Sunday, June 25, 2017: 11:00 AM-12:30 PM
HVAC&R Systems and Equipment
Chair:
Daniel Pettway, Hobbs & Associates
Currently, the taxonomy of HVAC system and components has various basis, which can get quite complex creating ambiguity in communication, interpretation and documentation, therefore, one paper aims to develop a systematic classification. This session uses computational methods to investigate the problems of mismatch between the air and refrigerant flow distributions and propose different engineering solutions to remedy the problems. In another study, the vortex-enhanced air-side flow and heat transfer for offset strip-fin array is studied and an evenly balanced emphasis on detailed comparison of the computational results with experiments and the physics of the flow. It is of interest to determine the downstream flow field characteristics of air passing through louvers as they are primarily used in air conditioners, fans and air-coolers for directional circulation of air in a confinement.
1 Rapid Modelling of Air Flow through Louvers (LB-17-C011)
|
|
Vaibhav Arghode, Ph.D., Indian Institute of Technology - Kanpur
|
|
|
Taaresh Taneja, Indian Institute of Technology - Kanpur
|
Louvers (or vents) are primarily used in air conditioners, fans and air-coolers for directional circulation of air in a confinement. Hence, it is of interest to determine the downstream flow field characteristics of air passing through these louvers for cooling and ventilating the confinement. A detailed Computational Fluid Dynamics analysis can be done by resolving all the geometrical features of the louver and setting the appropriate boundary conditions. However, this involves high computational effort, especially, in case of physical movement of the louvers for time-varying directional delivery of the air. The central aim of this research is to develop a rapid airflow model which can replicate similar downstream flow characteristics while obviating the necessity to geometrically resolve the louver. This paper examines the results of this research.
2 Efficiency Enhancement of a V-Shaped Evaporator (LB-17-C012)
|
|
Zongqin Zhang, Ph.D., Nanjing Canatal A/C Co., Ltd
|
|
|
Haijin Xu, P.E., Nanjing Canatal A/C Co., Ltd
|
|
|
Xinyu Zhang, P.E., University of Rhode Island
|
|
|
Weixin Zhang, P.E., Nanjing Canatal A/C Co., Ltd
|
|
|
Donna M. L. Meyer, Ph.D., University of Rhode Island
|
Air finned-tube evaporators and/or condensers, are the predominant type of heat exchangers used in building air conditioning applications. The compact V-shaped, or sometimes called A–shaped, finned-tube heat exchanger installation considerably enhance the capacity of heat transfer by allowing the maximum number of coils installed in a given space and increasing the total surface area of heat transfer. On the other hand, this design configuration creates noticeable problems of uneven distribution of air flow velocity over the heat exchanger surfaces, which decreases the energy efficiency of the air conditioning system. This paper uses computational methods to investigate the problems of mismatch between the air and refrigerant flow distributions and propose different engineering solutions at air flow side as well as refrigerant flow side to remedy the problems.
3 Flow and Heat Transfer in Vortex-Enhanced Offset Strip-Fin Array, Numerical Study (LB-17-C013)
|
|
Arindom Joardar, Ph.D., Carrier Corporation
|
|
|
Anthony Jacobi, University of Illinois at Urbana Champaign
|
Streamwise longitudinal vortex generation is a promising method for enhancing air-side heat transfer performance of heat exchangers in a range of applications. In this paper, the vortex-enhanced air-side flow and heat transfer for offset strip-fin array is studied with an emphasis on understanding the relation between flow structure and heat transfer. The flow and heat transfer behavior of the baseline offset strip-fin geometry has been thoroughly investigated both experimentally and numerically in the literature. However, numerical modelling of vortex generator (VG) enhanced offset-strip fin array has not been reported. The predictive capability of the model in terms of the local flow and heat transfer characteristics is evaluated in such geometry for both baseline and enhanced cases.
4 A Systematic Classification for HVAC Systems and Components (LB-17-C014)
|
|
Han Li, Carnegie Mellon University
|
Currently, the taxonomy of HVAC system and components has various basis, which can get quite complex because of the various components and system configurations. In addition, some of the system names might be commonly used in a confusing manner, such as “unitary system” vs. “packaged system.” Without a systematic classification, these components and system terminology can be confusing to understand or differentiate from each other, and it creates ambiguity in communication, interpretation, and documentation. It is valuable to organize and classify HVAC systems and components so that they can be easily understood and used in a consistent manner. This paper aims to develop a systematic classification of HVAC systems and components.
