@article {31669, title = {A novel approach for selecting typical hot-year (THY) weather data}, journal = {Applied Energy}, volume = {242}, year = {2019}, month = {03/2019}, pages = {1634 - 1648}, abstract = {

The global climate change has resulted in not only warmer climate conditions but also more frequent extreme weather events, such as heat waves. However, the impact of heat waves on the indoor environment has been investigated in a limited manner. In this research, the indoor thermal environment is analyzed using a building performance simulation tool for a typical residential building in multiple cities in China, over a time period of 60 years using actual measured weather data, in order to gain a better understanding of the effect of heat wave events. The simulation results were used to analyze the indoor environment during hot summers. A new kind of weather data referred to as the typical hot year was defined and selected based on the simulated indoor environment during heat waves. The typical hot-year weather data can be used to simulate the indoor environment during extreme heat events and for the evaluation of effective technologies and strategies to mitigate against the impact of heat waves on the energy demand of buildings and human health. The limitations of the current study and future work are also discussed.

}, keywords = {Actual weather data, dest, Heat wave, Multiyear simulation, Residential indoor thermal environment, Typical hot year}, issn = {03062619}, doi = {10.1016/j.apenergy.2019.03.065}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0306261919304659}, author = {Siyue Guo and Da Yan and Tianzhen Hong and Chan Xiao and Ying Cui} } @article {30486, title = {A Novel Variable Refrigerant Flow (VRF) Heat Recovery System Model: Development and Validation}, journal = {Energy and Buildings}, volume = {168}, year = {2018}, abstract = {

As one of the latest emerging HVAC technologies, the Variable Refrigerant Flow (VRF) system with heat recovery (HR) configurations has obtained extensive attention from both the academia and industry. Compared with the conventional VRF systems with heat pump (HP) configurations, VRF-HR is capable of recovering heat from cooling zones to heating zones and providing simultaneous cooling and heating operations. This can further lead to substantial energy saving potential and more flexible zonal control. In this paper, a novel model is developed to simulate the energy performance of VRF-HR systems. It adheres to a more physics-based development with the ability to simulate the refrigerant loop performance and consider the dynamics of more operational parameters, which is essential for representing more advanced control logics. Another key feature of the model is the introduction of component-level curves for indoor units and outdoor units instead of overall performance curves for the entire system, and thus it requires much fewer user-specified performance curves as model inputs. The validation study shows good agreements between the simulated energy use from the new VRF-HR model and the laboratory measurement data across all operational modes at sub-hourly time steps. The model has been adopted in the official release of the EnergyPlus simulation program since Version 8.6, which enables more accurate and robust assessments of VRF-HR systems to support their applications in energy retrofit of existing buildings or design of zero-net-energy buildings.

}, keywords = {building performance simulation, controls, energy modeling, heat recovery, validation, Variable refrigerant flow}, doi = {10.1016/j.enbuild.2018.03.028}, author = {Rongpeng Zhang and Kaiyu Sun and Tianzhen Hong and Yoshinori Yura and Ryohei Hinokuma} } @article {29897, title = {A Novel Stochastic Modeling Method to Simulate Cooling Loads in Residential Districts}, year = {2017}, abstract = {

District cooling systems are widely used in urban residential communities in China. Most district cooling systems are oversized;this leads to wasted investment and low operational efficiency and thus energy wastage. The accurate prediction of district cooling loads that supports rightsizing cooling plant equipment remains a challenge. This study developed a new stochastic modeling method that includes (1) six prototype house models representing a majority of apartments in the district, (2)occupant behavior models in residential buildings reflecting the temporal and spatial diversity and complexity based on a large-scale residential survey in China, and (3) a stochastic sampling process to represent all apartments and occupants in the district. The stochastic method was employed in a case study using the DeST simulation engine to simulate the cooling loads of a real residential district in Wuhan, China. The simulation results agree well with the actual measurement data based on five performance metrics representing the aggregated cooling loads, the peak cooling loads as well as the spatial load distribution,and the load profiles. Two currently used simulation methods were also employed to simulate the district cooling loads. The simulation results showed that oversimplified occupant behavior assumptions lead to significant overestimations of the peak cooling load and total district cooling loads. Future work will aim to simplify the workflow and data requirements of the stochastic method to enable its practical application as well as explore its application in predicting district heating loads and in commercial or mixed-use districts.

}, author = {Jingjing An and Da Yan and Tianzhen Hong and Kaiyu Sun} } @conference {59967, title = {A New Model to Simulate Energy Performance of VRF Systems}, year = {2014}, abstract = {

This paper presents a new model to simulate energy performance of variable refrigerant flow (VRF) systems in heat pump operation mode (either cooling or heating is provided but not simultaneously). The main improvement of the new model is the introduction of the evaporating and condensing temperature in the indoor and outdoor unit capacity modifier functions. The independent variables in the capacity modifier functions of the existing VRF model in EnergyPlus are mainly room wet-bulb temperature and outdoor dry-bulb temperature in cooling mode and room dry-bulb temperature and outdoor wet-bulb temperature in heating mode. The new approach allows compliance with different specifications of each indoor unit so that the modeling accuracy is improved. The new VRF model was implemented in a custom version of EnergyPlus 7.2. This paper first describes the algorithm for the new VRF model, which is then used to simulate the energy performance of a VRF system in a Prototype House in California that complies with the requirements of Title 24 {\textendash} the California Building Energy Efficiency Standards. The VRF system performance is then compared with three other types of HVAC systems: the Title 24-2005 Baseline system, the traditional High Efficiency system, and the EnergyStar Heat Pump system in three typical California climates: Sunnyvale, Pasadena and Fresno. Calculated energy savings from the VRF systems are significant. The HVAC site energy savings range from 51 to 85\%, while the TDV (Time Dependent Valuation) energy savings range from 31 to 66\% compared to the Title 24 Baseline Systems across the three climates. The largest energy savings are in Fresno climate followed by Sunnyvale and Pasadena. The paper discusses various characteristics of the VRF systems contributing to the energy savings. It should be noted that these savings are calculated using the Title 24 prototype House D under standard operating conditions. Actual performance of the VRF systems for real houses under real operating conditions will vary.

}, author = {Tianzhen Hong and Xiufeng Pang and Oren Schetrit and Liping Wang and Shinichi Kasahara and Yoshinori Yura and Ryohei Hinokuma} } @article {226, title = {Neue objektorientierte hygrothermische Modell-Bibliothek zur Ermittlung des hygrothermischen und hygienischen Komforts in R{\"a}umen}, journal = {Bauphysik}, volume = {31}, number = {5}, year = {2009}, pages = {271-278}, issn = {0171-5445}, doi = {10.1002/bapi.200910036}, author = {Thierry Stephane Nouidui and Klaus Sedlbauer and Christoph Nytsch-Geusen and Kurt Kie{\ss}l} } @conference {287, title = {Natural ventilation simulation by using coupling building simulation and CFD simulation program for accurate prediction of indoor thermal environment}, booktitle = {the 23st International conference on Passive and Low energy architecture , Geneva}, year = {2006}, month = {09/2006}, author = {Liping Wang and Nyuk Hien Wong} } @conference {289, title = {A numerical study of Trombe wall for enhancing stack ventilation in buildings}, booktitle = {The 23rd International Conference on Passive and Low Energy Architecture, Geneva}, year = {2006}, month = {09/2006}, author = {Liping Wang and Angui Li} } @conference {2664, title = {Natural Ventilation Analysis of an Office Building with Open Atrium}, booktitle = {IBPSA Building Simulation 2005}, year = {2005}, month = {08/2005}, address = {Montreal, canada}, author = {Mohit Mehta} } @proceedings {2821, title = {Near Real-Time Weather Data Archive}, journal = {SimBuild 2004, Building Sustainability and Performance Through Simulation}, year = {2004}, month = {08/2004}, address = {Boulder, Colorado, USA}, author = {Nicholas Long} } @conference {296, title = {A numerical study of vertical solar chimney for Enhancing stack ventilation in buildings}, booktitle = {The 21st International Conference on Passive and Low Energy Architecture, The Netherlands}, year = {2004}, month = {09/2004}, author = {Liping Wang and Angui Li} } @proceedings {398, title = {Numerical Tools For Particle- Fluid Interactions}, journal = {Pulmonary Research Forum: American Lung Association of Arizona \& New Mexico}, year = {2004}, month = {02/2004}, author = {R. Calhoun and Patrick E. Phelan and Ajay K. Yadav and Prajesh Bhattacharya} } @proceedings {298, title = {Non-Linear Recursive Parameter Estimation Applied to Fault Detection and Diagnosis in Real Buildings}, journal = {System Simulation in Buildings {\textquoteright}02}, year = {2002}, month = {12/2002}, address = {Li{\`e}ge, Belgium}, author = {Richard A. Buswell and Philip Haves and Tim I. Salsbury and Jonathan A. Wright} } @article {303, title = {A Nodal Model for Displacement Ventilation and Chilled Ceiling Systems in Office Spaces}, journal = {Building and Environment}, volume = {36}, year = {2001}, month = {07/2001}, pages = {753-762}, chapter = {753}, abstract = {

A nodal model has been developed to represent room heat transfer in displacement ventilation and chilled ceiling systems. The model uses precalculated air flow rates to predict the air temperature distribution and the division of the cooling load between the ventilation air and the chilled ceiling. The air movements in the plumes and the rest of the room are represented separately using a network of ten air nodes. The values of the capacity rate parameters are calculated by solving the heat and mass balance equations for each node using measured temperatures as inputs. Correlations between parameter values for a range of cooling loads and supply air flow rates are presented.

}, keywords = {Chilled ceilings, commercial buildings, Displacement ventilation, energy, Heat Transfer, Nodal model, simulation}, doi = {10.1016/S0360-1323(00)00067-6}, url = {http://www.ibpsa.org/proceedings/BS1999/BS99_D-05.pdf}, author = {Simon J. Rees and Philip Haves} } @article {307, title = {Numerical Investigation of Transient Buoyant Flow in a Room with a Displacement Ventilation and Chilled Ceiling System}, journal = {International Journal of Heat and Mass Transfer}, volume = {44}, year = {2001}, month = {08/2001}, pages = {3067-3080}, chapter = {3067}, abstract = {

The air flow in the office ventilation system known as displacement ventilation is dominated by a gravity current from the inlet and buoyant plumes above internal heat sources. Calculations of the flow and heat transfer in a typical office room have been made for this type of ventilation system used in conjunction with chilled ceiling panels. These calculations have been made in parallel with full size test chamber experiments. It has been found that with higher values of internal load (45 and 72 W m-2 of floor area) the flow becomes quasi-periodic in nature. Complex lateral oscillations are seen in the plumes above the heat sources which impinge on the ceiling and induce significant recirculating flows in the room. The frequency spectra of the transient calculations show good agreement with those of the experimental results. Comparison is also made between calculated mean room air speeds and temperature profiles and measured values.

}, doi = {10.1016/S0017-9310(00)00348-3}, url = {http://www.sciencedirect.com/science/article/pii/S0017931000003483}, author = {Simon J. Rees and James J. McGuirk and Philip Haves} } @proceedings {316, title = {A Nodal Model for Displacement Ventilation and Chilled Ceiling Systems in Office Spaces}, journal = {Building Simulation {\textquoteright}99}, year = {1999}, month = {09/1999}, address = {Kyoto, Japan}, abstract = {

A nodal model has been developed to represent room heat transfer in displacement ventilation and chilled ceiling systems. The model uses precalculated air flow rates to predict the air temperature distribution and the division of the cooling load between the ventilation air and the chilled ceiling. The air movements in the plumes and the rest of the room are rep- resented separately using a network of ten air nodes. The values of the capacity rate parameters are calculated by solving the heat and mass balance equations for each node using measured temperatures as inputs. Correlations between parameter values for a range of cooling loads and supply air flow rates are presented.

}, url = {http://www.ibpsa.org/proceedings/BS1999/BS99_D-05.pdf}, author = {Simon J. Rees and Philip Haves} } @proceedings {315, title = {Numerical Performance of a Graph-Theoretic HVAC Simulation Program}, journal = {Building Simulation {\textquoteright}99}, year = {1999}, month = {09/1999}, address = {Kyoto, Japan}, abstract = {The Simulation Problem Analysis and Research Kernel (SPARK) uses graph-theoretic techniques to match equations to variables and build computational graphs, yielding solution sequences indicated by needed data flow. Additionally, the problem graph is decomposed into strongly connected components, thus reducing the size of simultaneous equation sets, and small cut sets are determined, thereby reducing the number of iteration variables needed to solve each equation set. The improvement in computational efficiency produced by this graph theoretic preprocessing depends on the nature of the problem. The paper explores the improvement one might expect in practice in three ways. First, two problems chosen to span the range of performance are studied and some of the factors determining the performance are identified and discussed. The problem selected to exhibit a large improvement consists of a set of sparsely coupled non-linear equations. The problem selected to represent the other end of the performance spectrum is a set of equations obtained by discretizing Laplace{\textquoteright}s equation in two dimensions, e.g. a heat conduction problem. Execution time versus problem size is compared to that obtained with sparse matrix implementations of the same problems. Then, to see if the results of these somewhat contrived limiting cases extend to actual problems in building simulation, a detailed control system model of a six- zone VAV HVAC system is simulated with and without the use of cut set reduction. Execution times are compared between the reduced and non-reduced SPARK models, and with those from an HVACSIM+ model of the same system.}, url = {http://www.ibpsa.org/proceedings/BS1999/BS99_A-05.pdf}, author = {Edward F. Sowell and Philip Haves} } @article {425, title = {A new multizone model for simulation of building thermal performance}, journal = {Building and Environment}, volume = {32}, year = {1997}, month = {1997}, pages = {123-128}, type = {Research Article}, abstract = {

A new multizone model which is an improvement on the state space model is presented, which is potentially more efficient in the simulation of large scale buildings than other methods such as finite difference, transfer functions, or finite volume. The modeling philosophy is firstly discussed. Then the principle and algorithm of the new model are described. Finally, a PC based program BTP developed based on state-of-the-art modeling strategy reveals its applicability with fast calculation speed and satisfactory accuracy in the modeling of building energy performance.

}, doi = {10.1016/S0360-1323(96)00045-5}, author = {Tianzhen Hong and Yi Jiang} } @article {384, title = {Nanofluids for Heat Transfer Applications}, journal = {Annual Review of Heat Transfer}, volume = {14}, year = {1995}, pages = {255-275}, chapter = {255}, author = {Patrick E. Phelan and Ravi S. Prasher and Prajesh Bhattacharya} } @proceedings {55943, title = {New Features of the DOE-2.1c Energy Analysis Program}, journal = {International Building Performance Simulation Association}, year = {1985}, month = {01/1985}, publisher = {International Building Performance Simulation Association}, url = {http://www.ibpsa.org/proceedings/BS1985/BS85_195_200.pdf}, author = {Walter F. Buhl and Ender Erdem and Joseph H. Eto and James J. Hirsch and Frederick C. Winkelmann} }