Abstract Building performance optimization is a powerful technique that assists designers in identifying optimal design solutions. However, occupant-related uncertainty is considered a major challenge that can influence the credibility of the selected optimal design. This paper proposes an occupant-centric method for window and shading design optimization in office buildings that assists designers

ABSTRACT The goal of this paper is to quantify the impact of weather-induced and altitude-induced barometric pressure variations on the cooling capacity measurement of hydronic coils in room fan coil units. Based on an AHRI-certified coil simulation model and the Monte Carlo sampling method, capacity measurement data were simulated for three hydronic cooling coils at a fixed testing condition with

(2020). Correction. Science and Technology for the Built Environment. Ahead of Print.

Abstract Nowadays with the development of science, many new technologies are being introduced to the fabric membrane material fields. Membrane structures have been widely used in industrial storage buildings to reduce the dust pollution from open storage depots. But the thermal environment of these buildings is poor due to its light weight and low thermal resistance. It is worth exploring appropriate

(2020). IAQVEC: New developments in HVAC design and operation. Science and Technology for the Built Environment: Vol. 26, Papers from IAQVEC 2019, pp. 1351-1351.

Decentralized mechanical ventilation systems had a sustainable growth in the past ten years in order to guarantee air exchange in highly airtight renovated residential buildings. Smart control strategies could provide a solution to the tradeoff between energy efficiency, hygrothermal comfort and indoor air quality. In this paper, a novel fuzzy demand controlled ventilation strategy is proposed, using

In late 2019, ASHRAE hosted the Great Energy Predictor III (GEPIII) machine learning competition on the Kaggle platform. This launch marked the third energy prediction competition from ASHRAE and the first since the mid-1990s. In this updated version, the competitors were provided with over 20 million points of training data from 2,380 energy meters collected for 1,448 buildings from 16 sources. This

In a building-integrated agriculture (BIA) space, peak loads must be estimated to size HVAC equipment in order to maintain indoor air conditions that enhance crop growth. However, the estimation of the rates of heat gain/loss induced by the crops and their impact on heating and cooling loads have only been sparsely addressed. The present study proposes a workflow to estimate the impact of crops on

This paper aims at investigating the performance of some passive techniques integrated to a house in six climates ranging from Cold climate to Desert one. First of all, a case study of a house, located in Marrakech (Hot Semi-Arid climate), is monitored and a TRNSYS-based numerical model is constructed and calibrated using the resulting experimental measurements. Afterwards, thermal behavior as well

(2020). Correction. Science and Technology for the Built Environment: Vol. 26, Papers from IAQVEC 2019, pp. 1509-1515.

Abstract CO2-based Demand-Controlled Ventilation (DCV) has been proved to be energy-efficient by altering ventilation rates according to surrogated indications of CO2 levels in single- and multiple-zone single-path VAV systems. However, DCV for multiple zone VAV systems with multiple recirculation paths is still untapped. The multiple-zone VAV systems with series and parallel Fan-Powered Terminal Units

Abstract In this study a test procedure for determining capture efficiency (CE) of wall-mounted range hoods, namely ASTM-E3087.18, was used to investigate how the temperature of the simulated cook-top influences CE. ASTM-E3087.18 was initially released in 2017 and revised within one year to modify the temperature requirements of the cook-top from 200?C to 160?C; however, there is no evidence of a detailed

To respond to new energy efficiency standards and environmentally friendly policies in hot climate regions, it is necessary to develop high-efficiency air conditioners. The environmentally friendly and favourable thermo-physical properties of R290 and the high efficiency of rotary compressors have led to the proposal of R290 rotary compressors for use in split-room air conditioners in hot climate regions

(2020). Correction. Science and Technology for the Built Environment. Ahead of Print.

Monitoring performance of heating, ventilation and air-conditioning (HVAC) during building operation enables to evaluate the appropriateness of the system’s design. Such insights can help to reduce energy consumption while ensuring satisfying indoor conditions in the monitored building. Additionally, such insight can help to improve future HVAC design. The aim of this paper is to present a case study

Trains are an important means of transportation for people to travel. The train's soft sleeper compartment space is relatively small, the density of people is relatively large. Therefore, improving the thermal comfort and air quality of the compartment is of great significance for ensuring a healthy travel environment. To analyze the appropriate mode of conditioned air supply in the train soft sleeper

Wet cooling towers are thermally high efficient and cost-effective industrial cooling units, which are used in factories, energy plants and in the heating, ventilating and air conditioning (HVAC) market. The working principle of the cooling towers is based on the cooling of the hot process water with cold atmospheric air via cooling fills and water distribution systems. The aim of this study is to

Many studies have been conducted to assess the effects of indoor air quality (IAQ) on human health. However, there is still a lack of studies available about the adverse health effects on children’s respiratory health at Child Care Centres (CCC). The aim of this paper was to investigate the risk factors for respiratory symptoms and identify the root cause of IAQ problems at CCCs in Malaysia. The Modified

This work aims to develop two main ideas: first, the use of the artificial neural network (ANN) approach to predict the moisture removal rate (MRR) and the dehumidifier effectiveness (ɛ) of a counter-flow liquid desiccant dehumidifier using calcium chloride as an absorption solution. Second, the Garson method is used to identify the most important working parameters influencing the performance of the

Operating room ventilation is quite important to protect patients from infection risk inside a surgical field. The laminar flow units (LAF) used in these applications contribute to removal of pathogen particles from the operation area by creating a protection zone on the surgical field. In this study, effect of LAF diffuse size on airflow and particle distribution in an operating room is investigated

Airflow measurement is essential to efficiently operate air handling units (AHUs) in commercial buildings. Due to the space and cost limitations for physical meters, many virtual airflow meters have been developed for induction motor driven fan systems. On the other hand, electronically commutated motor (ECM) fans have been widely applied in AHUs. However, the applicability of virtual airflow meters

This paper describes a numerical model that was developed to predict flow and pressure distribution in three multi-branch air duct systems as a function of upstream static gauge pressure. The duct systems were comprised of a combination of wire-wound flexible ducts and rigid sheet metal ducts. The model used the Darcy equation and the concept of the local loss coefficient, in conjunction with the continuity

Owing to design and operation limitations, most multi-zone variable air volume (VAV) systems in existing buildings still follow traditional techniques for ventilation. In recent ventilation research, most studies focused on comparing a traditional strategy with a superior one, and the comparison studies among traditional strategies are relatively rare. In this paper, four traditional outdoor airflow

The design of windows can provide the proper lighting of the interior and create comfortable conditions to increase the efficiency of the building. Furthermore, in designing building façade articulation, it is important to consider the projection and indentation, therein. This study aimed to evaluate the optimum parameters of the window by measuring energy consumption and daylight quality in residential

(2020). Toward a user-centered built environment. Science and Technology for the Built Environment: Vol. 26, No. 9, pp. 1163-1164.

Part-load performance models for fans driven by electronically commutated motors in fan-powered terminal units were developed based on the analysis of data from 36 series and parallel units provided by four manufacturers. Fan motors ranged from 0.33 to 1 hp (249 to 746 W) and maximum external static pressures from 0.5 to 0.75 in. w.g. (125 to 188 Pa). Part-load performance was estimated from the intersection

This article investigates the in-tube, superheated, saturated, and subcooled condensation of zeotropic refrigerant mixture R454C. R454C is proposed to replace R404A for commercial refrigeration applications. Quasi-local heat transfer coefficients were measured in a 4.7 mm horizontal tube at mass fluxes ranging from 100 to 500 kg m−2 s−1 at three different saturation conditions (40, 50, and 50 °C).

In order to investigate the impact of water quality on fouling process of enhanced tubes, two continuous fouling tests on eight enhanced tubes (with different internal and external tube geometries) and one plain tube (with a plain inside surface and an enhanced outside surface) were carried out in duration of 98 days, using cooling water with medium and low fouling potential respectively at a water

Combined district heating (DH) systems have at least one base load heat plant and several peak-shaving heat sources, which can be installed in the primary network or in the heating substations. This article studies the combined DH system with peak-shaving gas-fired boilers in heating substations, where the peak boilers can be connected to the heat exchangers in series or parallel mode. We analyze the

An experimental test rig is utilized to measure the effects of the flow configuration and particularly the rib geometry, on the thermal performances of solar air heaters. Since the heat transfer rate within the entry length is relatively high, the implementation of the ribs needs to be justified. Computational fluid dynamics simulations are also conducted to support the experiments and to provide detailed

Accurate performance measurements of equipment in the laboratory requires air mixing to reduce temperature and humidity measurement error. The National Bureau of Standards (NBS), now known as National Institute of Standards and Technology (NIST) conducted in-depth experimental research on the static air mixing devices in the late 1960s, which remains the most comprehensive work in this area. Today

Public attention has been drawn to the commercial restaurant cooking emission since it can cause health and hygiene risks, reduction of the efficiency of the ventilation system, and even fire accidents. The attempt of including the Ultraviolet-C (UVC) lamps with Type I hood has the potential to reduce the grease deposition on the ductwork and pollution in the exhaust by oxidizing the emissions. A method

Thermal adaptation plays crucial role in energy efficient operation of buildings without compromising with human thermal comfort. Elevated air velocity is commonly desired to restore comfort requirements at higher temperatures especially in NV and MM buildings located in tropical countries like India. This article is the systematic field study comprising a total of 4872 responses (1874 from NV buildings

Programmable thermostats with frequent schedule overrides (i.e., “holds”) are widely assumed to be detrimental to potential energy savings. We explored whether this assumption generalized to a population of smart thermostats using a longitudinal dataset of 20,000 devices from a single manufacturer. We observed a majority of devices were infrequently overridden, most often to less energy-efficient setpoints;

To improve the ventilation and air-conditioning energy efficiency of buildings in hot and dry climates, this paper proposed and experimentally investigated an indirect flash evaporative cooling (IFEC) technology combining plate heat exchanger with ultrasonic atomizer. Compared with traditional indirect evaporative cooling (IEC) technology, working air is humidified to be over-saturated by ultrasonic

Extremum Seeking Control (ESC) strategies are a class of model-free real-time optimization techniques. Because conventional ESC (CON-ESC) based on the dither-demodulation has relatively slow convergence, various alternative forms of ESC have been proposed to improve the transient performance. The purpose of this study is to compare a recently proposed input-output correlation ESC (IOC-ESC) strategy

(2020). Integrating IAQ control strategies to reduce the risk of asymptomatic SARS CoV-2 infections in classrooms and open plan offices. Science and Technology for the Built Environment: Vol. 26, No. 8, pp. 1013-1018.

(2020). Investigating the impact of filters on long-term particle concentration measurements in residences (RP-1649) Science and Technology for the Built Environment: Vol. 26, No. 8, pp. 1037-1047.

It is widely acknowledged that demand response must play an increasingly important role in future electricity markets. This is as much due to increasing demand for air-conditioning as it is due to the changing sources of generation. In the National Electricity Market (NEM) in Australia, for just 3% of the year demand increases by 20%, or the equivalent of the generation from the two largest coal fired

This paper presents a near-optimal control algorithm for minimizing energy costs in hybrid cooling plants in response to cooling loads. The approach is based upon an approximate solution to the partial differential equations involved in minimizing the cost of energy consumed by the plant with respect to two control variables: cooling tower airflow and condenser water flow. The parameters of the algorithm

Building automation system uses several networks of sensors for continuous monitoring of building control systems for energy-efficient operation. Physical sensors are costly and need frequent calibration. The accurate measurement of supply air temperature from the air handling units (AHUs) has an important effect on the control of cooling coil, supply air temperature and supply airflow rate delivered

Ventilation systems are necessary to ensure a good indoor air quality, especially in buildings characterized by high energy performance. An all-air system could be more flexible than radiant systems that need to be combined with other systems to provide fresh air and control latent loads. In this work, a multi-zone all-air system has been compared with a radiant floor integrated with mechanical controlled

With the continuous promotion of urbanization, numerous large-scale public buildings appear in cities. Concerning the characteristics of large floor-area and high personnel-density, creating a thermally comfortable environment is significant to large-scale buildings. However, uneven thermal environment is usually detected in large-scale space, which shows that some areas are overcooled while some lack-cooling

Growing number of household refrigerators and freezers also increase the overall energy consumption and number of household refrigerators have grown nearly 3% per year. On the other hand, investigations showed that household refrigerators have a significant technical energy saving potential of up to 30-40%. In this study, a single-phase natural circulation loop is considered as a suction line heat

Systematic and random errors for working sensors in building systems can seriously affect the operation performance and have a significant negative impact on energy efficiency and indoor comfort. However, the traditional method for sensor calibration is very time-consuming and labor-intensive. Therefore, a virtual in-situ calibration (VIC) method was proposed based on Bayesian inference that can simultaneously

Motor-driven fan systems in air handling units (AHUs) account for 15.9% of the electricity consumption in commercial buildings. Currently electronically commutated motors (ECMs) have seen increasing applications to replace induction motors for energy savings. While efficiency models for motor-driven fan systems are essential for building energy management, there is no valid efficiency model for ECM

In this study, R404A and R452A refrigerants used in refrigeration systems were compared experimentally. The energy performance of the system was investigated for widely used evaporation temperatures (−5, 0, +5 °C) and condenser temperatures (25, 35, 45 °C). It was seen that COP was higher but power consumption of system was lower using R452A as a substitute for R404A. When R452A was used, COP was improved

With an equal mass, nanoparticles (NP) have a higher toxicity than particles with the same chemical composition but with larger surface area. However, the toxicological knowledge concerning NP is still insufficient to establish limit values of exposure. To seek the lowest exposure level, filtration is a simple and effective way to capture particles, including NP. According to ANSI/ASHRAE 52.2 standard

The air-source heat pump (ASHP) is a popular system that does not see much use in cold-climates despite its high potential in low carbon footprint. This study was designed to evaluate the techno-economic feasibility of its application to single-detached homes in Canada. First, a set of support vector regression (SVR) models was developed by a housing database for prediction of the exposed surface areas

In current design practice, chillers and pumps are often oversized due to conservative consideration of uncertainties using safety factors to avoid the risk of undersizing, which often results in significant energy waste in operation. In recent years, probabilistic optimal design methods have been proposed for the components of cooling systems, enabling risk-based decision-making rather than sizing

A novel dataset based on satellite observations of aircraft positions was utilized to estimate normal accelerations of commercial aircraft during climb and descent legs. Further, these accelerations are used to simulate the effects on exposure to expiratory airborne contaminant inside commercial aircraft cabins. Compared to previous studies, which reported exposures more than twice due to high aircraft

In this study, a detailed modeling applicable for membrane dehumidifying system is proposed. This system contains a membrane module, 2-stage vacuum pumps, a condenser, and a regulating valve. The proposed model does not need any prior setting of the vacuum level of the permeate side, and the predictive results are in line with the benchmark. It is found that the COP (coefficient of performance) is

Energy can be recovered from building exhaust via water vapor transport and heat transfer across gas permeation membranes, thereby reducing latent and sensible loads during both heating and cooling seasons. The process known as membrane-based energy recovery ventilation (ERV) has been commercialized by several HVAC manufacturers, but so far has mostly been offered in flat sheet membrane configurations

Utilization of PCM-to-Air Heat Exchangers (PAHXs) in building free cooling applications has been reporting the insufficient cooling charging energy during the PCM solidification, which affects the overall system performance. This study reports the improvements in the cooling potential of the PAHX considering the climatic characteristics of the hot desert climate by taking the advantage of thermal radiation

A cooling tower (CT) model was built based on physical thermodynamics and heat and mass transfer principles using the effectiveness-NTU method for heat exchanger performance. The focus of the model was to use non-intrusive measurements and predict the exiting water temperature from the cooling tower given certain inputs. Compared with the existing models, the new model has two main advantages: (1)

By coupling algorithmic optimization with parametric modeling and performance simulation, the building design process becomes a series of informed decision-making. Algorithmic optimization helps architects find high-performance design choices which balance complicated tradeoffs among various performance objectives. Although algorithmic-optimization aided design is more competent than the traditional

This paper assesses the current level of the application of passive/natural and daylighting systems in the US by architects and engineers. Although an extensive list of publications about passive/natural and daylighting systems exists, there are very few studies addressing the degree of applying these systems in practice. This paper, through the application of a survey methodology, evaluates the level

In this study, the combined power and refrigeration cycles driven by low-grade thermal energy is evaluated. An organic Rankine cycle (ORC) and a vapor compression refrigeration cycle (VCRC) are linked for both power generation and cooling. Three different combined cycle configurations are considered in the analyses. These are a basic ORC-VCRC, a dual-fluid basic ORC-VCRC, and a dual-fluid ORC-VCRC

By coupling algorithmic optimization with parametric modelling and performance simulation, the building design process becomes a series of informed decision-making. Algorithmic optimization helps architects find high-performance design choices which balance complicated trade-offs among various performance objectives. Although algorithmic-optimization aided design is more competent than the traditional

In this study, three different diffusers (V profile perforated, flat anemostat type and pyramid anemostat type) have been designed in order to spread the air in shorter distance in empty cells used in central air handling units. The pressure drop caused by these diffusers has been investigated experimentally. The diffusers are mounted at the center of the fan outlet section, up or down the center (the