scholarly journals Simulation and Measurement of Energetic Performance in Decentralized Regenerative Ventilation Systems

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 6010
Author(s):  
Nicolas Carbonare ◽  
Hannes Fugmann ◽  
Nasir Asadov ◽  
Thibault Pflug ◽  
Lena Schnabel ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Heat Recovery ◽  
Residential Buildings ◽  
Simulation Models ◽  
Hydraulic Modeling ◽  
Test Facility ◽  
Test Case ◽  
Building Performance ◽  
Regenerative Heat ◽  
Ventilation Systems

Decentralized regenerative mechanical ventilation systems have acquired relevance in recent years for the retrofit of residential buildings. While manufacturers report heat recovery efficiencies over 90%, research has shown that the efficiencies often vary between 60% and 80%. In order to better understand this mismatch, a test facility is designed and constructed for the experimental characterization and validation of regenerative heat exchanger simulation models. A ceramic honeycomb heat exchanger, typical for decentralized regenerative ventilation devices, is measured in this test facility. The experimental data are used to validate two modeling approaches: a one-dimensional model in Modelica and a computational fluid dynamics (CFD) model built in COMSOL Multiphysics®. The results show an overall acceptable thermal performance of both models, the 1D model having a much lower simulation time and, thus, being suitable for integration in building performance simulations. A test case is designed, where the importance of an appropriate thermal and hydraulic modeling of decentralized ventilation systems is investigated. Therefore, the device is integrated into a multizone building simulation case. The results show that including component-based heat recovery and fan modeling leads to 30% higher heat losses due to ventilation and 10% more fan energy consumption than when assuming constant air exchange rates with ideal heat recovery. These findings contribute to a better understanding of the behavior of a growing technology such as decentralized ventilation and confirm the need for further research on these systems.

NUMERICAL SIMULATION AND PARAMETRIC STUDIES FOR EVALUATION OF BALANCED VENTILATION AND EARTH AIR EXCHANGERS SYSTEM COUPLED TO A DOMESTIC BUILDING

2013 ◽  
Vol 21 (01) ◽  
pp. 1350002 ◽  
Author(s):  
YOUNES KARTACHI ◽  
ABDELLAH MECHAQRANE
Keyword(s):  
Heat Exchanger ◽  
Heat Recovery ◽  
High Efficiency ◽  
Residential Buildings ◽  
Ventilation System ◽  
Primary Energy ◽  
Climatic Conditions ◽  
Design Parameters ◽  
Climate Data ◽  
The Impact

In this study, we analyze the impact of ventilation heat recovery with the heating and cooling potential of earth air heat exchanger in real climatic conditions in domestic buildings in the Middle Atlas region. In our case study, we calculate the primary energy used by a domestic building built as per the conventional house design parameters required by the Moroccan regulation. We use climate data for the city of Fes in Northern Moroccan. Three system configurations were considered. The first was the mechanical extract ventilation system both with and without heat recovery. The second was the mechanical extract ventilation system with earth to air heat exchanger system (EAHEX), and the third system was the mechanical balanced ventilation system coupled with EAHEX system. Primary energy use strongly influences natural resources efficiency and the environmental impacts of energy supply activities. In this study we explore the primary energy implications of the mechanical balanced ventilation system coupled with the EAHEX system in residential buildings. The results of this study shows that the use of a balanced ventilation system, with a high efficiency instead of a mechanical extract ventilation system, decreases the final and primary energy consumption. Moreover, it decreases or increases the CO2 emission depending on the primary energy sources.

Experimental analysis of an air-to-air heat recovery unit for balanced ventilation systems in residential buildings

2011 ◽  
Vol 52 (1) ◽  
pp. 635-640 ◽  
Author(s):  
José Fernández-Seara ◽  
Rubén Diz ◽  
Francisco J. Uhía ◽  
Alberto Dopazo ◽  
José M. Ferro
Keyword(s):  
Experimental Analysis ◽  
Heat Recovery ◽  
Residential Buildings ◽  
Recovery Unit ◽  
Ventilation Systems

scholarly journals Review of Heat Recovery Technologies for Building Applications

Energies ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1285 ◽  
Author(s):  
Qi Xu ◽  
Saffa Riffat ◽  
Shihao Zhang
Keyword(s):  
Heat Recovery ◽  
High Performance ◽  
Natural Ventilation ◽  
Residential Buildings ◽  
Global Climate ◽  
Real Life ◽  
Thermal Conductance ◽  
Thermoelectric Module ◽  
Residential Building ◽  
Ventilation Systems

In recent years, interest in heat recovery systems for building applications has resurged due to concerns about the energy crisis and global climate changes. This review presents current developments in four kinds of heat recovery systems for residential building applications. A extensive investigation into the heat recovery integrated in energy-saving systems of residential buildings is also covered, including passive systems for building components, mechanical/natural ventilation systems, dehumidification systems, and the thermoelectric module (TE) system. Based on this review, key issues have been identified as follows: (1) The combination of heat recovery and energy-efficient systems could be considered as a promising approach to reduce greenhouse gas emissions and make residential buildings meet high performance and comfort requirements. However, real-life evaluation of these systems with economic analysis is insufficient; (2) When heat recovery is applied to mechanical ventilation systems, issues such as pressure leakages and air shortcuts should be addressed; (3) The heat pipe heat recovery system enjoys more potential in being combined with other sustainable technologies such as thermoelectric modules and solar energy systems due to its advantages, which include handy manufacturing and convenient maintenance, a lack of cross contamination, and greater thermal conductance.

scholarly journals Minimization of the Lifecycle Cost of a Rotary Heat Exchanger Used in Building Ventilation Systems in Cold Climates

2021 ◽  
Vol 67 (6) ◽  
pp. 302-310
Author(s):  
Ignas Sokolnikas ◽  
Kęstutis Čiuprinskas ◽  
Jolanta Čiuprinskienė
Keyword(s):  
Heat Exchanger ◽  
Heat Exchangers ◽  
Heat Recovery ◽  
Foil Thickness ◽  
Geometrical Parameters ◽  
Cold Climates ◽  
Heat Transfer Efficiency ◽  
Air Handling Unit ◽  
Building Ventilation ◽  
Ventilation Systems

This article presents an analysis of rotary heat exchangers (RHE) used as heat recovery units in building ventilation systems in cold climates. Usually, heat exchangers with the highest heat transfer efficiency are the preferable option for this purpose. However, such exchangers usually have the highest media pressure drop, thus requiring the highest amount of energy for media transportation. In this study, the problem is solved by analysing the lifecycle cost (LCC) of the RHE including both the recovered heat and the electricity consumed in the fans of the air handling unit (AHU). The purpose of the investigation was to determine the optimal set of geometrical characteristics such as the exchanger’s length, foil thickness, the height and width of the air channel. Two hundred and seventy different combinations were examined using analytical dependencies and ANSYS simulations. The results are compared with experimental data obtained earlier at the KOMFOVENT laboratory. The results show that the best overall energy efficiency is obtained in heat exchangers that do not offer the best heat recovery efficiency, and LCC differences in the same climatic and economic conditions can go as high as 31 %, mainly due to the geometrical parameters of the heat exchanger.

Decentralized Ventilation Systems with Exhaust Air Heat Recovery in the Case of Residential Buildings

2014 ◽  
Vol 680 ◽  
pp. 524-528 ◽  
Author(s):  
Vera Murgul ◽  
Dusan Vuksanovic ◽  
Nikolay Vatin ◽  
Viktor Pukhkal
Keyword(s):  
Heat Recovery ◽  
Residential Buildings ◽  
Basic System ◽  
Ventilation Systems

Decentralized ventilation systems applied in residential buildings are generalized in this article. Basic system elements and devices and tools assigned for its application are considered herein. Basic requirements for design of the ventilation systems used in residential buildings are stipulated.

scholarly journals A Novel Spherical Packed Bed Application on Decentralized Heat Recovery Ventilation Units

2019 ◽  
Vol 111 ◽  
pp. 01012
Author(s):  
Alper Mete GENC ◽  
Ziya Haktan KARADENIZ ◽  
Orhan EKREN ◽  
Macit TOKSOY
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Heat Recovery ◽  
Thermal Power ◽  
Packed Bed ◽  
Small Scale ◽  
Regenerative Heat ◽  
Operation Conditions ◽  
Cyclic Operation ◽  
Wide Range

Decentralized heat recovery ventilation (HRV) systems are assumed as simple solutions to obtain a healthy and comfortable indoor environment. A wall or window mounted compact version of decentralized HRV systems (mono unit) are used for small scale, mostly residential applications. A fan and a heat exchanger are the critical components of this compact system. The flow capacity of these units are down to 10 m3/h, where efficiencies over 90% are commonly declared by the manufacturers. On the other hand, spherical packed beds (SPD) are widely used in the heat transfer applications such as; chemical reactors, grain driers, nuclear reactors, thermal storage in buildings and in solar thermal power plants, due to operational convenience. These systems are operated under steady flow conditions, unlike decentralized HRV systems which are designed for cyclic operation. In this study, heat recovery performance of a spherical packed bed heat exchanger for a decentralized HRV system is investigated. A one dimensional mathematical model for a SPD is obtained and an in-house computer code is developed to solve the transient heat transfer inside the packed bed under cyclic operation conditions. Well known convenient correlations were used for pressure drop calculations. A number of bed and sphere diameters were studied in a wide range. Various flow time and number of cycles were studied for the hot and cold flow to understand the SPD performance for HRV applications. This novel application also has the potential for regenerative heat recovery systems.

scholarly journals Numerical analysis and simulation of the heat recovery from wastewater using heat exchanger

2018 ◽  
Vol 240 ◽  
pp. 02005
Author(s):  
Timea Gabor ◽  
Ancuta-Elena Tiuc ◽  
Ioana Monica Sur ◽  
Iulian Nicolae Badila
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Heat Recovery ◽  
Residential Buildings ◽  
Background Information ◽  
Mass And Heat Transfer ◽  
Increasing Demand ◽  
Reduction Of Energy Consumption ◽  
Pipe Heat

The problem of global warming and the reduction of energy consumption have led to an evolutionary progress of research directed towards finding as many solutions as possible to these environmental issues. Firstly, this paper presents the background information on the role of wastewater as a source of heat for the future. Next, the paper includes the analysis elements that define a system for recovering thermal energy from wastewater. The main objective was to identify the parameters that determine the heat transfer. It has started from a conceptual model of the technological system that involves inputs and outputs characterized by technological, physical-chemical, measurable or imposed properties. In the second part this paper presents a numerical model elaborated for the analysis and simulation of the main physical processes, the mass and heat transfer, which underlie the operation of the heat pipe heat exchangers (HPHE). The numerical simulation of heat and mass transfer in the HPHE is computed by using Delphi 7 solver program. This program contained a series of sub-programs for the meshing of the field occupied by the HPHE, another subprogram for solving the meshing equations and the third for post processing. The design of HPHE is the key to provide a heat exchanger system to work proficient as expected. Finally, the result is used to optimize and improving heat recovery systems of the increasing demand for energy efficiency in residential buildings or industry.

Sign in / Sign up

Export Citation Format

Share Document