• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.9
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• pp.416-423
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• 2014

To verify different boundary conditions on the borehole wall, which are commonly used for generating g-function, the well-known TRNSYS simulation model, DST (Duct STorage), is employed. By letting the fluid circulation determine the borehole wall conditions, a DST-based g-function is induced with numerical processes proposed in this work. A new TRNSYS module is also developed to accommodate g-function data and predict dynamic outlet fluid temperatures. Results showed that the modified g-function, which is different from Eskilson's original g-function, is closer to the DST-based g-function. This implies that the uniform heat transfer rates over the height can be used for good approximation. In fact, simulations with the modified g-function showed similar results as the DST model, while Eskilson g-function case deviated from the DST model as time progressed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.2
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• pp.112-121
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• 2006

To evaluate the performance of ventilation system properly, the correlations among the ventilation rate, indoor air-quality and cooling/heating load should be analysed. In this study, simulation tool to analyze the performance of ventilation system was developed. The simulation tool is based on the TRNSYS and some modules to calculate concentration of pollutants with the operation of ventilation system and to decide the signal of ventilation system were newly developed in this study. And these modules coupled with building load and heating/cooling simulation modules. To verify the validity of developed simulation tool, comparison study between simulation and field study were accomplished. As results, the simulation tool developed in this study can be used to predict the performance of ventilation system with accuracy.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.4
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• pp.315-322
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• 2012

In these days, importance of HVAC system in office building is steadily growing in terms of thermal comfort and energy savings. As a energy efficient heating and cooling system, system air-conditioner which can be controlled distinctly and has a high COP is more widely adopted nowadays. However, the features and advantages of system air-conditioner were not reported well because system air-conditioner did not describe yet by conventional simulation methods such as TRNSYS, e-Quest, Energyplus, etc. In this study, by using the TRNSYS program which is able to show module implementation and building energy consumption analysis, system air-conditioner module will be proposed and validated through comparison between the simulation results and measurement results.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.7
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• pp.386-391
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• 2013

The dynamic characteristics of both raw-water source and air source heat pump utilized in water treatment facilities were investigated by using TRNSYS simulator. The modeling of the raw water source heat pump was verified by the measured data at the Cheongju water treatment facility, and the modeling at the air source heat pump was verified by the data from the Siheung water treatment facility. The average heating and cooling COPs from the raw-water source heat pump were higher than those of the air source heat pump by 19% and 18%, respectively. The power consumptions of the air source heat pump for the cooling and the heating were higher than those of the raw water source heat pump by 28% and 26%, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.59.2-59.2
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• 2011

This study presents a new method for coupling ArcGIS (popular GIS software) with TRaNsient SYstems Simulation (TRNSYS, reference software for researchers and engineers around the world) to use capabilities of the 4 and 5-parameter PV array performance models within the ArcGIS environment. Using the validated and industry-proven solar energy simulation models implemented in TRNSYS and other built-in ArcGIS functionalities, dynamic characteristics of distributed PV potential in terms of hourly, daily or monthly power outputs can be investigated with considerations of diverse options in selecting and mounting PV panels. In addition, the proposed method allows users to complete entire procedures in a single framework (i.e., a preliminary site survey using 3D building models, shading analyses to investigate usable rooftop areas with considerations of different sizes and shapes of buildings, dynamic energy simulation to examine the performances of various PV systems, visualization of the simulation results to understand spatially and temporally distributed patterns of PV potential). Therefore tedious tasks for data conversion among multiple softwares can be significantly reduced or eliminated. While the programming environment of TRNSYS is proprietary, the redistributable executable, simulation kernel and simulation engine of TRNSYS can be freely distributed to end-users. Therefore, GIS users who do not have a license of TRNSYS can also use the functionalities of solar energy simulation models within ArcGIS.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.294-301
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• 2018

In winter, thermal screens are widely used to reduce heat loss from greenhouse to save energy. Unfortunately, not much data are available to the farmer to compare thermal screens while selecting the one that meets their specific requirements. Thus, there is a need to investigate the thermal performance of thermal screens. To address this issue, the Building Energy Simulation (BES) model of a hot box was used to calculate the overall heat transfer coefficient (U-value) of the thermal screens. To validate the model, computed and experimental U-values of single-and double-layered polyethylene (PE) material were compared. This validated model was used to predict the U-values of the selected thermal screens under defined weather conditions. We quantified the U-values of each selected material and significant changes in their U-values were noted in response to different weather conditions. Notably, the thermal properties of the tested screens were taken from the previous literature to calculate U-values using the BES model. The U-values of the thermal screens can help researchers and farmers evaluate their screens and make pre-design decisions that suit their investment capabilities.

• Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
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• v.12 no.6
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• pp.531-542
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• 2018

Building energy demands have highly risen in modern society; thus, It is necessary to reduce building energy demands especially commercial buildings adopting a curtain wall architecture. Curtain wall architectures have a high ratio of windows which is a vulnerable in heat insulations as cladding. In order to complement insulation performance of windows in these buildings, there are various methods adopted often such as installing blinds, wing wall and films. There are two suggestions of this paper. 1) WWR (Window-to-Wall Ratio) makes a impaction of energy demands in buildings. 2) Another one is an efficiency of blind systems which are installed in buildings in order to reduce cooling demands. It is also critical to make fundamental model for low-energy building construction by processing a lot of simulation As a result by this study, 1) an external blind system is more useful for reducing cooling energy demands rather than an internal blind system. 2) Buildings which have a large window require more amount of cooling demands. In case of WWR 45%, it needs more cooling energy rather than WWR 15% model's 3) Adopting blind system would reduce energy demands. WWR 45% model with external blind systems reduces about 4% of cooling energy demands compared to same model without any blind systems.4) it is necessary to study an efficiency of blind systems combined with renewable energy and it will be possible to reduce more energy demand in building significantly.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.317-325
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• 2015

This paper attempts to present a review about simulation of different greenhouse parameters and energy supplying techniques by using building energy simulation, to find out the optimal solution for keeping greenhouse microclimate favorable for the crop production. The objectives of conducting this study were, to describe the various energy systems and techniques used for the greenhouse energy management and efficiency analysis of these technologies by using building energy simulation. We describe different models to understand the behavior of the energy saving technologies with respect to the resources available and different outside climatic conditions. We identified main features of the building energy simulation software, that enable users, to simulate hybrid agricultural building projects by using user defined parameters. At the end of the paper we draw some important concluding remarks on the basis of reviewing all the investigators contributions for the developments of simulation model of agricultural greenhouse energy management, using a building energy simulation software specifically TRNSYS. In conclusion, this paper provides information that TRNSYS have great potential for agricultural buildings energy simulation along with the renewable energy resources and energy saving techniques. This review paper provides aid to greenhouse researcher and energy planner for the future studies of greenhouses energy planning.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.11
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• pp.421-427
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• 2016

The indoor temperature of a building increases during the day due to solar radiation. This behavior is significant in school buildings that are finished with high thermal capacity materials. Moreover, in school buildings, windows cannot be opened until the class has finished owing to the security policy of schools. Consequently, classrooms maintain a high temperature throughout the morning. It is thus important to remove the indoor heat before the commencement of classes in order to reduce the cooling energy needed. The Energy Recovery Ventilator (ERV) system is currently being installed in school buildings for ventilating the classrooms. Night-purge control using ERV can be a good strategy to cool the classroom in advance of the operation of the cooling system. However, the optimal operation method of the ERV for night-purge control has not yet been reported. In this study, the effect of night-purge control with ERV in school buildings is analyzed by simulation method. The results of this study showed that the energy saving effect of night-purge control with ERV is most effective in the case of 2 hours operation prior to the commencement of the first lass and when enthalpy based outdoor air cooling is used.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.5
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• pp.467-472
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• 2013

A raw-water source heat pump equipped with a thermal storage tank was dynamically simulated by TRNSYS, and the results were verified by using the data from a heat pump installed in the Seongnam water treatment facility. The average coefficient of performance (COP) of the raw-water source heat pump based on simulation was 4.97 and 3.17 in the cooling and heating season, respectively. When the volume of the thermal storage tank was changed from 5 to $20m^3$, the highest COP was found at a size of $10m^3$. Considering the regional locations of raw-water source heat pumps at Seoul, Incheon, Gangneung, and Gwangju, Seoul showed the lowest electric power consumption in the cooling season and the highest in the heating season. When a comparison of the performance between the present system and that of a water-air heat pump was conducted, the present system showed lower electric power consumption by 25% than that of a water-air heat pump.