirement in concrete MURBs. This paper presents results from recent inter-zonal air leakage testing completed in 12 newly constructed MURBs located in southern Ontario, Canada (N = 175). Normalized air leakage under an induced pressure difference of 50Pa (q50) ranged between 0.16 and 2.51 L/s/m2 (0.03 and 0.49cfm/ft2) of total suite surface area with a mean equal to 0.49 L/s/m2 (0.10cfm/ft2), well below ASHRAE 62.2's limit of 1.52 L/s/m2 (0.30 cfm/ft2). However, guarded blower door testing in concrete MURBs revealed large disparities between the various suite boundary types, suggesting that the whole-suite air leakage rate may not provide sufficient information about partition-based air tightness to identify potential performance issues. While guarded blower door testing provides more useful air tightness data, it is very labour-intensive and time-consuming. Completing the test prior to general occupancy improved testing efficiency slightly; however, new logistical concerns arose when testing on an active construction site. Lessons learned and recommendations for future testing efforts are discussed.

Impact of opening shape on airflow and pollutant dispersion in a wind-driven cross-ventilated model building: Large eddy simulation

Natural ventilation, a useful mechanism to moderate the indoor temperature and to disperse pollutants, is a complex engineering problem to analyze due to a large number of influential factors such as wind direction, size, and location of openings, etc. The present paper investigates the effect of different shapes of openings, with a constant wall porosity, namely, horizontally long, squared and vertically long, on cross-ventilation in a generic isolated building. Flow and passive pollutant concentration fields are the performance indicators. The large eddy simulation (LES) approach together with the wall-adapting local eddy-viscosity (WALE) sub-grid scale (SGS) model is employed for the simulations. Validation results, based on available wind-tunnel measurements, of time-averaged velocity and pollutant concentration for the reference case are reported. Results display that the performance of cross-ventilation in reducing the pollutant concentration enhances as the height to width ratio of the openings increases and the building with horizontally long openings is the most contaminated case. The ventilation performance in the case of vertically long openings is shown to be the most effective one. Furthermore, present findings show that the participation of the turbulent diffusion flux in the passive pollutant transportation becomes smaller as the flow makes progress toward the downstream.

Solutions to mitigate the impact of measurement noise on the air pollution source strength estimation in a multi-zone building

Indoor contaminants jeopardize people’s health and may even cause serious consequences under extreme conditions. Therefore, the prompt and accurate identification of indoor airborne contaminant characteristics is significant for indoor health and safety. In this paper, we used an inverse Markov chain model, combined with the regularization proposed in our previous research, to identify periodic source strength under steady airflow in a multi-zone building. The impact of different measurement noise (0.05%, 0.1%, 0.2%) on the inverse results was investigated. The results showed that the greater the noise, the greater the oscillation of the inverse result. Furthermore, we also investigated the effect of adjusting the calculation time step (5 s, 10 s, 20 s, 30 s) and adding digital filters (Sliding window filter and Butterworth low pass filter) on the inverse source release rate. The results showed that properly increasing the calculation time step can reduce the impact of measurement noise. The root mean square error (RMSE) of the inverse source strength with 0.1% noise decreased from 22.89 under a 5-s time step to 0.9793 under a 30-s time step. It was also found that adding digital filters could reduce the oscillation of the inverse source results, and the performance of the filters also depends on the calculation time steps.

Application of double glazed façades with horizontal and vertical louvers to increase natural air flow in office buildings

The results of previous researches clearly indicate that the main concern in applying double skin façades (DSF) is overheating of the cavity and increasing the cooling energy consumption in warm seasons. The present study intends to consider the excessive heat trapped between two skins of double glazed façades in hot arid climates as a driving force to reinforce the natural airflow across the floors of an office building. To meet this purpose, numerical simulation of airflow and heat transfer inside the cavity of the double glazed façades and the adjacent floors, as well as the effect of different types of solar shading systems in horizontal and vertical modes on the airflow has been investigated using the CFD technique. The results show that the stack effect formed inside the cavity has enough power for air suction from the floors of the building and reinforcement of the natural airflow. The type of shading device has a significant effect on the airflow behavior and the heat transfer rate in the facade. In double skin facades with horizontal louvers, the buoyancy forces inside the cavity are stronger and the ventilation rate in the building floors is higher than the model with vertical louvers. On the other hand, due to the stronger convective flow in the cavity with horizontal louvers, the heat flux on the interior glass is higher than the cavity with vertical louvers and part of the heat inside the cavity is transmitted through the interior skin to the occupied spaces.

Numerical approximation of air flow, temperature distribution and thermal comfort in buildings

Thermal comfort is associated to air flow and temperature distributions in the ventilation system or air conditioning space. In this work, the principal goal is the analyzing of air flow,thermal comfort and the distribution of temperature in the chamber, using a commercial computational fluid dynamics package (ANSYS CFX 15). Calculations are performed in an empty chamber without any human or mechanical activity and the numerical results are compared and validated with measurement points. The comfort level was evaluated using the Air Diffusion PerformanceIndex, ADPI. The numerical results demonstrated that the simulations could precisely predict the temperature and air flow distribution in chamber space. Due the buoyancy effect,the air circulation and air velocity are maintained at high values and the temperature of 19 °C with velocity of 0.15 m.s − 1 gives the best EDT (Effective draft temperature) satisfy ASHRAE 55–210 criteria that V ≤ 0.35 m.s − 1 and Effective draft temperature ranges between -1.7 and 1.1.

CFD investigation of temperature distribution, air flow pattern and thermal comfort in natural ventilation of building using solar chimney

Purpose The purpose of this study is to investigate air flow, temperature distribution and thermal confort in natural ventilation induced by solar chimney for different operating. Design/methodology/approach Numerical simulation is performed using a commercial computational fluid dynamics (CFD) package ANSYS CFX software to understand the effects of air temperature, air velocity and solar heat flux on the performance of the solar chimney and thermal comfort. The comfort level was evaluated using the air diffusion performance index (ADPI) according to ASHRAE (55-210). The flow was investigated at inclination angles 45° solar heat flux 550-750 W/m2 and in a solar chimney of 1.4 m length, 0.6 m width and 0.20 m air gab. Findings The numerical results from the present simulation were first validated with experimental data, which was used for the thermal comfort indexes calculation. The obtained results of the analysis showed that the used numerical technique could accurately predict air flow and temperature distribution in natural ventilated building using solar chimney; the air temperature, air velocity and solar heat flux have a significant impact on thermal comfort; the temperature of 19°C with velocity of 0.15 m.s−1 gives the best effective draft temperature (EDT) satisfy ASHRAE (55-210) criteria that V = 0.35 m.s−1 and EDT range between −1.7 and 1.1. Originality/value In the present paper, air flow, temperature distribution and thermal comfort inside a room equipped with inclined solar chimney were numerically investigated and analyzed. The commercial CFD package (CFX 15) is used. Calculations are carried out in an empty room without any human or mechanical activity and the numerical results are compared with measurement points.