Article
Construction & Building Technology
H. Burak Gunay, Darwish Darwazeh, Scott Shillinglaw, Ian Wilton
Summary: This paper presents a proof-of-concept of an inverse model-based method for the characterization of envelope thermal transmittance and air permeance with historical space heating load data. The method is demonstrated with data from two buildings in Ottawa, Canada. Results show that transient models offer a modest improvement in the thermal transmittance estimates, which are in agreement with those calculated by a physics-based model.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Vitor E. M. Cardoso, M. Lurdes Simoes, Nuno M. M. Ramos, Ricardo M. S. F. Almeida, Manuela Almeida, Ligia Conceicao
Summary: In contrast with structural engineering, the proper assessment and modeling of air change rates in natural ventilation and infiltration require the use of all input variables. Existing modeling methods in infiltration research overlook the intra-hour variability of meteorological variables and assume unchanged neutral atmospheric conditions, which affects the calculated airflows. This study details and quantifies these effects in a representative case study of a single-family dwelling in a Southern European climate.
BUILDING AND ENVIRONMENT
(2022)
Article
Construction & Building Technology
Johannes Brozovsky, Alessandro Nocente, Petra Ruether
Summary: Materials used in the building envelope are exposed to various harsh conditions over extended periods. Understanding these conditions allows for improving testing schemes and extending the durability of building materials.
BUILDING AND ENVIRONMENT
(2023)
Article
Construction & Building Technology
Xi Chen, Miaomiao Qin, Yahui Gao, Yang Liu, Liu Yang
Summary: Understanding the coupling effect of multiple factors on particle deposition above the near-wall heat source is crucial. This study found that temperature, relative humidity, air velocity, and the shape of the near-wall heat sources all influence particle deposition and are further influenced by particle size and location.
INDOOR AND BUILT ENVIRONMENT
(2023)
Article
Construction & Building Technology
Bence Nemeth, Aurel Ujhidy, Judit Toth, Janos Gyenis, Tivadar Feczko
Summary: The experiment compared the PCM-plaster-lined model house and a regular reference model house, finding that the former had less temperature fluctuation but higher energy consumption due to significantly higher average internal temperatures during the test period. However, in the overall house, the PCM-plaster-lined house had a higher heat loss coefficient but a lower heat loss coefficient, indicating that latent heat storage can be economically utilized to maintain a constant internal temperature.
BUILDING AND ENVIRONMENT
(2021)
Article
Thermodynamics
S. Abhinand, Amrita Sharma, Hardik B. Kothadia
Summary: This study investigates the melting phenomena in a Latent Heat Thermal Storage System (LHTSS) using ice as Phase Change Material (PCM) with fins incorporated to improve thermal performance. The PCM-based storage system shows potential in addressing energy supply-demand imbalance. Computed simulations determine the optimal number of fins for improved heat transfer and minimum melting time. The effects of the optimum fin number on different factors such as HTF tube arrangement, diameter, and temperature are evaluated. Comparisons are made using criteria such as liquid fraction, mean temperature, heat transfer rate, and coefficient.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Energy & Fuels
Pedro C. Leal, Diogo M. V. P. Ferreira, Pedro M. S. Carvalho
Summary: This paper proposes a method for estimating accurate network topology and electrical equipment parameters using data from the smart grid. By deriving a linear model of the relationship between the data and the parameters of the admittance matrix, without considering bus voltage angles, and using a regression optimizer to minimize deviations, the model shows accuracy and efficiency in estimating parameters of medium-voltage, three-phase balanced grids, as demonstrated with the IEEE 33 bus system.
Article
Green & Sustainable Science & Technology
Yaxiang Hou, Weidong Wu, Zhenbo Li, Xinyi Yu, Tao Zeng
Summary: This study proposes a novel closed-loop transcritical CO2 air-source heat pump drying system for the drying of medical equipment. The system has a simple structure, higher drying temperature, and an internal heat exchanger (IHX). The experimental results show that the drying air supply temperature (DAST) can reach up to 72.9 degrees C in the designed system. The performance of the system decreases as the DAST increases, with a decrease in the coefficient of heating performance (COPh), coefficient of system performance (COPsys), and specific moisture extraction rate (SMER), while the moisture extraction rate (MER) continuously increases.
Article
Green & Sustainable Science & Technology
Weiqi Wang, Zixuan Zhou, Zhongming Lu
Summary: Room air conditioners (RACs) are high energy-consuming home appliances. Developing a smart solution to evaluate and track the efficiency of RACs is essential. The data-driven framework proposed in this study identifies non-inverter window RACs with low efficiency by analyzing smart meter data and uses XGBoost to predict hourly electricity consumption. The framework separates RACs into low efficiency and normal efficiency categories based on the impact of outdoor temperature on electricity consumption, with promising validation results.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Construction & Building Technology
Di Qin, Jiang Liu, Guoqiang Zhang
Summary: This study proposed a novel coupled system integrating an EAHE and a SAH with PCM to compensate drawbacks of traditional EAHE system. The implementation of PCM effectively stabilized the outlet air temperature and prolonged the working period. Systematic and parametrical analyses showed that critical parameters have significant effects on the thermal and energy performances of the system.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Engineering, Mechanical
Victor Roda-Casanova, Francisco Sanchez-Marin, Raul Martinez-Cuenca
Summary: Heat convection is a significant factor in the cooling process of polymer spur gears running in dry conditions, affecting the gear strength. A numerical heat convection model is proposed in this study, based on a detailed CFD simulation, to investigate heat convection on the external surfaces of the gears. Parametric studies reveal that the relative differences between the results obtained from this model and a representative classical heat convection model can reach up to 125% in terms of heat transfer coefficients. An optimized heat convection model, using empirical equations derived from Newton's law of cooling, is proposed to improve the accuracy of the classical models while reducing the maximum relative differences to 10%.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Thermodynamics
Donglin Hong, Guojun Li, Linyang Wei, Dingyong Li, Pengju Li, Zhi Yi
Summary: The estimation of temporally-spatially varying heat transfer coefficient in air jet impingement is studied based on inverse heat conduction problem. A Self-Scaling Sequential Quasi-Newton Method (SS-SQNM) is developed for solving the inverse problem. Numerical tests show that the SS-SQNM can provide stable and accurate estimates of the heat transfer coefficient with shorter iteration time.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
A. V. S. Oliveira, J. Teixeira, V Schick, D. Marechal, M. Gradeck, S. Denis
Summary: This study evaluates the accuracy and limitations of using a linear model to estimate the boundary heat flux during material cooling. The results show that the linear model performs well for fast cooling conditions, but may lead to errors when dealing with phase transformations and temperature-dependent specific heat.
APPLIED THERMAL ENGINEERING
(2023)
Article
Environmental Sciences
Mary A. Gilliam, Dan van Cura, Graham Garner, Allison Seeley, Ryan Sekol
Summary: This study establishes empirical relationships for estimating the diffusion and solid/air partition coefficients of phthalates in PVC materials. A test chamber and SPME method were used to validate the model, which can be applied to outdoor and manufacturing scenarios.
Article
Construction & Building Technology
Alo Mikola, Anti Hamburg, Kalle Kuusk, Targo Kalamees, Hendrik Voll, Jarek Kurnitski
Summary: This study analyzed the impact of ventilation requirements set in the conditions of a renovation grant on indoor environment through field measurements. The results showed that proper renovation measures can improve indoor air quality and air change rate. Room-based ventilation requirements, heat recovery and preheating measures, as well as inspection of design documentation ensured adequate ventilation and IAQ in the renovation process.
BUILDING AND ENVIRONMENT
(2022)
Article
Construction & Building Technology
Samiran Khorat, Debashish Das, Rupali Khatun, Sk Mohammad Aziz, Prashant Anand, Ansar Khan, Mattheos Santamouris, Dev Niyogi
Summary: Cool roofs can effectively mitigate heatwave-induced excess heat and enhance thermal comfort in urban areas. Implementing cool roofs can significantly improve urban meteorology and thermal comfort, reducing energy flux and heat stress.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Qi Li, Jiayu Chen, Xiaowei Luo
Summary: This study focuses on the vertical wind conditions as a main external factor that limits the energy assessment of high-rise buildings in urban areas. Traditional tools for energy assessment of buildings use a universal vertical wind profile estimation, without taking into account the unique wind speed in each direction induced by the various shapes and configurations of buildings in cities. To address this limitation, the study developed an omnidirectional urban vertical wind speed estimation method using direction-dependent building morphologies and machine learning algorithms.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Xiaojun Luo, Lamine Mahdjoubi
Summary: This paper presents an integrated blockchain and machine learning-based energy management framework for multiple forms of energy allocation and transmission among multiple domestic buildings. Machine learning is used to predict energy generation and consumption patterns, and the proposed framework establishes optimal and automated energy allocation through peer-to-peer energy transactions. The approach contributes to the reduction of greenhouse gas emissions and enhances environmental sustainability.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Ying Yu, Yuanwei Xiao, Jinshuai Chou, Xingyu Wang, Liu Yang
Summary: This study proposes a dual-layer optimization design method to maximize the energy sharing potential, enhance collaborative benefits, and reduce the storage capacity of building clusters. Case studies show that the proposed design significantly improves the performance of building clusters, reduces energy storage capacity, and shortens the payback period.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Felix Langner, Weimin Wang, Moritz Frahm, Veit Hagenmeyer
Summary: This paper compares two main approaches to consider uncertainties in model predictive control (MPC) for buildings: robust and stochastic MPC. The results show that compared to a deterministic MPC, the robust MPC increases the electricity cost while providing complete temperature constraint satisfaction, while the stochastic MPC slightly increases the electricity cost but fulfills the thermal comfort requirements.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Somil Yadav, Caroline Hachem-Vermette
Summary: This study proposes a mathematical model to evaluate the performance of a Double Skin Facade (DSF) system and its impact on indoor conditions. The model considers various design parameters and analyzes their effects on the system's electrical output and room temperature.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Ruijun Chen, Holly Samuelson, Yukai Zou, Xianghan Zheng, Yifan Cao
Summary: This research introduces an innovative resilient design framework that optimizes building performance by considering a holistic life cycle perspective and accounting for climate projection uncertainties. The study finds that future climate scenarios significantly impact building life cycle performance, with wall U-value, windows U-value, and wall density being major factors. By using ensemble learning and optimization algorithms, predictions for carbon emissions, cost, and indoor discomfort hours can be made, and the best resilient design scheme can be selected. Applying this framework leads to significant improvements in building life cycle performance.
ENERGY AND BUILDINGS
(2024)