Abstract According to IPCC (2014), the global mean temperature is expected to increase from 1.4 °C to 5.8 °C by 2100. The implications will be particularly significant in urban areas as indoor and outdoor comfort levels will be disrupted, leading to significant health impacts. One of the expected impacts is indoor overheating, as it has been identified as one of the major causes of thermal discomfort

To achieve the energy and emissions reduction goals for the building sector, actions are needed to improve energy efficiency and occupants’ wellbeing. To increase the uptake of smart technologies and the awareness upon their benefits, in line with the smart building revolution that is starting, the EPBD recast introduced the Smart Readiness Indicator (SRI) as a tool to evaluate the capability of buildings

This work illustrates the results achieved by ongoing collaboration between the Uffizi Gallery and the University of Florence. This collaboration has focused on the New Uffizi Project and sought to evaluate the energy consumption of the HVAC systems of the Vasari Corridor by applying the typical tools and methods for the Building Energy Model (BEM) of existing buildings. In order to perform a dynamic

Abstract Modelling the change in atmospheric pressure as a function of altitude is of great interest in many fields of study, research and variety of practical applications reaching beyond aviation. Similar to the human performance being adversely impacted by change in elevation the same holds true for most equipment also relying on air to exchange energy and take in oxygen. The standard model atmosphere

Abstract This study aims to investigate the effect of demand response (DR) on power and energy flexibilities with three types of district heated buildings (apartment building, cultural center, and office building) in Finland and Germany. The rule-based control algorithm was applied for the DR control with two country-specific dynamic district heating (DH) prices, the more fluctuated Finnish synthetic

Abstract This paper systematically examines the in-use energy and carbon performance of a large case study housing development in England, designed to be net true zero carbon. Remote monitoring during a one-year period was used to gather high-frequency data on dwelling heat use, grid electricity use, solar PV electricity generation and export and community heating system performance. Based on data

Abstract In 2021, COVID-19 has been widely spread worldwide. Few studies focused on infection risk in the different confined spaces on university campuses. However, obtaining the quanta value of SARS-CoV-2 using the conventional method is not identical. Therefore, in our study, the estimation method of the quanta value was improved via statistically analyzing the viral load of the infectors and fitting

Following our previous study, which indicated that several occupant-related assumptions in the National Building Code (NBC) of Canada are different from findings in recent measurement-based studies, this study aims to: i) quantify the direct energy impact associated with discrepancies between the current code’s occupant-related assumptions and those obtained from recent measurement-based studies and

In order to ensure energy saving and reliable operation for the actual multi-chiller systems, this paper proposes a novel chiller loading strategy that combines the operation data and domain knowledge. The operation data is used to establish the near-optimal performance map which can guide the optimization of chiller loading. The domain knowledge is used to formulate rules to keep the operation reliability

The compliance with the indoor environmental quality (IEQ) requirements should be considered when designing retrofit actions for the refurbishment of existing buildings. The research is aimed to reduce the imbalance between the visual and thermal domains through the improvement of different design parameters in compliance with the nearly zero-energy building (nZEB) requirements. The article proposes

This paper investigates the dynamic behavior of dual vapor compression Refrigeration (VCR) chillers, considering nine ecofriendly refrigerants such as R134a, R32, R1234yf, R1234ze(E), R717, R600, R600a, R290, R410a and compared to R22. Disturbances are introduced to the secondary loop of the VCR as sudden and ramp increases of the inlet cooling and chilled water temperatures and their impact on the

This study proposes the use of hydrofluoroolefins and organic absorbents mixtures as a working fluid pair in a single-effect absorption refrigeration system. In the refrigeration cycle, the 2,3,3,3-tetrafluoropropylene (R1234yf) is used as a refrigerant, and the triethylene glycol dimethyl ether (DMETrEG) and N-methyl-2-pyrrolidone (NMP) are used as absorbents. The working fluid’s thermophysical properties

In this study, volatile organic compounds (VOCs) were measured from 47 hospital rooms to determine the most suitable sampling location for VOCs indoors. Another goal was to find out the most predominant VOCs and their emission per floor area in a hospital environment. Three samples were taken from each room simultaneously: one from the center of the room, one from the floor near the wall, and one from

The effects of two window states (closed or open) on the bedroom environment and on sleep quality were investigated. Twenty-seven subjects (14 males and 13 females, 20–33 years old) without sleep disorders and chronic diseases participated. The subjects slept for two consecutive nights with windows open and two consecutive nights with windows closed in four dormitory rooms adapted for the purpose of

Abstract This study was conducted to investigate the flow and heat transfer characteristics of a flat plate located between two symmetrical cylinders. Flow visualization experiments were conducted based on the open-loop fluid test bench to verify the accuracy of numerical simulation. The effect of non-dimensional vertical gap space (C/D) between the cylinder and the plate ranged from 0.1 to 0.8 were

Abstract Strong evidence exists indicating that aerosol transmission of the novel coronavirus SARS-CoV-2 is a significant transmission modality. We experimentally evaluated the impact of ventilation on aerosol dynamics and distribution along with the effective filtration efficiency (EFE) of four different mask types, with and without mask fitters, in a classroom setting. These were used to estimate

In this study, the energy flexibility potential of a residential building with an air-based building integrated photovoltaic thermal (BIPV/T) system coupled to an air-source heat pump was investigated. A residential archetype row house, typical of Montreal, was simulated in TRNSYS. The objective of the study was to investigate how rule-based controls and a water-based sensible thermal energy storage

The adsorbent material has an important role in the improvement of desiccant cooling system performance. Super Desiccant Polymer (SDP) is chosen in this work as a sophisticated desiccant material characterized by excellent adsorption capacity and durability. The mathematical correlations of adsorption isotherm on SDP surface, adsorption heat and water diffusivity coefficient are used to model the SDP

Urban building energy models (UBEM) are driving sustainable design and operations of cities by combining urban datasets with energy simulations. UBEMs are developed from a range of inputs on the spatial and semantic details of the buildings, and the systems affecting their energy performance. Large geographical scales with finer spatio-temporal details increase the challenges of data processing for

The persistence of energy savings due to the implementation of Existing-Building Commissioning (EBCx) is an important measure of the benefit of EBCx. This study analyzes the persistence of energy savings achieved from the implementation EBCx in nine buildings from 1997 to 2018. Each is served by a central utility plant (CUP) with metered chilled water (CHW) and heating hot water (HHW). EBCx was initially

Computerized maintenance management systems (CMMSs) of large commercial and institutional buildings archive work order logs. These logs contain invaluable operational performance indices pertaining to occupants and building systems. However, there are barriers to extract and visualize meaningful metrics from CMMSs. This study proposes a three-part framework to facilitate this process. The first part

The presence of an air-space within a building envelope is known to have a varying contribution to the overall thermal performance of the wall assembly due to the combined effect of convection and radiation in the air cavity. In particular, the thermal resistance of a ventilated air-space can vary significantly depending on multiple environmental and thermo-physical parameters. Although the thermal

The abundance of heat-trapping asphalt and concrete, smog, and heat emitted from buildings and vehicles is one of the major reasons for the prevailing high temperature, air and noise pollution in cities. Incorporation of green wall in buildings is considered to be an effective method to reduce temperature and mitigate environmental pollution. This study investigated and compared the performance of

This paper presents a numerical simulation of a ventilated roof based on a novel plastic support especially designed to reduce the solar heat gains by improving the airflow distribution as compared to a traditional one. In order to evaluate the benefits of the new configuration, a 3 D numerical model was developed allowing for a deep understanding of the airflow distribution inside the ventilated roof

In this study a test procedure for determining capture efficiency (CE) of domestic range hoods, namely ASTM-E3087.18, was used to investigate how changing the exhaust orientation of residential range hoods influences CE. Previous studies on residential range hood CE only utilized vertical discharge orientation and do not strictly adhere to ASTM-E3087.18. Furthermore, many range hoods are installed

Operable windows have become desirable design features of modern mechanically ventilated office buildings in North America. While they improve perceived control and adaptive comfort, their inappropriate use poses risks associated with increased heating and cooling energy use. Therefore, the sequence of operations for terminal devices serving zones with operable windows should be designed in recognition

Abstract The change over time of energy performance of large chillers used in commercial and institutional buildings is seldom presented in the literature. Most studies are based on measurements of small capacities of residential air-conditioners and heat pumps. Authors found in the literature only three papers on this topic. This paper presents the evidence-based assessment of long-term performance

Abstract While occupancy-based control and other demand management control strategies have demonstrated potential, little is known about how these changes in heating, ventilation, and air-conditioning (HVAC) control impacts occupants’ perception of the thermal conditions in their home. In this paper, occupants’ thermal comfort perceptions and use of thermostat overrides under three different control

The purpose of the article is to study the impact of buildings balconies on the energy consumption and indoor parameters. Using both experimental and numerical approach multiple insights were found. The first part is focused on the analysis of 75 block of flats and the influence of closing the balconies on the energy efficiency. It was found out that most of the apartment’s owners have individually

ABSTRACT A novel Heat Pump-Photovoltaic/Thermal (HP-PV/T) integrated system designed to meet space heating and cooling, electricity generation, domestic hot water production efficiently is a proposed experimental research study. The heat pump running with two evaporators and two condensers operating as air-water and air-air in the HP-PV/T integrated system has been specifically manufactured. This multi-purpose

Abstract In this research work, results on optimization of parameters related to energy consumption for indoor climate control of a building enclosure are discussed. The analysis is carried out for a building unit maintained at comfort level using Mitsubishi 1.5 ton of refrigeration split air conditioner. A mathematical model based on energy balance and experimental trials were used to compute energy

Theoretical and experimental studies are carried out on a transcritical CO2 based air-conditioning unit. Two configurations– a system with single-stage expansion (SSE) and a system with two-stage expansion (TSE) have been considered. Detailed numerical models have been developed for both configurations. Results obtained from numerical simulations are compared with experimental results. The performance

The displacer-type pulse tube refrigerator is a kind of Stirling-type pulse tube refrigerator with work recovery. It uses a displacer as a phase shifter and has the advantages of high efficiency and compact structure. One-dimensional numerical simulation of the displacer-type pulse tube refrigerator is performed, and the accuracy of the simulation is experimentally verified. The parametric analyses

Abstract This study provides a review of the current state of knowledge, gaps, and potential value in research on the prevalence of faults in commercial buildings. Two separate efforts were made in this study: (1) we performed a literature review to determine the extent of currently available fault prevalence data for heating, ventilation, and air-conditioning (HVAC) systems, and (2) we conducted dozens

Abstract Domestic hot water production is responsible for a significant part of domestic energy consumption; instantaneous gas heating devices are widely used because they don’t require reservoirs, therefore have a competitive use/consumption ratio compared to other technologies. However, users' perception of comfort is severely affected by sudden changes in temperature outside the desired temperature

This study presents the energy savings impact of the Continuous Commissioning® (CC®) version of the Existing Building Commissioning (EBCx) process in 197 projects (592 buildings) since the inception of the process in the early 1990s. These are the results of a comprehensive evaluation of the impact of EBCx projects. The evaluation of the impact of EBCx by building type included 316 education buildings

Shallow bore ground heat exchangers have been investigated in recent years because they have the potential to reduce the initial cost of the ground source heat pump system. Correctly modeling the transient heat transfer between the ground heat exchanger and the surrounding soil is essential for predicting a ground heat exchanger's performance. Simplification of the soil model could increase computation

This study develops an add-on local sweating simulation system to upgrade existing dry thermal manikins to local and sweating thermal manikins. The performance of this system was studied using a dry thermal manikin resembling a human lying on a bed with a ventilated mattress. The system comprises water-repellent porous hollow tubes to discharge water onto a diffusive fabric, as well as a motorized

The effect of thermal discomfort on human well-being and performance was studied in the field office, and an attempt was made to elucidate its psychological mechanism. Thirty participants were recruited to perform subjective evaluations and performance tests under 5 different conditions (25 °C, 27 °C, 29 °C, 31 °C, 33 °C). During the experiment, the air temperature was considered as an independent

Abstract In turbulent flows as in HVAC applications, the fluctuation of air speed can affect the sensation of thermal comfort. This study is a part of a larger experimental and numerical campaign intended to evaluate the influence of the turbulence intensity at the inlet of air distribution systems on the local draft sensation and thermal discomfort for different ventilation cases using numerical simulations

Residential sector is considered one of the largest consumers of primary energy in the world. The main part of total energy consumption in buildings refers to heating. The study presents a thermodynamic sustainability assessment of different energy sources for residential building heating. The paper presents universal methodology, which can be applied to energy and exergy analysis for all types of

The assessment of thermal comfort for patients admitted in hospitals is a mandatory prerequisite meant to ensure the improved wellbeing and support of healing. Our study focused on postpartum women, a particular category of patients, given that they are healthy individuals admitted in hospitals for a physiologic process. We investigated the indoor thermal comfort of 61 early term postpartum breastfeeding

This study investigates the influence of glazing characteristics and shading device configuration on energy use and cost, daylighting performance and visual comfort. A typical patient room from a hospital design in Belgium is used as a baseline scenario and different window design alternatives are explored through parametric modeling. Based on the comparative analysis, the article discusses potential

Abstract Thermal comfort evaluation for vehicle occupants is very complicated due to the transient nature and non-uniformity of the vehicle interior. The thermal sensation of an automobile occupant is affected by the surrounding environment. Furthermore, the existing standard was developed for steady state and controlled conditions and it utilizes three evaluation indices, some of which are not adapted

The film wetted area is a significant factor affecting the heat and mass transfer of liquid desiccant. In this article, a mathematical model with wetness coefficient of cross-flow energy recovered indirect evaporative cooling (ERIEC)-assisted liquid desiccant dehumidifier (LDD) based on a finite-element method was developed to predict the effect of wetness coefficient on the plate heat exchanger (PHE)

(2021). Professor Raymond Cohen 1923–2020. Science and Technology for the Built Environment: Vol. 27, No. 4, pp. 391-392.

This paper presents the ASHRAE transport properties model for moist air as a "real-gas mixture" employing a modification of the mixing model of Vesovic and Wakeham. It uses the latest research from the International Association for the Properties of Water and Steam (IAPWS), the International Union of Pure and Applied Chemistry (IUPAC), and the National Institute of Standards and Technology (NIST).

The outdoor seasonal weather conditions can influence the insulation performance of extensive green roof. In addition, the thermal behavior of extensive green roof can be affected by the thickness of its layers including substrate and drainage layer. On the other hand, the replacement of polyethylene modular panel with porous aggregates as drainage layer can affect the water retention capacity of green

An improvement of a formerly proposed CFD-based methodology (base model) for the estimation of water evaporation rate in swimming pools is presented here. This base model achieved satisfactorily on average (10% of relative error) under mixed and natural convection, but it deviated from the experimental measurements significantly (up to 45%) for conditions dominated by forced convection. The enhancement

The construction industry is responsible for 36% of the European Union's greenhouse gas emissions. The main goal of the EU in the last decade has been to boost energy efficiency and expand the use of renewable energy in buildings. Ground-to-air heat exchangers may be a solution to reduce the use of primary energy in buildings from nonrenewable sources. The study in this paper deals with an evaluation

Direct ground cooling systems (DGCS) can provide comfort cooling to buildings without the use of any refrigeration-based cooling methods. DGCS is an emerging technology, commonly used for new office buildings in cold climates. This study aims to evaluate the energy-saving possibilities of a DGCS compared to a conventional chiller system for an existing office building. A typical Swedish office building

Potential energy savings achievable by using isothermal dehumidification instead of conventional air conditioning systems are modeled on a technology-agnostic basis. First, we use simple thermodynamics to model potential device-level energy savings by dehumidifying isothermally instead of by sub-dew-point cooling. A model for dehumidification demand in a prototypical house is then developed, and the

Hydronic coils are often exposed to non-uniform air velocities due to a series of factors, including tight spacing between a fan and a coil, flow area contraction and expansion, existence of obstructions, abrupt change in airflow direction, or the combination of above factors. Although studies showed non-uniform air velocities could cause performance degradation for direct expansion (DX) cooling coils

Refrigerators are the most energy demanding household devices since they are working 7/24. Improving insulation material is crucial for reducing this demand. One of the promising ways to improve insulation materials is to develop better-blowing agents. In this study, the effects of Liquid Blowing Agent (LBA) and Pentane Blowing Agent (PBA) on whole refrigerator insulation were investigated by experimental

Chillers play essential roles in the heating, ventilation and air conditioning (HVAC) systems to ensure the required thermal comfort. To reduce the operational risk such as faulty operation or energy waste, it’s essential to develop the robust and effective fault detection and diagnosis (FDD) strategy for the chillers. This paper presents a novel hybrid reference model called multi-region XGBoost model

Chillers play essential roles in the heating, ventilation and air conditioning (HVAC) systems to ensure the required thermal comfort. To reduce the operational risk such as faulty operation or energy waste, it’s essential to develop the robust and effective fault detection and diagnosis (FDD) strategy for the chillers. This paper presents a novel hybrid reference model called multi-region XGBoost model

Abstract The film wetted area is a significant factor affecting the heat and mass transfer of liquid desiccant. In this paper, a mathematical model with wetness coefficient of cross-flow energy recovered indirect evaporative cooling (ERIEC) assisted liquid desiccant dehumidifier (LDD) based on finite element method was developed to predict the effect of wetness coefficient on the plate heat exchanger

In this work, the effect of flow circuitry on the performance of a household freezer with a tube-on-sheet evaporator is investigated. The evaporator used in the freezer is a tube-on-sheet type where the tubes are bent and attached underneath the shelves, as in the serpentine heat exchanger. The evaporator is composed of six shelves that are located inside the cabin with a particular distance between

In the last few years, a significant amount of research has focused on learning and modeling personalized thermal preferences to satisfy individuals in buildings. However, there is a disconnection between personal comfort studies and building thermal control research. The objective of this article is to review research studies that integrate personalized thermal preferences into building control systems

A transient multipole method for short-term simulations of ground heat exchangers (GHEs) is presented. The two-dimensional unsteady heat equation over a GHE cross section is separated into two problems: (i) a transient heat equation with homogeneous boundary conditions, and (ii) a steady-state heat equation with nonhomogeneous boundary conditions. An eigenfunction expansion is proposed for the solution