Determination of the economical optimum insulation thickness for VRF (variable refrigerant flow) systems

This study deals with the investigation into optimum insulation thickness of installed inside building pipe network of VRF (variable refrigerant flow) systems. Optimum insulation thickness, energy savings over a lifetime of 10 years and payback periods are determined for high pressure gas pipelines, low pressure gas pipelines and low pressure liquid pipelines under the heating-only and cooling-only modes of the three-pipe VRF system using R-410A as refrigerant. By using the P1–P2 method, the value of the amount of the net energy savings is calculated. Under heating mode of VRF system, while the optimum insulation thickness varies between 16 and 20 mm depending on the pipe sections of high pressure gas pipeline, it varies from 11 to 13 mm for the pipe sections of low pressure liquid pipeline. Under cooling mode of VRF system, the optimum insulation thickness varies between 7 and 8 mm for pipe sections of low pressure gas pipeline and low pressure liquid pipeline.

[1]  Hari B. Vuthaluru,et al.  A simple method for the estimation of thermal insulation thickness , 2010 .

[2]  Tolga N. Aynur,et al.  Variable refrigerant flow systems: A review , 2010 .

[3]  P. Jaruyanon,et al.  The Thermo-Economics Analysis of the Optimum Thickness of Double-Layer Insulation for Air Conditioning Duct , 2010 .

[4]  Ali Keçebaş,et al.  Determination of insulation thickness by means of exergy analysis in pipe insulation , 2012 .

[5]  Wan Ki Chow,et al.  Optimum insulation-thickness for thermal and freezing protection , 2005 .

[6]  Alireza Bahadori,et al.  A simple correlation for estimation of economic thickness of thermal insulation for process piping and equipment , 2010 .

[7]  Ahmet Z. Sahin,et al.  Maintaining uniform surface temperature along pipes by insulation , 2005 .

[8]  P. Lettieri,et al.  An introduction to heat transfer , 2007 .

[9]  Omer Kaynakli,et al.  A review of the economical and optimum thermal insulation thickness for building applications , 2012 .

[10]  Ali Keçebaş,et al.  Economic and environmental impacts of insulation in district heating pipelines , 2011 .

[11]  Abdullah Yildiz,et al.  ECONOMICAL AND ENVIRONMENTAL ANALYSES OF THERMAL INSULATION THICKNESS IN BUILDINGS , 2008 .

[12]  Y. Hwang,et al.  Simulation comparison of VAV and VRF air conditioning systems in an existing building for the cooling season , 2009 .

[13]  E. Bilgen,et al.  Thermo-economic optimization of hot water piping systems : A comparison study , 2006 .

[14]  G. M. Zaki,et al.  Optimization of Multilayer Thermal Insulation for Pipelines , 2000 .

[15]  İsmail Yabanova,et al.  The use of artificial neural network to evaluate insulation thickness and life cycle costs: Pipe insulation application , 2014 .

[16]  Omer Kaynakli,et al.  Economic thermal insulation thickness for pipes and ducts: A review study , 2014 .

[17]  Ahmet Z. Sahin,et al.  Optimal insulation of ducts in extraterrestrial applications , 2004 .

[18]  Muhammet Kayfeci,et al.  Determination of energy saving and optimum insulation thicknesses of the heating piping systems for different insulation materials , 2014 .

[19]  Mehmet Ali Alkan,et al.  Thermo-economic analysis of pipe insulation for district heating piping systems , 2011 .

[20]  Seo Young Kim,et al.  Indoor unit fault detector for a multi-split VRF system in heating mode , 2014 .