New Features of Coils 7.2. New Features of. Brand new refrigerants, improved speed and much more!

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1 Page 1 of 13 New Features of Brand new refrigerants, improved speed and much more! Index Summary... 2 New refrigerants: R407F and R417B... 2 Some more details about R407F... 4 Faster Design Algorithm and Results Exportation to Excel... 5 Changes in the Fins Corrugation and Tubes Corrugation behavior... 8 Split of the Printout File for better performances... 12

2 Page 2 of 13 Summary UNILAB SRL is proud to announce the availability of an exciting new release of its best selling software, UNILAB, now updated to version 7.2! This new release introduces two brand new refrigerants, R407F and R417B, and a 1000% faster design algorithm that will let you match a coil with your customer s requirements in just no time. It introduces also many improvements that will be covered in this document. New refrigerants: R407F and R417B Now that we are in the middle of the R22 phase-out, many companies are searching for a good replacement between the many retrofits available. R407F and R417B for example have been reported to be a good non-ozone depleting replacement for R22 in many commercial applications such as supermarket freezer cases, display cases, reach-in coolers, transport refrigeration and ice machines. Datasheets reports that using these new refrigerants you can actually save up to 15% in energy, 40% in CO2 emissions and 10% in operating costs. In addition, R407F is also well suited for new installations as a replacement for R404A, showing a significant reduction in their carbon footprint which results in less power consumption. UNILAB, which always keeps proactive and attentive about the refrigeration and HVAC global market, is proud to introduce those new retrofits into its newest release, 7.2. Engineers and technicians worldwide are now able to design new finned pack heat exchangers with R407F or R417B, compare the performances of these new refrigerants with old refrigerants at the same conditions, check the Selecting one of the these new refrigerants is very easy: you just have to open or create a new project in Direct Expansion, Condensing, or in any other modality that uses bi-phase fluids, and choose the refrigerant you want from the fluids menu. They are shown between the most used fluids for your convenience: Fig.1: The new refrigerants shown in the fluids list

3 140 C 160 C New Features of Coils 7.2 Page 3 of 13 All the many utilities of the program can benefit from these new fluids. The following example is a generated P-H graph of R407F: , ,0 R407F 10000,0-60 C -40 C -20 C 0 C 20 C 40 C 60 C 80 C 100 C 120 C 240 C 260 C 280 C 300 C 5000,0 180 C 200 C 220 C Pressure (kpa) 1000,0 500,0 100,0 50,0 10,0 0,0 250,0 500,0 750,0 1000,0 Enthalpy (kj/kg) Fig.2: The R407F Refrigerant s P-H Chart

4 Page 4 of 13 Some more details about R407F Chemical Name: Difluoromethane/Pentafluoroethane/Tetrafluoroethane Molecular Formula: CH2F2/CHF2CF3/CH2FCF3 Appearance: Colorless Molecular Weight: 82.1 Units English Si Bubble Point Temperature Atm kpa Dew Point Temperature Atm kpa Bubble Point Pressure (Psia) 1311 (kpa) Dew Point Pressure (Psia) 1144 (kpa) Critical Temperature F 82.6 C Critical Pressure (Psia) 4754 (kpa) Critical Volume (ft3/lb) (m3/kg) Critical Density 29.8 (lb/ft3) (kg/m3) Vapor Density Atm kpa Liquid Density (lb/ft3) 1117 (kg/m3) Liquid Heat Capacity 0.38 (Btu/lb F) 1.57 (KJ/kg K) Vapor Heat Capacity 0.28 (Btu/lb F) 1.18 (KJ/kg K) Heat of Vaporization 1 Atm kpa Liquid Thermal Conductivity (Btu/hr ft F) (mw/m K) Vapor Thermal Conductivity (Btu/hr ft F) 14,51 (mw/m K) Liquid Viscosity (lbm/ft hr) (upa.s) Vapor Viscosity (lbm/ft hr) (upa.s) Flammability Limits in Air (vol%) None * Ozone Depletion Potential (ODP) 0.0 ASHRAE Safety Group Classification A1/A1 Notes: * Based on ASHRAE Standard 34 with match ignition. All data are at 77 F (25 C) unless otherwise noted. Source: Honeywell Genetron Performax LT brochure

5 Page 5 of 13 Faster Design Algorithm and Results Exportation to Excel Another significant feature of is the Design algorithm, which perform a calculation of all the possible combinations of number of rows, circuits, fin spacing, etc. and then select the resulting coils with both the best performances and the lowest pressure drops. This feature has been redesigned so that now it is 1000% faster: in just a couple of seconds it calculates thousands of combinations and shows the best results. Let s perform an example. The initial conditions in verify mode are: Fig.3: The calculation conditions of the example Let s now switch to the design calculation, by clicking on the Design option on the top right corner of the calculation window: Fig.4: switching to the Design mode

6 Page 6 of 13 After pressing the Design option button, a new form will appear: Fig.4: The new form with the Design Parameters Here we can set all the parameters for the design at once: Required capacity Tolerance on the Required Capacity in percentage (both positive and negative) Maximum Pressure Drops Air Side Tolerance on the Maximum Pressure Drops Air Side in percentage Maximum Pressure Drops Fluid Side Tolerance on the Maximum Pressure Drops Fluid Side in percentage Supply Side: force to be on the Same Side or Automatic The new form shows both a Calculate button and an Ok button. The first perform the Design calculation, and the second closes the form so that it can be recalled later. Once customized the above parameters, we click on the Calculate button, and immediately a list of compatible coils is shown:

7 Page 7 of 13 Fig.5: The results of the Design calculation example Now it is possible to review the list, calculate (and customize) a specific coils or even export the whole list of coils on an Excel!

8 Page 8 of 13 Changes in the Fins Corrugation and Tubes Corrugation behavior UNILAB 7.2 introduces an important improvement regarding the factors influence on the calculation and the geometry characteristics. Up to version 7.1, the Fin Corrugation Factor was the only key for the program to understand if a fin was corrugated, windowed or louvered. For example a geometry with a fin corrugation factor between 1.15 and 1.35 was marked as Corrugated, from 1.35 to 1.45 was marked Windowed, and above Louvered. This behavior was clearly stated in the Geometry Details form. In the example screenshot below, the geometry has a Fin Corrugation Factor of 1.15 and the form shows it s Corrugated: Fig.6: The Geometry Details form in version 7.1 showing a sample geometry with a Fin Corrugation Factor of 1.15 Furthermore, changing the fin corrugation picture in the Geometry Details form would change the corresponding factors: From: To: Changes Factors: Fig.7: How Geometry Factors changes after selecting a different corrugation in UNILAB 7.1

9 Page 9 of 13 There was some situations where this relationship would prevent the user to see the geometry corrugation characteristics correctly showed when factors were changed, for example to simulate some treatments on the fins surface. To make this concept more clear, let s suppose we have a 25x22 geometry with a windowed surface. Its default Fin Corrugation Factor is 1.35, but the fins are painted with a special coating. To simulate the influence of this coating and perform a correct calculation, we have to reduce the Fin Corrugation Factor to The geometry is still a windowed one, but the program shows it s a corrugated because its Fin Corrugation Factor is between 1.15 and This behavior is clearly incorrect, and the same thing would happen to the tubes corrugations factors too. Now in version 7.2, this has been changed. The fin corrugation and the tubes corrugation characteristics are now parameters of the geometry, that can be saved and modified anytime independently from the factors used. The Geometry Details form behavior has changed too, and the above feature of changing the factors automatically after changing the corrugation characteristics, is not available anymore. But what if you need to change the fin corrugation characteristics of a geometry and you want to reflect the change in the factors, using the default values suggested by UNILAB? Let s suppose we want to change the _C_S geometry. It has corrugated fins and smooth tubes: Fig.8: The sample geometry before changing fin corrugation

10 Page 10 of 13 Now we change the fin corrugation to Windowed, and the button Synchronize Factors appears: Fig.9: After changing the fin corrugation, the Synchronize Factors button appears The factors won t be changed, until we click on the Synchronize Factors button. In fact clicking on the button the program will overwrite the factors already present in the geometry, otherwise the previous factor will be kept. After clicking on the button, you will be prompted if you want to overwrite the previous factor: Fig.10: After clicking on the button, the program asks to overwrite the factors.

11 Page 11 of 13 Let s click on Yes so that the new factors will be applied to the geometry: Fig.11: The new factors applied after synchronizing One important reason of this change regards the Certification process (both AHRI and EUROVENT): certification issuers requires the printout sheets of to clearly state what fins and tubes typology are under certification process, regardless from the factors used. To correctly accomplish this task, the separation of the factors from the corrugation characteristics was mandatory. The user also can benefit too from this important change, because now the geometry designation is more coherent to the coils under calculation, and the corrugation characteristics are completely unlinked to the factors used to trim the calculation.

12 Page 12 of 13 Split of the Printout File for better performances In UNILAB 7.1, to improve the software s performances, we have done some big improvements in the printout system. All the printout pages of all the calculation modalities were stored in one QTX file, accessible from PageBuilder: Fig.12: The QTX file (and the related QTD file) storing all the printout pages of all the calculation modalities This file was extremely big, and the program used to be slowed down when loading this file. In the latest versions of, we have divided this file into many smaller QTX files: Fig.13: The new and smaller QTX files (and the related QTD files) that now 7.2 uses Since we have divided the printout file C6Printing.qtx into many smaller files, the C6Printing.qtx file is now deprecated, and any change made with PageBuilder on this file would not be shown on UNILAB 7.2.

13 Page 13 of 13 The correct procedure to customize the printout sheets of UNILAB 7.2 is: 1. From PageBuilder, open the C6Printing.qtx file (or click on the Coils 6.0 icon into the list of customizable applications) 2. Modify any page as needed 3. Go to the Tools menu and click on the Extract Files for Coils, like shown below: Fig.14: The Extract files for tool, to split the C6Printing.qtx file into smaller files used by UNILAB 7.2 The program will split the C6Printing.qtx file so that 7.2 will use the new customized printout sheets immediately. Contact us to download the new version of PageBuilder. Note: please remember not to change the structure of the files, especially modules and sections.