scholarly journals Energy Modelling and Calibration of Building Simulations: A Case Study of a Domestic Building with Natural Ventilation

Energies ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 3360 ◽  
Author(s):  
Carolina Aparicio-Fernández ◽  
José-Luis Vivancos ◽  
Paula Cosar-Jorda ◽  
Richard A. Buswell
Keyword(s):  
Energy Demand ◽  
Natural Ventilation ◽  
Transient Flow ◽  
Residential Buildings ◽  
Infiltration Rate ◽  
Energy Performance ◽  
Performance Modelling ◽  
Change Rate ◽  
Air Change Rate

In this paper, the building energy performance modelling tools TRNSYS (TRaNsient SYstem Simulation program) and TRNFlow (TRaNsient Flow) have been used to obtain the energy demand of a domestic building that includes the air infiltration rate and the effect of natural ventilation by using window operation data. An initial model has been fitted to monitoring data from the case study, building over a period when there were no heat gains in the building in order to obtain the building infiltration air change rate. After this calibration, a constant air-change rate model was established alongside two further models developed in the calibration process. Air change rate has been explored in order to determine air infiltrations caused by natural ventilation due to windows being opened. These results were compared to estimates gained through a previously published method and were found to be in good agreement. The main conclusion from the work was that the modelling ventilation rate in naturally ventilated residential buildings using TRNSYS and TRNSFlow can improve the simulation-based energy assessment.

scholarly journals Parametric Study of Air Infiltration in Residential Buildings—The Effect of Local Conditions on Energy Demand

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 127
Author(s):  
Artur Miszczuk ◽  
Dariusz Heim
Keyword(s):  
Energy Demand ◽  
Computational Models ◽  
Residential Buildings ◽  
Energy Performance ◽  
Climatic Conditions ◽  
Physical Parameters ◽  
Local Conditions ◽  
Change Rate ◽  
Air Change Rate ◽  
Wide Range

Airtightness is nowadays one of the physical parameters which determine overall building energy performance. In a wide range of states, the upper limit for air change rate at a Pa (na), air permeability rate at a Pa (qa), or specific leakage rate at a Pa (wa) is determined by the formal regulations. It should be highlighted that airtightness requirements are mainly the same around the world, disregarding any site and climatic conditions. The main goal of the presented work was to reveal the effect of individual location and surrounding infiltration rate and heat demand. The analyses were done using numerical techniques and computational models of the three buildings developed and calibrated based on the blower door test results. The compared buildings characterize by a similar geometry but differ in the air change rate at 50 Pa (n50). Analyses done for different locations and levels of sheltering by surrounding elements allow the determination of the real effect of local conditions. The obtained differences in energy demand between two locations from the same climatic zone were from 70% to 90%, depending on the airtightness of the buildings. Considering different sheltered conditions, the differences for the same location can be even 200%. The obtained results allowed for the formulation of the general conclusion that building location and level of exposure could be considered in future airtightness regulations.

scholarly journals Revealing the Impacts of Passive Cooling Techniques on Building Energy Performance: A Residential Case in Hong Kong

2020 ◽  
Vol 10 (12) ◽  
pp. 4188 ◽  
Author(s):  
Chuan-Rui Yu ◽  
Han-Sen Guo ◽  
Qian-Cheng Wang ◽  
Rui-Dong Chang
Keyword(s):  
Hong Kong ◽  
Energy Conservation ◽  
Energy Demand ◽  
Natural Ventilation ◽  
Phase Change Materials ◽  
Residential Buildings ◽  
Building Energy ◽  
Energy Performance ◽  
Passive Cooling ◽  
Total Energy Consumption

Environmental concerns and growing energy costs raise the importance of sustainable development and energy conservation. The building sector accounts for a significant portion of total energy consumption. Passive cooling techniques provide a promising and cost-efficient solution to reducing the energy demand of buildings. Based on a typical residential case in Hong Kong, this study aims to analyze the integration of various passive cooling techniques on annual and hourly building energy demand with whole building simulation. The results indicate that infiltration and insulation improvement are effective in regard to energy conservation in buildings, while the effectiveness of variations in building orientation, increasing natural ventilation rate, and phase change materials (PCM) are less significant. The findings will be helpful in the passive house standard development in Hong Kong and contribute to the further optimization work to realize both energy efficiency and favorably built environments in residential buildings.

scholarly journals A Study on the Utilization of Natural Ventilation Systems in Institutional Buildings

2019 ◽  
Vol 7 (1) ◽  
pp. 73-81
Author(s):  
N Anuja ◽  
N Amutha Priya
Keyword(s):  
Mechanical Ventilation ◽  
Energy Consumption ◽  
Wind Speed ◽  
Energy Management ◽  
Energy Demand ◽  
Natural Ventilation ◽  
Wind Pressure ◽  
Air Flow Rate ◽  
Change Rate ◽  
Air Change Rate

In Buildings, Energy Management is an important sector. Use of natural ventilation is the only way to minimise the overall energy consumption in buildings. Natural ventilation at a point can vary significantly for every second due to the climatic change. This paper has investigated energy demand problems due to ventilation in an institutional building located in India and gives satisfactory solutions to the problem. The main aim is to utilise maximum natural ventilation instead of artificial systems by reducing the energy bills in the Institutional building. Several Factors such as Wind speed, Wind pressure, Mechanical Ventilation, Air Flow Rate, Air Change Rate, Ventilation Air Change Requirements, Ventilation at various points in a Classroom are considered, and a Questionnaire Survey is conducted among the students.

scholarly journals Transition from n50 to actual air exchange dependent on climatic conditions

2019 ◽  
Vol 282 ◽  
pp. 02101
Author(s):  
Tomasz Kisilewicz ◽  
Katarzyna Nowak-Dzieszko ◽  
Małgorzata Rojewska-Warchał
Keyword(s):  
Energy Demand ◽  
Natural Ventilation ◽  
Simple Procedure ◽  
Ventilation System ◽  
Climatic Conditions ◽  
Model Calculations ◽  
Change Rate ◽  
The Real ◽  
Air Change Rate ◽  
Air Exchange

The knowledge of the air flow and air exchange in the building is critical both on the design and operation stage of the building. Infiltration of air interferes with the mechanical ventilation and determines the proper functioning of the natural ventilation system, still commonly used in the standard buildings. The building airtightness can be described by n50 parameter, however it does not specify the real air exchange in natural conditions. According to the simple procedure of the standard EN ISO 13789, factor n50 may be easily converted to the monthly averaged air change rate. However, it is difficult to accept the same value of air change rate in any month of a year, as it is often done in the certification procedures. More precise, climate dependent conversion procedures have been elaborated in USA, but they were developed for the specific local building technology and local climate conditions. This paper presents the results of the preliminary measurements conducted in a single family house in Poland, built in a heavy-weight technology. The real air exchange rate was measured in various climatic conditions by means of gas tracing method, with CO2 as the tracer gas, in order to prove a relationship between the enhanced procedure and the external conditions. Acceptable agreement between the results of the measurement and model calculations was obtained. Based on the preliminary results, the authors determined the more realistic influence of the enhanced algorithm on the ventilation energy demand. The use of the simplified model resulted in case of the analyzed object in 15% overestimation of the ventilation thermal losses.

scholarly journals Experimental Data and Simulations of Performance and Thermal Comfort in a Typical Mediterranean House

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3311
Author(s):  
Víctor Pérez-Andreu ◽  
Carolina Aparicio-Fernández ◽  
José-Luis Vivancos ◽  
Javier Cárcel-Carrasco
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Energy Demand ◽  
Natural Ventilation ◽  
Thermal Characterization ◽  
Energy Performance ◽  
Building Stock ◽  
Energy Demands ◽  
Dwelling House ◽  
Account Standard

The number of buildings renovated following the introduction of European energy-efficiency policy represents a small number of buildings in Spain. So, the main Spanish building stock needs an urgent energy renovation. Using passive strategies is essential, and thermal characterization and predictive tests of the energy-efficiency improvements achieving acceptable levels of comfort for their users are urgently necessary. This study analyzes the energy performance and thermal comfort of the users in a typical Mediterranean dwelling house. A transient simulation has been used to acquire the scope of Spanish standards for its energy rehabilitation, taking into account standard comfort conditions. The work is based on thermal monitoring of the building and a numerical validated model developed in TRNSYS. Energy demands for different models have been calculated considering different passive constructive measures combined with real wind site conditions and the behavior of users related to natural ventilation. This methodology has given us the necessary information to decide the best solution in relation to energy demand and facility of implementation. The thermal comfort for different models is not directly related to energy demand and has allowed checking when and where the measures need to be done.

scholarly journals Comparison of Downdraught and Up Draft Passive Air Conduction Systems (PACS) in a Winery Building

Buildings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 259
Author(s):  
Ádám László Katona ◽  
István Ervin Háber ◽  
István Kistelegdi
Keyword(s):  
Air Conditioning ◽  
Natural Ventilation ◽  
Dynamics Simulation ◽  
Computational Fluid Dynamics Simulation ◽  
General Applicability ◽  
Change Rate ◽  
Air Change Rate ◽  
Simulation Based ◽  
Ventilation Performance ◽  
Air Conduction

A huge portion of energy consumption in buildings comes from heating, ventilation, and air conditioning. Numerous previous works assessed the potential of natural ventilation compared to mechanical ventilation and proved their justification on the field. Nevertheless, it is a major difficulty to collect enough information from the literature to make decisions between different natural ventilation solutions with a given situation and boundary conditions. The current study tests the passive air conduction system (PACS) variations in the design phase of a medium-sized new winery’s cellar and production hall in Villány, Hungary. A computational fluid dynamics simulation based comparative analysis enabled to determine the differences in updraft (UD) and downdraught (DD) PACS, whereby the latter was found to be more efficient. While the DD PACS performed an air change range of 1.02 h−1 to 5.98 h−1, the UD PACS delivered −0.25 h−1 to 12.82 h−1 air change rate. The ventilation performance of the DD version possessed lower amplitudes, but the distribution was more balanced under different wind incident angles, thus this version was chosen for construction. It could be concluded that the DD PACS provides a more general applicability for natural ventilation in moderate climates and in small to medium scale industry hall domains with one in- and one outlet.

scholarly journals Integrating GIS-Based Point of Interest and Community Boundary Datasets for Urban Building Energy Modeling

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1049
Author(s):  
Zhang Deng ◽  
Yixing Chen ◽  
Xiao Pan ◽  
Zhiwen Peng ◽  
Jingjing Yang
Keyword(s):  
Large Scale ◽  
Residential Buildings ◽  
Building Energy ◽  
Energy Performance ◽  
Energy Modeling ◽  
Office Buildings ◽  
Building Energy Modeling ◽  
Downtown Area ◽  
Point Of Interest

Urban building energy modeling (UBEM) is arousing interest in building energy modeling, which requires a large building dataset as an input. Building use is a critical parameter to infer archetype buildings for UBEM. This paper presented a case study to determine building use for city-scale buildings by integrating the Geographic Information System (GIS) based point-of-interest (POI) and community boundary datasets. A total of 68,966 building footprints, 281,767 POI data, and 3367 community boundaries were collected for Changsha, China. The primary building use was determined when a building was inside a community boundary (i.e., hospital or residential boundary) or the building contained POI data with main attributes (i.e., hotel or office building). Clustering analysis was used to divide buildings into sub-types for better energy performance evaluation. The method successfully identified building uses for 47,428 buildings among 68,966 building footprints, including 34,401 residential buildings, 1039 office buildings, 141 shopping malls, and 932 hotels. A validation process was carried out for 7895 buildings in the downtown area, which showed an overall accuracy rate of 86%. A UBEM case study for 243 office buildings in the downtown area was developed with the information identified from the POI and community boundary datasets. The proposed building use determination method can be easily applied to other cities. We will integrate the historical aerial imagery to determine the year of construction for a large scale of buildings in the future.

scholarly journals ASSESSMENT OF ENERGY PERFORMANCE GAP OF AN OFFICE BUILDING

2021 ◽  
Vol 13 (0) ◽  
pp. 1-6
Author(s):  
Rasa Džiugaitė-Tumėnienė ◽  
Domas Madeikis
Keyword(s):  
Energy Efficiency ◽  
Energy Demand ◽  
Internal Heat ◽  
Energy Performance ◽  
Energy Model ◽  
Indoor Climate ◽  
Performance Gap ◽  
Protection Measures ◽  
Climate Parameters

The high share of global energy costs to create an indoor climate has been of increasing interest to the global community for several decades and is increasingly the focus of policy. This paper analyses the energy performance gap between actual energy consumption and energy demand obtained during the dynamic energy simulation and building certification. To identify the energy performance gap, an existing office of energy efficiency class B was selected as a case study. The simulation program IDA Indoor Climate and Energy was used to create a dynamic energy model, based on the designed documentation and the actual indoor climate parameters recorded by the building management system. The results of the case study showed that the accuracy and reliability of the results presented by the dynamic energy model of the building directly depend on the assumptions. The correct values of the internal heat gains, indoor climate parameters, human behavior, air quality levels at different times of the day and season, HVAC system operation parameters and operation modes, specific fan powers of ventilation systems, the seasonal energy efficiency of cooling equipment and characteristics of sun protection measures have to be selected.

Sign in / Sign up

Export Citation Format

Share Document