Forced-Circulation Air-Cooling and Air-Heating Coils

Transcription

1 AHRI Sandard (Formerly ARI Sandard ) 001 Sandard or Forced-Circulaion Air-Cooling and Air-Heaing Coils

2 WITH AEUM 3, Forced-Circulaion Air-Heaing and Air-Cooling Coils June 011 AHRI Sandard wih Addendum 3, Forced-Circulaion Air-Heaing and Air-Cooling Coils, is comprised o only he shaded porions shown. The June 011 Addendum 3 has been incorporaed ino he already published 001 version o AHRI Sandard 410 o avoid conusion. Paricular addiions (shown shaded in he sandard), deleions (shown wih a srikehrough and shaded in he sandard), and correcions (shown shaded in he sandard) are as ollows: 1. In he ollowing secions propylene was added Ceriied Raings iem c Table o Conens Figure 16 Secions o 3.1.a o a o Table 1 Table Secions o 3.3. o 5..7 o o o o o o o o 6.. Equaions (7b), (7c), (8a), (9a), (10a), igure beore (15b), (17b), (18b), (19b), (0b), and (4a) o (Form 410-7) Secions o o 7.1 K, l, m, n o 8.1 (c pg ), ('), (Q gst ), (V g ), (w), and (x g ) o 8.. (a) and (g) Figures 1, 13, 14, 15 and 16 Air-Condiioning, Heaing and Rerigeraion Insiue 111 Wilson Blvd, Suie 500 Arlingon, VA 01

3 WITH AEUM, Forced-Circulaion Air-Heaing and Air-Cooling Coils May 005 AHRI Sandard wih Addendum, Forced-Circulaion Air-Heaing and Air-Cooling Coils, is comprised o only he shaded porions shown. The May 005 Addendum has been incorporaed ino he already published 001 version o AHRI Sandard 410 o avoid conusion. Paricular addiions (shown shaded in he sandard), deleions (shown wih a srikehrough and shaded in he sandard), and correcions (shown shaded in he sandard) are as ollows: 1. In Secion he las senence was replaced wih he ollowing : I he calculaed capaciy is less han 97.5%, new raings shall be calculaed. Air-Condiioning, Heaing and Rerigeraion Insiue 111 Wilson Blvd, Suie 500 Arlingon, VA 01

4 WITH AEUM 1, Forced-Circulaion Air-Heaing and Air-Cooling Coils May 00 AHRI Sandard wih Addendum 1, Forced-Circulaion Air-Heaing and Air-Cooling Coils, is comprised o only he shaded porions shown. The May 00 Addendum 1 has been incorporaed ino he already published 001 version o AHRI Sandard 410 o avoid conusion. Paricular addiions (shown shaded in he sandard), deleions (shown wih a srikehrough and shaded in he sandard), and correcions (shown shaded in he sandard) are as ollows: 1. In Secion he second senence was replaced wih he ollowing: Published values o air-side pressure drop, under es, shall no be exceeded by more han 10%, or 0.05 in HO [1.5 Pa], whichever is greaer. Air-Condiioning, Heaing and Rerigeraion Insiue 111 Wilson Blvd, Suie 500 Arlingon, VA 01

5 IMPORTAT SAFETY ISCLAIMER AHRI does no se saey sandards and does no ceriy or guaranee he saey o any producs, componens or sysems designed, esed, raed, insalled or operaed in accordance wih naionally recognized saey sandards and code requiremens appropriae or producs covered by his sandard/guideline. AHRI uses is bes eors o develop sandards/guidelines employing sae-o-he-ar and acceped indusry pracices. AHRI does no ceriy or guaranee ha ess conduced under is sandards/guidelines will be non-hazardous or ree rom risk. AHRI CERTIFICATIO PROGRAM PROVISIOS Scope o he Ceriicaion Program The Ceriicaion Program includes Forced-Circulaion Air-Cooling Coils or applicaion under non-rosing condiions, and Forced-Circulaion Air-Heaing Coils, as deined in Secion 3 o he sandard. Coils Included. This program applies only o coils inended: a. For ield insallaion (buil-up sysems) b. For use in cenral saion air-condiioning unis c. For use in cenral saion heaing or heaing and venilaing unis Exclusion. I does no include: a. Coils sold o original equipmen manuacurers or inclusion in packaged unis b. Coils insalled in packaged air-condiioning or heaing unis by he manuacurer c. Special coils: Coils o in or ube maerial o special coniguraion no having caaloged perormance daa oe: For he purpose o his program, a packaged uni is an assembly o componens including coil(s) whose raing is based on a es o he complee assembly. Ceriied Raings The ollowing Ceriicaion Program raings are veriied by es: a. Average oal cooling or heaing capaciy, Bu/h [W] b. Air pressure drop hrough coil a sandard air densiy, in H O [kpa] c. Waer, or aqueous ehylene glycol, or aqueous propylene glycol soluions pressure drop hrough coil (including headers) a average luid densiy, o luid [m o luid] oe: This sandard supersedes ARI Sandard Price $0.00 (M) $40.00 (M) Prined in U.S.A. Copyrigh 001, by Air-Condiioning, Heaing and Rerigeraion Insiue Regisered Unied Saes Paen and Trademark Oice

6

7 TABLE OF COTETS SECTIO PAGE Secion 1. Purpose... 1 Secion. Scope... 1 Secion 3. einiions... 1 Secion 4. Classiicaions... 4 Secion 5. Tes Requiremens... 1 Secion 6. Raing Requiremens Secion 7. Minimum aa Requiremens or Published Raings Secion 8. Symbols and Unis Secion 9. Reerence Properies and Conversion Facors Secion 10. Marking and ameplae aa Secion 11. Conormance Condiions TABLES Table 1. Range o Sandard Raing Condiions... Table. Required Laboraory Tess... 1 Table 3. Meal Thermal Conduciviies... 7 Table 4. Conversion Facors... 38

8 FIGURES Figure 1. Figure. Combined Air Film and Meal Thermal Resisance or ry Surace vs. Air Film Thermal Resisance or ry Surace Toal Meal Thermal Resisance o Fin and Tube Assembly Based on Toal Surace Eeciveness Figure 3. Raing aa or Seam Coils Figure 4. Raing aa or Ho or Cold Waer Sensible Hea Coils... 4 Figure 5. Raing aa or Cold Waer Cooling and ehumidiying Coils Figure 6. Raing aa or Volaile Rerigeran Cooling and ehumidiying Coils Figure 7. Temperaure Correcion Facor or Waer Pressure rop Figure 8. Air-Side Hea Transer Coeicien Muliplier or We Surace Figure 9. Surace Temperaure Char or Air Cooling and ehumidiying Coil Applicaion Figure 10. Eiciency o Annular Fins o Consan Thickness Figure 11. Eiciency o Annular Fins o Consan Area or Hea Flow and Spiral Fins Figure 1. eerminaion o RaW, r and q Figure 13. Crosslow Air-Side Eeciveness Figure 14. Cross-Counerlow Air-Side Eeciveness... 5 Figure 15. Counerlow Air-Side Eeciveness Figure 16. Aqueous Ehylene Glycol and Aqueous Propylene Glycol Soluions Perormance or Smooh Inernal Tube Wall Coils Figure 17. Smooh Inernal Tube Wall Hea Transer Facor or Waer APPEICES Appendix A. Reerences ormaive Appendix B. Reerences Inormaive... 57

9 FORCE-CIRCULATIO AIR-COOLIG A AIR-HEATIG COILS Secion 1. Purpose 1.1 Purpose. The purpose o his sandard is o esablish or Forced-Circulaion Air-Cooling and Air-Heaing Coils: deiniions; classiicaions; es requiremens; raing requiremens; minimum daa requiremens or Published Raings; symbols and unis; reerence properies and conversion acors; marking and nameplae daa; and conormance condiions Inen. This sandard is inended or he guidance o he indusry, including manuacurers, engineers, insallers, conracors and users Review and Amendmen. This sandard is subjec o review and amendmen as echnology advances. Secion. Scope.1 Scope. This sandard applies o Forced-Circulaion Air-Cooling and Air-Heaing Coils, as deined in Secion 3 and classiied in Secion 4 o his sandard, and or applicaion under non-rosing condiions. This sandard documens a undamenal means or esablishing coil perormance by exension o laboraory es daa o oher operaing condiions and oher coil sizes and row dephs. Secion 3. einiions All erms in his documen shall ollow he sandard indusry deiniions in he curren ediion o ASHRAE Terminology o Heaing, Venilaion, Air Condiioning and Rerigeraion unless oherwise deined in his secion. 3.1 Coil Line. For he purpose o his sandard, a coil line is deined as having he ollowing in common: a. Fluid (volaile rerigeran, waer, seam, or aqueous ehylene glycol, or aqueous propylene glycol soluions) b. Tube size, spacing, arrangemen (parallel or saggered) or inernal consrucion c. Fin coniguraion (no spacing) Examples o coil lines are: a. Aqueous Ehylene Glycol or Aqueous Propylene Glycol Soluions. I condiions b and c o 3.1 are saisied, he ollowing are ypes which may be par o one line: 1. Coninuous circui ype. Sel-draining ype 3. Cleanable ype 1

10 b. Seam isribuing. c. Seam Single-Tube. d. Volaile Rerigeran. irec expansion coil wih low conrolled by he expansion valve. e. Waer. I condiions b and c o 3.1 are saisied, he ollowing are ypes which may be par o one line: 1. Coninuous circui ype. Sel-draining ype 3. Cleanable ype 3. Cooling Capaciy. The capaciy associaed wih he change in air enhalpy which includes boh he Laen and Sensible Capaciies expressed in Bu/h [W] Laen Capaciy. Capaciy associaed wih a change in humidiy raio. 3.. Sensible Capaciy. Capaciy associaed wih a change in dry-bulb emperaure. 3.3 Forced-Circulaion Air Coil. A coil or use in an air sream whose circulaion is caused by a dierence in pressure produced by a an or blower Forced-Circulaion Air-Cooling Coil. A hea exchanger, wih or wihou exended suraces, hrough which eiher cold waer, cold aqueous ehylene glycol or aqueous propylene glycol soluions, or volaile rerigeran is circulaed, or he purpose o oal cooling (sensible cooling plus laen cooling) o a orced-circulaion air sream. Table 1. Range o Sandard Raing Condiions Cooling Coils Heaing Coils Iem Volaile Rerigeran Cold Waer Cold Ehylene and Propylene Glycol Soluion Seam Ho Waer Ho Ehylene and Propylene Glycol Soluion Sandard air ace velociy, sd. /min [sd. m/s] 00 o 800 [1 o 4] 00 o 800 [1 o 4] 00 o 800 [1 o 4] 00 o 1,500 [1 o 8] 00 o 1,500 [1 o 8] 00 o 1,500 [1 o 8] Enering air dry-bulb emp., F [C] 65 o 100 [18 o 38] 65 o 100 [18 o 38] 65 o 100 [18 o 38] -0 o 100 [-9 o 38] 0.0 o 100 [-18 o 38] -0 o 100 [-9 o 38] Enering air we-bulb 60 o o o 85 emp., F [C] [16 o 9] [16 o 9] [16 o 9] Tube-Side luid velociy, sd. /s [sd. m/s] o 8.0 [0.3 o.4] 1.0 o 6.0 [0.3 o 1.8] o 8.0 [0.1 o o 6.0 [0.1 o 1.8] Enering luid emp., F [C] 35 o 65 [1.7 o 18] 0.0 o 90 [-18 o 3] 10 o 50 [49 o 11] 0.0 o 00 [-18 o 93] Sauraed sucion rerigeran emp. a coil oule, F [C] 30 o 55 [-1.1 o 13]

11 Table 1. Range o Sandard Raing Condiions Cooling Coils Heaing Coils Minimum sucion vapor superhea a coil oule, F [C] 6.0 [3.3] Seam pressure a coil inle, psig [kpa gage].0 o 50.0 [14 o 173] Maximum superhea in 50 seam a coil inle, F [C] [8] Concenraion by mass, % 10 o o 60 Minimum in surace emperaure, F [C] > 3 [> 0.0] > 3 [> 0.0] > 3 [> 0.0] > 3 [> 0.0] > 3 [> 0.0] > 3 [> 0.0] Minimum ube wall surace emperaure, F [C] 1 > 3 [> 0.0] > 3 [> 0.0] > ehylene glycol and propylene glycol sol. reeze poin > 3 [> 0.0] > 3 [> 0.0] > ehylene glycol and propylene glycol sol. reeze poin On lower limi, Re shall exceed 3100 a wm. Prediced perormance and acual perormance in he waer velociy range below he ube-side luid velociy lised above is expeced o show variaions in excess o currenly acceped olerances or he ollowing reasons: 1) Applicaion o coils a low velociy can lead o excessive ouling. ) Applicaion o coils a low velociy can lead o possible air enrapmen. 3) ierences in coil design/ype aec he variaion in low Re hea ranser coeicien. On lower limi, Re shall exceed 700 a gm. oe: umbers in [ ] are in SI Unis 3.3. Forced-Circulaion Air-Heaing Coil. A hea exchanger, wih or wihou exended suraces, hrough which eiher ho waer, ho aqueous ehylene glycol or aqueous propylene glycol soluions, or seam is circulaed or he purpose o sensible heaing o a orced-circulaion air sream. 3.4 Heaing Capaciy. The capaciy associaed wih he change in dry-bulb emperaure expressed in Bu/h [W]. 3.5 Laboraory Tess. Tess conduced by a manuacurer on represenaive coils o deermine basic hea ranser and pressure drop characerisics ha shall be used in developing Published Raings. 3.6 Published Raings. A compilaion o he assigned values o hose perormance characerisics, under saed raing condiions, by which a coil may be chosen o i is applicaion. These values apply o all coils o like nominal size and ype (ideniicaion) produced by he same manuacurer. As used herein, he erm Published Raings includes he raings o all perormance characerisics published in speciicaions, adverising or oher lieraure conrolled by he manuacurer or available hrough an auomaed raing/selecion compuer procedure Applicaion Raings. Raings deermined a condiions ouside he range o sandard raing condiions Sandard Raings. Raings wihin he range o sandard raing condiions (Table 1) and which are accurae represenaions o es daa. 3.7 "Shall" or "Should". Shall or "should" shall be inerpreed as ollows: 3

12 3.7.1 Shall. Where "shall" or "shall no" is used or a provision speciied, ha provision is mandaory i compliance wih he sandard is claimed Should. "Should" is used o indicae provisions which are no mandaory bu which are desirable as good pracice. 3.8 Sandard Air. Air weighing lb/ 3 [1. kg/m 3 ] which approximaes dry air a 70F [1C] and a a baromeric pressure o 9.9 in Hg [101.3 kpa]. 3.9 Sandard Coil Orienaion. The sandard coil posiion is ha o horizonal ubes and verical coil ace wih horizonal airlow Tes Series. A group o relaed ess perormed on he same es coil Turbulaors. Mechanical devices inside ubes used o increase urbulence o luids. Secion 4. Classiicaions 4.1 Coil Surace imensions, Terminology and Surace Calculaions Tube Arrangemens and Types o Fin Combinaions Saggered ubes wih: a. Coninuous la plae ins b. Coninuous coniguraed plae ins c. Crimped spiral ins d. Smooh spiral ins e. Fla plae ins on individually-inned ube. Coniguraed plae ins on individually-inned ube Parallel (in-line) ubes wih: a. Coninuous la plae ins b. Coninuous coniguraed plae ins c. Crimped spiral ins d. Smooh spiral ins e. Fla plae ins on individually-inned ube. Coniguraed plae ins on individually-inned ube 4.1. imensions, Terminology and Fin Eiciency Calculaions. (oe: Equaions in [ ] are in SI Unis) In he igures shown in , and , H applies as shown wheher channel langes are urned inward or ouward. Where an opion is oered in he measuremen o any dimension, he same basis shall be used o deermine raing daa as used in he evaluaion o es resuls. 4

13 imensions L and Ld or a coniguraed in are deermined, a he opion o he manuacurer, rom he blank in shee size prior o orming he coniguraion providing no edge rimming is perormed aer orming or rom he inished in size aer orming Saggered ubes and parallel (in-line) ubes (as shown below) wih coninuous la plae or coniguraed plae ins Saggered ubes (as shown below) wih smooh or crimped spiral ins or wih la plae or coniguraed plae ins on individually-inned ube. Air bales shown are o be considered opional and H may be he disance beween channels as shown in

14 Parallel (in-line) ubes (as shown below) wih la plae or coniguraed plae in on individuallyinned ube or wih smooh or crimped spiral ins Fin-Tube Assemblies. a. Plae ins wih collars ouching adjacen in Fin eiciency calculaions: x e L L d 0.5 or coninuous plae in 6

15 7 0.5 d e L L x or individually-inned ube o b Y x x e x b w From he curve o a Y k w 0.5 a Y k w or various values o xe/xb, deermine (Figure 10) b. Plae ins wih collars no ouching adjacen in Fin eiciency calculaions same as or plae ins wih collars ouching adjacen in, excep as ollows: o b Y x c. Plae ins wihou collars

16 Fin eiciency calculaions same as or plae ins wih collars ouching adjacen in, excep as ollows: xb o d. Smooh spiral ins Fin eiciency calculaions xe o xb w x e xb 8

17 9 From he curve o r a Y k w 0.5 r a Y k w or various values o xe/xb, deermine (Figure 11) e. Crimped spiral ins Fin eiciency calculaions same as or smooh spiral ins excep: o n n r Y Y Equaions or eermining Coil Areas and Surace Raio. (oe: Equaions in [ ] are in SI Unis) eerminaion o As and Ap a. Coninuous plae ins or saggered and parallel ube arrangemens c h o o h d s L Y Y L L A c h o o h d L Y Y L L c o o p L Y L A c o o L Y L

18 10 b. Smooh spiral ins e o s Y A e o Y r o p Y L A r o Y L c. Crimped spiral ins e n o n n s Y A e n o n n Y r o p Y L A r o Y L d. Plae ins on individually-inned ube d o d s Y L L Y L L A d o d Y L L Y L L o p Y L Y A o Y L Y eerminaion o A, A o, A i, B, A ix, p, b and L e (all cases) 144 HL A HL p s o A A A i i L A i L

19 B A o / A i A ix x10 7 i c i c / p c b p ih 1 L e L s L L s p p L eb eb b b 11

20 Table. Required Laboraory Tess Type o Coil One Row Two Rows Three Rows or More In-Line Tubes, All Oher Coniguraions Fla Plae Fins Seam (isribuing ube) Tes Tes o Tes 1 o Tes 1 Seam (Single ube) o Tes o Tes o Tes o Tes Ho Waer o Tes 3 o Tes 4 o Tes 3 o Tes 3 All Cooling Tes 5 Tes Tes 5 Tes our-row, or iverow, or six-row coil Aqueous Ehylene Glycol and Aqueous Propylene Glycol Soluions Tes same coil as used or sensible cooling ess Where o Tes is indicaed, he manuacurer may, a his opion, perorm ess o esablish perormance acors, in which case noes 1-4 below do no apply: 1 3 Seam raings may be calculaed using daa rom one-row ess. The same seam raings may be used as deermined or seam disribuing ube coil o same surace geomery. The overall hermal resisance, R, may be deermined by eiher o he ollowing procedures: (a) R a is deermined rom seam coil ess, assuming a seam-side hea ranser coeicien, v, o 000 Bu /(h F) [11360 W/(m C)]. One-row seam coil ess shall be used o deermine R a or one-row ho waer coils. One-row or wo-row seam coil ess may be used o deermine R a or wo-row ho waer coils. (b) R a is deermined rom sensible cooling ess. One-row sensible cooling ess shall be used o deermine R a or one-row ho waer coils. One-row or wo-row sensible cooling ess may be used o deermine R a or wo- or more-row ho waer coils. (c) For eiher (a) or (b) above, i is necessary o conduc isohermal waer pressure drop ess per The air-side hermal resisance, R a, may be deermined as in 3 excep ha wo-row coils shall be used. A complee se o ess is no required, provided he air-side hea ranser coeiciens, a, as deermined rom a sensible cooling waer es series, are wihin.5% o hose rom our- or more-row ess. I his agreemen exiss or a one-row coil, no es is required or a wo-row coil. Secion 5. Tes Requiremens 5.1 Mehod or Laboraory Tess o Tesing or Raing. Forced-Circulaion Air-Cooling and Air-Heaing Coils shall be esed in accordance wih ASI/ASHRAE Sandard 33. 1

21 5. Tes Coils and Laboraory Tess imensional Requiremens. All cooling and heaing coil Laboraory Tess shall be conduced wih a represenaive coil having a ace area o o 10 [0.19 o 0.93 m ]. 5.. Required Laboraory Tess. See Table Turbulaors. I urbulaors are oered as an opion o increase he hea ranser coeicien o he luid inside he coil ubes, only one coil need be esed o esablish he correlaion beween he ube-side hea ranser coeiciens, wih and wihou urbulaors Fin Spacings. Air ilm hea ranser coeiciens and air-side pressure drops or various in spacings may be deermined wihou esing provided ha he inerpolaed in spacing is beween wo spacings previously esed which are no more han 8 ins/in [315 ins/m] apar Opional Changes rom Tes Coil Changes Requiring o Tes. Aer esablishing he original Sandard Raings, one or more o he ollowing changes can be made or oered as an opion in a coil line wihou changing Published Raings, provided ha he calculaed inluence o any or all o hese changes does no reduce he capaciy o less han 97.5% o he corresponding Sandard Raings. a. Copper in hickness may be decreased up o 30% below aluminum in hickness b. Fin hickness increase c. Tube wall hickness beween and in [0.406 and 1.54 mm] d. Tube maerial, limied o ypes normally used in comor air-condiioning, such as copper, red brass, admiraly meal, aluminum and cupro-nickel I he calculaed capaciy is less han 97.5%, new raings shall be calculaed and submied o AHRI or approval Changes Requiring Tess. Aer esablishing he original Sandard Raings, one or more o he ollowing changes can be made or oered as an opion in one or more coil lines wih he same surace geomery, provided a sensible cooling or heaing Tes Series o our ace velociies is run and he es capaciies are no less han 97.5% o he corresponding Sandard Raings: a. Fin maerial oher han copper b. Mehod o bonding c. Tube wall hickness ouside he range o c d. Tube maerial oher han as provided in d e. Fin hickness decrease I he es capaciies are less han 97.5% o Sandard Raings, or i oher changes such as ube O, ube spacing, in coniguraion or ube arrangemen are made, a complee se o Laboraory Tess shall be run and Published Raings shall be changed accordingly. I he pressure drops are greaer han 105% o Sandard Raings, a series o pressure drop ess shall be run and raings shall be published accordingly Rerigeran. Separae Laboraory Tess mus be conduced or each rerigeran covered by volaile rerigeran coil raings. 13

22 5..7 Aqueous Ehylene Glycol or Aqueous Propylene Glycol Soluions Coils. These coils shall have separae Laboraory Tess. Aqueous ehylene glycol or aqueous propylene glycol soluion raings shall no be applied o oher luids Coil Orienaions oher han Sandard. Inormaion should be available or deermining cooling and dehumidiying coil Applicaion Raings or coil orienaions oher han he sandard orienaion (see 3.9). Any such raing shall be subsaniaed by adequae addiional Laboraory Tess. 5.3 Hea Transer Raing Variables o be eermined by Laboraory Tess Range o Hea Transer Variables. The range o hea ranser variables over which raings may be applied shall be limied sricly o he range included in he Laboraory Tess; values shall no be exrapolaed ouside he range covered in he Laboraory Tess excep or he ollowing: a. Iniial air-o-ube side luid emperaure dierence or all coils b. Inle seam pressure or seam coils c. Fluid velociy or waer and aqueous ehylene glycol or aqueous propylene glycol soluion coils d. Fluid emperaures or waer and aqueous ehylene glycol or aqueous propylene glycol soluion coils e. Fluid concenraions or aqueous ehylene glycol or aqueous propylene glycol soluion coils 5.3. The hea ranser variables or he various coil applicaions covered by his sandard, which shall be evaluaed or heir eec on hermal perormance by conducing Laboraory Tess, are described under Minimum Requiremens or Laboraory Tess General Scope Air Velociy. All o he ollowing Tes Series or speciic coil applicaions, excep under , and shall be made wih a leas our dieren sandard air ace velociies, covering he complee raing range o air speed in approximaely equally spaced velociy incremens on a logarihmic scale Fluid Velociy. For any es wih waer coils excep under and 5.4.7, a single luid velociy should be used in he range rom 3 o 6 /s [0.9 o 1.8 m/s] Air-Side Pressure rop. The coil air-side pressure drop or all dry and we surace ess shall be recorded per ASI/ASHRAE Sandard Seam Heaing Coils. The purpose o his Tes Series is o deermine he variaion in he overall hea ranser resisance, R, wih he sandard air ace velociy, V a, and o deermine he seam pressure drop hrough he coil Seam Pressure. For any es, he inle seam pressure shall be o 10 psig [14 o 69 kpa gage] wih an inle seam superhea as speciied in ASI/ASHRAE Sandard Waer or Aqueous Ehylene Glycol or Aqueous Propylene Glycol Soluions Sensible Cooling Coils. To assure compleely dry air-side surace, he enering luid emperaure, w1 or g1, or all ess shall be equal o or greaer han he enering air dew poin emperaure, 1dp Waer Coil wih Smooh Inernal Tube Walls. For coil designs wih smooh inernal ube walls, he waer ilm hea ranser coeicien, w, is iniially known and shall be calculaed rom curve i Equaion (8)

23 shown in Figure 17. Only a single Tes Series is required or he purpose o deermining he variaion in he dry surace air ilm hea ranser coeicien, a, wih sandard air ace velociy, V a. (See and ) Waer Coils wih Tube esigns Oher han Smooh Inernal Tube Walls. For coils using ube designs wih inernal ins, urbulaors, ec., boh he waer and air ilm hea ranser coeiciens, as a uncion o he respecive luid mass low rae, are unknown. Two Tes Series are required or his ype o coil design Tes Series umber 1. A single Tes Series, as described in , shall irs be conduced on a hea ranser surace whose design and arrangemen are he same in all respecs o he raed design excep ha smooh inernal ube walls are used Tes Series umber. A single Tes Series shall be conduced on a hea ranser surace whose design and arrangemen are he same as he raed design including inernal ube ype geomery. A leas our ess wih dieren waer velociies are required, covering he complee raing range o waer velociy in approximaely equally spaced incremens on a logarihmic scale. For any es he sandard air ace velociy may range rom 00 o 800 sd. /min [1 o 4 sd. m/s]. Use o high sandard air ace velociies and close in spacings is recommended or accuracy reasons. For his Tes Series, knowing he air ilm hea ranser coeiciens, a, deermined under , he waer ilm hea ranser coeiciens, w, may be deermined as a uncion o waer velociy and waer emperaure. The values o w, hus deermined, shall be used boh or analysis o Laboraory Tess and or raing purposes in lieu o waer perormance or smooh ube coils rom Figure Aqueous Ehylene Glycol or Aqueous Propylene Glycol Soluion Coils wih Smooh Inernal Tube Walls. Two series o ess shall be conduced Tes Series umber 1. A single Tes Series wih waer, as described in , shall irs be conduced on a hea ranser surace whose design and arrangemen are he same in all respecs o he raed design Tes Series umber. Tes he same coil as in Tes Series 1 excep ha he ube side luid shall be aqueous ehylene glycol or aqueous propylene glycol soluion, 50% 5% by mass, a emperaures beween 45F [7.C] and 100F [37.8C]. A minimum o eleven ess shall be conduced o adequaely deine a Colburn j-acor versus Re curve as illusraed in Figure 16. Four es poins shall be below 100 Re, hree es poins beween 100 and 7000 Re and our es poins above 7000 Re. All ess shall be conduced a one sandard air ace velociy beween 00 and 800 sd. /min [1 o 4 sd. m/s]. Use o high air velociies and close in spacings is recommended or accuracy reasons. For his Tes Series, wih he air-side hea ranser coeiciens, a, deermined under , he aqueous ehylene glycol or aqueous propylene glycol soluion ilm hea ranser coeicien, g, may be deermined. Using he luid properies in he ASHRAE Handbook-Fundamenals, he Colburn j- acor and Re can be calculaed and ploed as illusraed in Figure 16. The curve(s) so deined by he es poins shall be used or ube-side raing o aqueous ehylene glycol and aqueous propylene glycol soluion coils. 15

24 The above shall be conduced using a base coil wih L s / i raio beween 70 and 90. Raings or he range o Re beween 700 and 7000 shall be based upon he L s / i raio o he minus 0.4 power in he laminar low region as shown in Figure 16. A second coil may be esed a a dieren lengh and wih a minimum o our es poins a Re below 100 and hree es poins beween 100 and The L s / i exponen so deermined (laminar region) may hen be used or raing purposes. The las hree poins are used o more clearly deine he ransiion region. Properies o pure aqueous ehylene glycol and aqueous propylene glycol soluions are represenaive o mos sandard indusrial inhibied aqueous ehylene glycol soluions, bu do no apply o auomoive radiaor anireeze soluions Aqueous Ehylene Glycol and Aqueous Propylene Glycol Soluion Coils wih Tube esigns Oher Than Smooh Inernal Tube Walls. Two Tes Series shall be conduced Tes Series umber 1. Conduc ess wih waer idenical o hose in Tes Series umber. Proceed idenically as in excep ha he coil ubes shall include he inernal ins, urbulaors, ec. When posiive boundary layer inerrupers (such as closely spaced wire urbulaors or inernal ribs a righ angle o low axis, ec.) are used, he L s / i erm will no aec he hea ranser coeicien and only he base coil ess are required Ho Waer, or Aqueous Ehylene Glycol, or Aqueous Propylene Glycol Soluion Heaing Coils. Tess on ho waer, or aqueous ehylene glycol, or aqueous propylene glycol soluion heaing coils are no required (see 5..). Should any be esed, he enering luid emperaure, w1 or g1, shall be 180F [8.C] or higher and he enering air dry-bulb emperaure, 1db, shall no exceed 100F [37.8C]. The purpose and minimum esing are he same as given in and or smooh inernal ubes and oher ube designs, respecively Cold Waer Cooling and ehumidiying Coils. Two Tes Series shall be conduced ry Surace Sensible Hea Tess. The purpose and minimum esing are idenical wih hose in and or smooh ubes and oher ube designs, respecively We (ehumidiying) Surace Tess. The same es coil used or he procedure under shall be employed or hese ess Purpose. The purpose o his Tes Series is o esablish wheher, under we surace operaing condiions, any adjusmens are required in he air ilm hea ranser coeiciens, a, as deermined or dry surace ess under These adjusmens may, or may no, be required, depending upon he paricular design and arrangemen o he hea ranser surace. Also, he we surace air-side pressure drop is esablished by his Tes Series Surace Condiion. To deermine air ilm hea ranser coeiciens, a, and air-side pressure drop under compleely we surace condiions, each es shall be conduced wih he enire air-side surace acively condensing moisure. This operaing condiion exiss when he airside surace emperaure, a all locaions hroughou he coil, is below he enering air dew poin emperaure. 16

25 Range o Variables. For each es, he range in each o he ollowing design variables shall all wihin he limis lised below: w1 = Enering waer emperaure: 35 o 55F [1.7 o 1.8C] 1db - 1wb = Enering we-bulb depression 6.0F [3.3C] q s /q = Air sensible hea raio 0.75 wb - w1 5.0 F [.8C] Volaile Rerigeran Cooling and ehumidiying Coils. A complee Tes Series, as oulined below, shall be run wih each volaile ype rerigeran or which ess are required (see 5..6). Three series o ess shall be run on he same prooype coil or coils ry Surace Tess. Using cold waer, he irs series o ess shall be conduced as oulined under This requiremen may be deleed i ess under were previously compleed We Surace Tes. Using cold waer, a second series o ess shall be conduced as oulined under This requiremen may be deleed i ess under were previously compleed Volaile Rerigeran Tess. Using volaile rerigeran, he hird series o ess shall be conduced wih a leas wo dieren lenghs o rerigeran circuis or a given coil: a. A circui closely approximaing he maximum equivalen lengh used in he line o raed coils b. A circui whose lengh is no greaer han one-hird o he maximum equivalen lengh used in he line o raed coils For each o he wo rerigeran circui lenghs, a minimum o our ess are required. These are o cover he complee range o rerigeran loading per circui in approximaely equal incremens o capaciy on a logarihmic scale, and conduced wih a consan liquid emperaure in he range o 108 o 11F [4. o 44.4C] enering he conrol device and up o 55F [1.8C] sauraed coil oule rerigeran emperaure Evaluaion. The above eigh ess shall serve o evaluae he eecs o rerigeran loading per circui on boh he coil circui sauraed rerigeran pressure drop and he rerigeran evaporaing ilm hea ranser coeicien General Recommendaions. For any es, he sandard air ace velociy, V a, may range rom 00 o 800 sd. /min [1 o 4 sd. m/s]. The surace shall be operaed eiher compleely dry or compleely we in order o simpliy he daa reducion procedure Oule Superhea. Rerigeran oule vapor superhea, or any es, is o be mainained per ASI/ASHRAE Sandard Isohermal Waer Pressure rop For All Waer Coils. For each waer coil esed, he waer pressure drop hrough he coil shall be deermined under isohermal operaing condiions. Tess shall be made wih a leas our dieren waer velociies as speciied in Isohermal Pressure rop or Ehylene Glycol or Aqueous Propylene Glycol Soluion Coils. For each ehylene or propylene glycol soluion coil esed, he pressure drop hrough he coil shall be deermined under isohermal operaing condiions. Conduc a leas our ess a Re below 1000 and a leas our ess a Re above To 17

26 complee he pressure drop curve, exrapolae he wo resuling daa curves o ind he inersecion in he 1000 o 4000 Re region. Addiional ess may be run in he 1000 o 4000 Re region o complee he pressure drop curve. Secion 6. Raing Requiremens 6.1 Raings. Raings or Forced-Circulaion Air-Cooling and Air-Heaing Coils consis o Sandard Raings and Applicaion Raings used in he selecion or applicaion o coils. They are usually given or a range o condiions encounered in pracice, so ha he raing a any desired condiion may be seleced direcly or by inerpolaion Raings shall include pressure drop daa and perormance characerisics produced under speciied condiions, or means or calculaing speciic coil requiremens Raings may be presened in he orm o curves, ables, chars or auomaed raing/selecion compuer procedures Raings shall be developed using basic perormance characerisics obained rom Laboraory Tess in accordance wih his sandard. 6. Hea Transer Equaions or Laboraory Tes Reducion and or Raings. The iniial es daa reducion procedure and calculaions or he deerminaion o: a. Boh luid low raes b. The average or raed sensible and/or oal hea ranser capaciy c. Enering and leaving luid condiions d. Boh luid pressure drops are given in ASI/ASHRAE Sandard 33 boh or air sensible heaing or cooling and air cooling and dehumidiying coils Meal Thermal Resisance o Exernal Fins and Tube Wall or All Applicaions. The oal meal hermal resisance, R m, o hea low hrough he exernal ins and he prime ube wall is calculaed as ollows: R m = R + R (1) where he consan ube meal hermal resisance, R, is, R Bi 4k o ln i = Bi ln o k i and where he variable in meal hermal resisance, R, based on oal exernal surace eeciveness,, is R R 1 R a 1 R aw (or dry surace) () c p m" (or we surace) (a) 18

27 o AHRI STAAR s Ap A (3) A The inluence o m" on R aw, as shown in Equaion (a), is based on a derivaion by Brown (Reerence A1.7) which was applied o we coil heory by Ware-Hacha (Reerence A1.18) o deermine is implici eec on R. 6.. Sensible Hea Air Coils. Equaions relaing he average or raed sensible hea capaciy, q s, o boh air- and ube-side luid, by a maerial hea balance, are given in applicable paragraphs in ASI/ASHRAE Sandard 33. The idenical sensible hea capaciy, q s, corresponding o his maerial hea balance, in erms o he overall hea ranser rae beween luids is: q s Ao m (4) R where, or clean suraces, R = R a + R m + R w (or R v or R g or R r ) (5) R a R m Ra R (6) and, or cold and ho waer Laboraory Tes reducion (R a = 0) and raings (manuacurer may chose o use ouling acor allowances, see Reerence A.1. or ypical values): R w B 1 w R a (7) For seam: B Rv (7a) v For cold and ho aqueous ehylene glycol or aqueous propylene glycol soluion Laboraory Tes reducion (R a = 0) and raings (manuacurer may chose o use ouling acor allowances, see Reerence A1. or ypical values): R g B 1 g R a (7b) For volaile rerigeran: B Rr (7c) r 19

28 For all waer coils wih surace designs employing smooh inernal ube walls, he ube-side waer ilm hea ranser coeicien, w, where he Re exceeds 3100, is deermined using he curve i Equaion (8) shown in Figure 17. For waer coils using ube geomeries oher han smooh inernal walls, he ube-side waer ilm hea ranser coeicien, w, is deermined by es as in For seam coils, he ube-side seam ilm hea ranser coeicien, v, is evaluaed as described in Table, noe 3. For volaile rerigeran coils, he ube-side rerigeran ilm hea ranser coeicien, r, is evaluaed as described in For aqueous ehylene glycol or aqueous propylene glycol soluion coils, he ube-side aqueous ehylene glycol or aqueous propylene glycol soluion ilm hea ranser coeicien, g, is evaluaed as described in For waer coils: V w w ww w 4500Aix Aix (8) For aqueous ehylene glycol or aqueous propylene glycol soluion coils: V g wg 3600 A g ix wg g A ix (8a) For counerlow cold waer coils: 1db w db w1 m (9) 1db w ln db w1 For counerlow cold aqueous ehylene glycol or aqueous propylene glycol soluion coils: 1db g db g1 m (9a) 1db g ln db g1 For counerlow ho waer coils: m w 1db ln w w1 w1 1db db db (10) For counerlow ho aqueous ehylene glycol or aqueous propylene glycol soluion coils: m g 1db ln g g1 g1 1db db db (10a) 0

29 For hermal counerlow volaile rerigeran coils: m 1db r1 ln 1db db db r1 rcg rcg (11) For seam coils (single-ube): m ln db vmg vmg 1db 1db db (1) For seam coils (disribuing): m ln db vg vg 1db 1db db (1a) For oher ube circuiing arrangemens see Cooling and ehumidiying Air Coils. The mehod used in his sandard o calculae we surace coil perormance is, wih some modiicaions, similar o he mehod oulined in Technical Sandard BCMI-TS4044 (Reerence A1.6) wih basic heory as presened by McElgin and Wiley (Reerence A1.15). Oher invesigaors by convering he basic dual poenial, used in he mehod described in his sandard, o an equivalen single poenial, have developed oher similar raing mehods (Reerence A1.18 and Appendix B) Sensible Hea Raio. The raio o air-side sensible-o-oal hea is calculaed as ollows: q / q s 1 c p 1db db (13) h h The raio, q s /q, is used as an index o deine he ype o procedure required or calculaing raings as ollows: a. I q s /q < 0.95, use he equaions lised in he remainder o b. I q s /q 0.95, use he convenional dry surace, sensible hea ranser equaions lised under Toal Hea Capaciy or Toal Exernal Surace Area Requiremens. epending upon operaing condiions, he coil air-side surace may operae eiher compleely we or a porion o he coil may operae wih dry surace. For he case where all surace is compleely we, all surace emperaures, s, o he coil are below he enering air dew-poin emperaure, 1dp. For he case where he surace emperaures, s, o a par o he coil are above he enering air dew-poin emperaure, 1dp, his porion o he coil surace area, A, operaes dry wih he remainder o he coil surace area, A W, we or acively condensing moisure. For 1

30 his laer case, he coil surace area requiremens are separaely calculaed or he dry and we pars o he coil. For he we par o he coil, he we surace area, A W, or he corresponding oal hea capaciy, q W, is calculaed by using he mean air enhalpy dierence beween he air sream and ha corresponding o he coil surace emperaure. Equaions relaing he average or raed oal hea capaciy, q, o boh air- and ube-side luid, by a maerial hea balance, are given in applicable paragraphs o ASI/ASHRAE Sandard 33. The idenical oal hea capaciy, q, corresponding o his maerial hea balance, or he general case where a porion o he coil surace area operaes dry is: q A A h m W m (14) R c p RaW where: A R m q = ry surace capaciy A c W p h R m aw q W = We surace capaciy q q q = Toal hea capaciy required W The q erm in Equaion (14) is omied i he enire air-side surace is acively condensing moisure. For counerlow waer coils: Temperaure Enhalpy Coil eph Graphic represenaion o Equaions (15) and (16)

31 m 1db w ln 1db Bdb Bdb w wb wb (15) h h h h B sb s h m (16) hb hsb ln h hs For hermal counerlow volaile rerigeran coils: Temperaure Enhalpy Coil eph Graphic represenaion o Equaions (15a) and (16a) m 1db r1 ln 1db Bdb Bdb r1 rbg rbg (15a) h h h h B sb s h m (16a) hb hsb ln h hs For aqueous ehylene glycol or aqueous propylene glycol soluion coils: 3

32 Temperaure Enhalpy Coil eph Graphic represenaion o Equaions (15b) and (16b) m 1db g ln 1db Bdb Bdb g gb gb (15b) h h h h B sb s h m (16b) hb hsb ln h hs In he above equaions, h s reers o he enhalpy o sauraed air a he surace emperaure or he leaving air-side o he coil The Coil Characerisic. The coil characerisic is in erms o he individual hermal resisances: Rm Rw C (or waer) (17) c R p aw Rm Rr C (or volaile rerigeran) (17a) c R p aw Rm Rg C (or aqueous ehylene glycol or aqueous propylene glycol soluion) (17b) c R p aw And also, or any poin condiion wihin he we surace region, such as he erminal dierences, he coil characerisic is used o obain he correc division beween he air-side enhalpy dierence, h-h s, and ubeside emperaure dierence, s - w, s - rg, or s - g, as ollows: s w C (or waer) (18) h h s 4

33 s AHRI STAAR s rg C (or volaile rerigeran) (18a) h h s g C (or aqueous ehylene glycol or aqueous propylene glycol soluion) (18b) h h s C is calculaed rom Equaions (17), (17a) or (17b) using known values o R aw, R m and R w, R r or R g. Then wih known values o h and w, r or g a a given posiion wihin he we surace region, he corresponding values o s and h s may be exacly calculaed rom Equaions (18), (18a) or (18b) by rial and error using air enhalpy ables. A direc mehod or inding s and h s, o closely approximae he exac soluion given by Equaions (18), (18a) or (18b) may be obained by use o a universal Surace Temperaure Char, such as shown in Figure ry-we Boundary eerminaion or Parially ry Surace. Under operaing condiions where a porion o he coil is operaing dry, he boundary condiion beween he dry and we surace regions is esablished by calculaing he air sream enhalpy, h B, a his poin. For counerlow waer coils: h B 1dp w yh Ch 1 C y 1dp (19) For hermal counerlow volaile rerigeran coils: h B 1dp r1 yh Ch 1 C y 1dp (19a) For aqueous ehylene glycol or aqueous propylene glycol coils: h B 1dp g yh Ch 1 C y 1dp (19b) where: w w1 y (or waer coils) (0) h h 1 r1 rcg y (or volaile rerigeran coils) (0a) h h 1 g g1 y (or aqueous ehylene glycol or aqueous propylene glycol soluion coils) (0b) h h 1 5

34 I h B h 1, he enire coil surace area is we and A = 0. Only he we surace area, A W, is calculaed or his condiion. I h B < h 1, par o he surace is operaing dry. For his condiion, he dry, A, and we, A W, surace areas are separaely calculaed. The air dry-bulb emperaure a he dry-we boundary is: Bdb h1 hb 1 db (1) c p The oal hea load or he dry surace region is: q 60 w h h w h a 1 B a 1 h B 1000 () The oal hea load or he we surace region is: q W q q (3) The cold waer emperaure a he dry-we boundary wih counerlow coils is: q wb w (4) wwc pw The cold aqueous ehylene glycol or aqueous propylene glycol soluion emperaure wih counerlow coils is: q gb g (4a) wg c pg eerminaion o Leaving Air ry-bulb Temperaure. I 1dp, he coil surace is dry and he leaving air dry-bulb emperaure shall be calculaed using he mehod described in 6... For we or parially we coil surace, he leaving air dry-bulb emperaure, db, shall be calculaed as ollows: c Ao A A o o Ao 60c p wa Ra 14.58wa Ra 1000c p wa Ra 1017wa Ra (5) and also: c h hs db s e (6) h h 1 s 1db s 6

35 The sauraed air enhalpy, h, corresponding o he eecive coil surace emperaure,, is: h s h1 h h1 (7) c 1 e The leaving air dry-bulb emperaure, db, is hen calculaed as ollows: c e db s 1db s (8) eerminaion o Sensible and Laen Hea Capaciies. The air-side sensible, q s, and oal, q, hea capaciies are calculaed rom applicable equaions in ASI/ASHRAE Sandard Reducion o Laboraory Tes aa o eermine Parameers or Raings. The Forms reerenced herein are conained in AHRI OM-410 Addendum (Reerence A1.3) Coil Physical aa Calculaions. Procedure or calculaion o coil physical daa and in eiciency upon which boh analysis o Laboraory Tess and preparaion o raings are based, is deailed in AHRI OM-410 Addendum Form and is based on equaions lised under 4.1. Table 3. Meal Thermal Conduciviies Maerial Aluminum Alloy 1100 Temper O Aluminum Alloy 3003 Temper O Aluminum Alloy 3003 Temper H18 Copper (C11000) Copper (C100) Red Brass (85-15%, C3000) Cupronickel (90-10%, C70600) Cupronickel (70-30%, C71500) Admiraly (C44300, C44400, C44500) Seel-Carbon (SAE 100) Sainless Seel 304, 304L, 316, 316L Sainless Seel 410 and 40 Sainless Seel 347 and 31 See Reerences A1.9 and A1.11. Temperaure F [C] 77 [5] 77 [5] 77 [5] 68 [0] 68 [0] 68 [0] 68 [0] 68 [0] 68 [0] 1 [100] 1 [100] 1 [100] 1 [100] Thermal Conduciviy, k Bu/(h F) [10 3 Wmm/(m C)] 18.3 [1.7] [193.0] 89. [154.1] 6.0 [390.5] [338.7] 9.0 [159.0] 6.0 [44.9] 17.0 [9.4] 64.0 [110.6] 30.0 [51.8] 9.4 [16.] 14.4 [4.9] 9.3 [16.1] 6.3. Calculaion o Meal Thermal Resisance or Fin and Tube Assembly. Calculaion procedure or esablishing he meal hermal resisance, R m, is deailed in Form 410-1, and is based on equaions lised under o experimenal daa are required or hese calculaions. Meal hermal conduciviies or use in Form are conained in Table 3. 7

36 R m consiss o wo resisances in series: (a) he variable hermal resisance, R, o he exernal ins based on oal surace eeciveness or eiher dry or we surace, and (b) he consan hermal resisance, R, o he prime ube wall. epending upon ube design, R may or may no be negligible. An illusraive plo o (R a + R m ) vs. R a is shown in Figure 1 and is or dry surace applicaion only. This plo is used or analysis o eiher Laboraory Tes resuls or raings o sensible hea coils. An illusraive plo o R m vs. a or dry surace coils or R m vs. aw or we surace coils is shown in Figure. For we surace, he erm, m"/c p, is deermined rom Figure 8. The daa illusraed in Figure are used o deermine R m in eiher he analysis o Laboraory Tes resuls or or raings o all coil ypes. All calculaions o he in hermal resisance, R, shall be based on he in eiciencies,, as developed in Reerence A1.10. This daa by Gardner or annular shaped ins wih boh consan in hickness and consan in cross-secional area designs are shown, respecively, in Figure 10 and Figure 11. For non-circular shaped ins, he in segmenaion mehod, described in Reerences A1.8 and A1.16, may be used o compue he in hermal resisance, R. The in eiciency o he individual in segmens shall be based on daa by Gardner rom Figure 10 or Figure Air Sensible Hea Seam Coils. Calculaion procedure or deermining he perormance acors or seam coil raings derived rom Laboraory Tess, is deailed in Form This analysis is based on he applicable hea ranser equaions under 6... This procedure also includes parameers, based on experimenal resuls, used o deermine coil air-side pressure drop. The seam pressure drop inside ubes is deermined by he calculaion procedure as deailed in Form From analysis o Laboraory Tess on seam coils as oulined in Forms 410- and 410-3, he ollowing plos o experimenal daa are used or raings as illusraed in Figure 3: a. R vs. Va ps b. vs. Va r c. p L v e v vmg vs. w v c A ypical hermal diagram or seam coils wih luid emperaure designaions is shown on he las page o Form Air Sensible Hea Ho and Cold Waer Coils. Calculaion procedure or deermining he perormance acors or boh air sensible hea ho and cold waer coil raings derived rom Laboraory Tess, is deailed in Form This analysis is based on he applicable hea ranser equaions under 6... This procedure also includes parameers, based on experimenal resuls, used o deermine coil air-side pressure drop. The waer pressure drop inside ubes is deermined by he calculaion procedure as deailed in Form From analysis o Laboraory Tess on air sensible hea ho or cold waer coils as oulined in Form 410- and 410-3, he ollowing plos o experimenal daa are used or raings as illusraed in Figure 4 along wih waer perormance or smooh inernal ube coils rom Figure 17. 8

37 a. R a vs. Va R R vs. V b. a m a ps c. vs. Va r hl d. vs. Vw L F e For ube designs oher han smooh inernal ube walls, waer perormance rom shall be used. The acors, F and F h, shown in Figure 7, are used o correc he ube circui and header pressure drop, respecively, or oher average waer emperaures a consan mass low. Typical hermal counerlow diagrams or ho and cold waer coils wih luid emperaure designaions are shown on he las page o Form Cold Waer Cooling and ehumidiying Coils. Calculaion procedure or deermining he perormance acors or cold waer cooling and dehumidiying coil raings, derived rom Laboraory Tess, is deailed in Form This analysis is based on he applicable hea ranser equaions under Separae procedures are included or condiions where he coil surace is eiher compleely we or compleely dry. A parameer, based on es resuls, is included o deermine we surace coil air-side pressure drop. Besides we surace air-side pressure drop, he basic purpose o his series o ess is o deermine values o he we surace air ilm hermal resisance, R aw, over he raed range o coil sandard air ace velociy, V a, and o esablish wheher R aw diers rom he corresponding dry surace value, R a, a a given sandard air ace velociy. R aw and R a a a given value o V a may or may no be he same depending upon he paricular coil surace design and arrangemen. From analysis o Laboraory Tess on cold waer cooling and dehumidiying coils as oulined in Forms 410- and 410-3, he ollowing plos o experimenal daa are used or raings as illusraed in Figure 5 along wih waer perormance or smooh ube coils rom Figure 17: a. R aw vs. Va psw b. vs. Va r Also shown in Figure 5 are he ollowing daa rom Figure 4 (see 6.3.4) based on dry surace ess which are also applicable or parially we surace operaion: c. R a vs. Va ps d. vs. Va r 9

38 hl e. vs. Vw L F e For ube designs oher han smooh inernal ube walls, waer perormance rom shall be used. The acors, F and F h, shown in Figure 7, are used o correc he ube circui and header pressure drop, respecively, or oher average waer emperaures a consan mass low. A ypical hermal counerlow diagram or cold waer cooling and dehumidiying coils is shown on he las page o Form This diagram illusraes he condiion where a par o he coil surace is operaing dry. Air enhalpies, he emperaure condiions o luids and surace, and he dry-we boundary condiions are illusraed as used in he analysis given in Forms 410- and Volaile Rerigeran Cooling and ehumidiying Coils. Calculaion procedure or deermining he perormance acors or volaile rerigeran cooling and dehumidiying coil raings, derived rom Laboraory Tess, is deailed in Form This analysis is based on he applicable hea ranser equaions under Separae procedures are included or condiions where he coil surace is eiher compleely we or compleely dry. The basic purpose o his series o ess is o deermine he rerigeran evaporaing ilm hea ranser coeiciens, r, and he rerigeran pressure drops, p rc, hrough he coil ube circui. From analysis o Laboraory Tess on volaile rerigeran cooling and dehumidiying coils as oulined in Forms 410-4, he ollowing plos o experimenal daa are used or raings as illusraed in Figure 6. a. R r vs. q c b. p L v rc e rcg vs. w r c Also shown in Figure 6 are he ollowing daa rom Figure 5 deermined rom waer coil ess and previous calculaions. ps c. vs. Va r psw d. vs. Va r e. R a vs. Va. R aw vs. Va A ypical hermal counerlow diagram or volaile rerigeran cooling and dehumidiying coils is shown on he las page o Form This diagram illusraes he condiion where a par o he coil surace is operaing dry. Air 30