Prediction of batch heat transfer coefficients for pseudoplastic fluids ...
Prediction of batch heat transfer coefficients for pseudoplastic fluids ... Prediction of batch heat transfer coefficients for pseudoplastic fluids ...
8 curve (Curve B) is straigkt at the tw0 extremes ei' sl!lJ.ear main~er. Tke sl~pes o~ the str&ight p&rtions are tae Newten.iaE. ViS60sities f'0r that regiea, ancil. tile slope of' !it bet1'J'een any Fl0int or the curved ~@rtion lime and zer® gives the apparent viscosity at that shear rate. Tke Newtonian viscosity at l0i-J shear rate is orten called the tl zero shear-rate vis- . t It 1/ cos:t. y '/~o. Likewise, the Newtonian viscosity at very hi~ shear rates is of'te:m named the "i:V1i'inite shear-rate viscositytl, /Leo. The l®gari t~ic rlOl-J curve (Curve C) e01l.ltai1l.ls three straight lines. The two extreme lines R&Ve a slope or unity and rSFlresent the Newtonian p0rtions @f the shear rate spectrum. The middle line h.a.s a slope "'\AThich is beti.reen zer@ aRd uni ty. The closer to zero it is, the more non-Newtonian tae f'luid. T.hl.e shear-rate range or the Ilzero shear-rate viacosi tylf is of'ten very narr0W. The Iti:afinite shear-rate viscositylt occurs at very high Shear rates and is very seldom encountered in industrial proeesses sueh as f'low through a conduit, heat transfer, or mLxing 1~th or turbine .. a paddle, anchor, marine propeller, 'A f'eirJ special impellers and precesses (such as bl7US1'1l.ing of' a paint) produce hi~ :hear rates, so that the infini te shear-rate visc0sL ty may be approached. Many authors 'have tried to derive theoretical expressions i'or the fl®w eurv~s ef pseua@~lasties ana mamy ethers have tried t@ aevelep empirical equati@ms (79, 109, 135, 152, 154
15.5, 183, 185).. Most of their efforts 'i-Jere in vain because the equations vJere not very accurate or '>Jere too complex to 1.Jork I'Jith (120). Huch of the early teclmological lvork vJas done using an empirical equation to express the flow curves (22, 214, 215). (2-1 This relationship, the Williamson equation, is fairly complicated, and is valid for only a small nu.mber of fluids" In an effort to simplify the equation, the first term lims often dropped, placing too much emphasis on the infinite shear-rate viscosity, "lv-hich in practice is rarely approached (22, 118). Another equation for describing pseudoplastic flow behavior which has gained some acceptance is the Pm'
- Page 1 and 2: Copyright Warning & Restrictions Th
- Page 3 and 4: PREDICTION OF BATCH HEAT TRANSFER C
- Page 5 and 6: while the latter has five to seven
- Page 7 and 8: ACKNOWLEDGEMENTS The auther ex~ress
- Page 9 and 10: Chapter 1: Chapter 2: Introducticm
- Page 11 and 12: LIST OF FIGURES page 2-1 FlGW Behav
- Page 13 and 14: CHAPTER I INTRODUCTION BATCH HEAT T
- Page 15 and 16: 3 as pseudoplasticso Pseudoplastic
- Page 17 and 18: 5 ~n addition to studying the effec
- Page 19: 7 A B SLOPE = /'n- .( 10 ~y FIG 2-1
- Page 23 and 24: va:ry withl. the slaear I'Rte.. 11.
- Page 25 and 26: 13 RHEOLOGIC_~ INVESTIGATION OFPO~~
- Page 27 and 28: IS In(s) (2-8 (2-9 where Re is the
- Page 29 and 30: '7 ft~ easier method of calibrating
- Page 31 and 32: 19 of' thixotropic breakdown l'Ji t
- Page 33 and 34: 21 complicated by a variable viscos
- Page 35 and 36: 2J Schultz-GrQnow (174) used a dime
- Page 37 and 38: 2S The results shm-red that equatio
- Page 39 and 40: Su.bstituti011 of equati 2-22 gives
- Page 41 and 42: 29 In both Newtonian and non-Newton
- Page 43 and 44: 31 for viscous pseudoplas tics at 1
- Page 45 and 46: 33 (2-29 when both the distances ar
- Page 47 and 48: JS Thermometers or thermocouples ar
- Page 49 and 50: .37 2: a in in heat cQ@tent of the
- Page 51 and 52: J9 cooling mediu..:m side, the heat
- Page 53 and 54: 41 ports a value of 3/4-.. He then
- Page 55 and 56: 43 find the effects of one or two o
- Page 57 and 58: 45 The group to the left of the equ
- Page 59 and 60: 47 the highest heat tra...nsfer coe
- Page 61 and 62: 49 A pitched blade turbine gave coe
- Page 63 and 64: SI done on the correlation of heat
- Page 65 and 66: 5J evaluated at the wall temperatur
- Page 67 and 68: ss to (2-46 where ill is the consis
- Page 69 and 70: CHAPTER .2 DEVELOPMENT OF CORRELATI
8<br />
curve (Curve B) is straigkt at the tw0 extremes ei' sl!lJ.ear<br />
main~er. Tke sl~pes o~ the str&ight p&rtions are tae Newten.iaE.<br />
ViS60sities f'0r that regiea, ancil. tile slope <strong>of</strong>' !it<br />
bet1'J'een any Fl0int or the curved ~@rtion<br />
lime<br />
and zer® gives the<br />
apparent viscosity at that shear rate. Tke Newtonian viscosity<br />
at l0i-J shear rate is orten called the tl zero shear-rate vis-<br />
. t It 1/<br />
cos:t. y '/~o.<br />
Likewise, the Newtonian viscosity at very hi~<br />
shear rates is <strong>of</strong>'te:m named the "i:V1i'inite shear-rate viscositytl,<br />
/Leo. The l®gari t~ic rlOl-J curve (Curve C) e01l.ltai1l.ls three<br />
straight lines. The two extreme lines R&Ve a slope or unity<br />
and rSFlresent the Newtonian p0rtions @f the shear rate spectrum.<br />
The middle line h.a.s a slope "'\AThich is beti.reen zer@ aRd uni ty.<br />
The closer to zero it is, the more non-Newtonian tae f'luid.<br />
T.hl.e<br />
shear-rate range or the Ilzero shear-rate viacosi tylf<br />
is <strong>of</strong>'ten very narr0W.<br />
The Iti:afinite shear-rate viscositylt<br />
occurs at very high Shear rates and is very seldom encountered<br />
in industrial proeesses sueh as f'low through a conduit, <strong>heat</strong><br />
<strong>transfer</strong>, or mLxing 1~th<br />
or turbine ..<br />
a paddle, anchor, marine propeller,<br />
'A f'eirJ special impellers and precesses (such as<br />
bl7US1'1l.ing <strong>of</strong>' a paint) produce hi~ :hear rates, so that the<br />
infini te shear-rate visc0sL ty may be approached.<br />
Many authors 'have tried to derive theoretical expressions<br />
i'or the fl®w eurv~s ef pseua@~lasties ana mamy ethers have<br />
tried t@ aevelep empirical equati@ms (79, 109, 135, 152, 154
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