Current Work on PCM Fins

8/16/2019 Current Work on PCM Fins

1/7

1. Analysis of geometrical and operational parameters of PCM in a fin and

tube heat exchanger (2014(!eat and mass "ransfer

#ote$ %xperimental &or'.

1. Fin and tube heat exchanger 2. solidification and melting

3. PCM = R35

4. HF= !ater

5. "n#estigate the effect of flo$ rate% inlet tem&erature and geometrical &arameter 'fin &itch(

on charging and discharging &rocesses of the &hase change material.

). he shell side is a rectangular and a continuous spiral tube that carries the

$ater inside the shell.

2. Analysis of !"s) PCMs and fins effects on the thermal performance

of shell*tube thermal energy storage units (201+ (,olar %nergy

#ote$ #umerical -or' (/

*. PCMs = including &ure +a+,3 and a com&osite

of +a+,3-ex&anded gra&hite '/(

2. HF= s0nthetic oil and molten salts.

3. charging-discharging &rocess%

4. ffects of the extended fin%

5. his stud0 is ex&ected to &ro#ide an a&&rehensi#e inter&retation of thermal trans&ort

mechanism and rational ad#ices in o&timi1ing the s0stem o&eration.

. An effectieness#" techni3ue for characterising a finned tubes PCM

system using a C/ model (Applied %nergy(201+

#ote$ #umerical -or' (2/

*. $o dimensional mathematical model% based on the effecti#enessnumber of transfer units

techniue.

2. Radial Fins.

3. he model a&&lies an em&iricall0 deri#ed P factor $hich defines the &ro&ortion of the heat

flo$ $hich is &arallel and isothermal.

4.P factor $as determined using a #alidated com&utational fluid d0namics model. his

method is used to design and o&timise tubeintan salt based &hase change thermal storage

units $ith finned tubes.

5. PCM = !ater and salt h0drate.

4. A numerical method for PCMbased pin fin heat sin's optimiation (energy

conersion and management(201+


2/7

#ote$ #umerical -or' (/

*. /eometric o&timi1ation of PCMbased &in fin heat sins.

2. Paraffin R44HC is used as PCM

3. Fins are made of aluminium.

4. aguchi method $ith numerical simulations is utili1ed for this &ur&ose. +umber of fins%

fins height% fins thicness and the base thicness are &arameters $hich are studied for

o&timi1ation.

5. Results sho$ that a com&lex relation exists bet$een PCM and C #olume &ercentages.

he o&timal case strongl0 de&ends on the fins6 number% fins height and thicness and also the

critical tem&erature.

+. Closecontact melting in a horiontal cylindrical enclosure &ith longitudinal plate

fins$ /emonstration) modeling and application to thermal storage.(!eat and mass

transfer(201+

#ote$

1. closecontact melting 'CCM( ($hich ma0 significantl0 increase the melting rate% has not

been ex&lored(.

2. "n the &resent ex&eriments% a laborator0scale threefin unit is trans&arent and thus the

&rocesses inside it are obser#ed and recorded. Closecontact melting is achie#ed b0 su&&l0ing

heat to the outer shell of the unit7 the solid &hase is detached from the shell and mo#es in the

liuid &hase.

3.8 no#el theoretical model includes gra#it0induced rotational motion of the solid% &rimar0

melting on a #ertical fin $ith nonuniform tem&erature distribution% secondar0 melting at the

shell% and frictional resistance at the latter.

4. he model is #alidated using the ex&erimental results% and then used for a

&arametric in#estigation and dimensional anal0sis.

5. "t is re#ealed that the melt fraction de&ends on the Fourier and tefan numbers combined.


3/7

5. Constructal design of horiontal fins to improe the performance of phase change

material rectangular enclosures (Applied thermal %ngineering(201+

#ote$

*. he &ur&ose of the current stud0 is to determine the effect of adding hori1ontal fins to

im&ro#e the efficienc0 of a heat sin. he reuired time for the maximum tem&erature of the

heat sin to reach its critical #alue is maximi1ed in#oing constructal theor0.

2. 9egrees of freedom are the number of enclosures% hori1ontal fins number and heat sin

as&ect ratio% $hile the entire surface area and the PCM content are constraints.

3. he results indicate that the best maximum safe o&eration time occurs in an o&timum #alue

for the hori1ontal fins number.

4. he results sho$ that for lo$ number of enclosures% heat sins $ith high as&ect ratios are

su&erior: $hile% for high number of enclosures% heat sins $ith lo$ as&ect ratios ha#e better

&erformance.

5. 8dding geometrical com&lexities to the heat sin $ill not necessaril0 im&ro#e the

&erformance of the enclosure.

6. 7P accelerated numerical study of PCM melting process in an enclosure &ith

internal fins using lattice 8oltmann method

*.he gra&hics &rocessing units '/P;( com&uting

2.he melting &rocess in PCMs $as in#estigated for different materials of

fins and $alls% number of fins% fin configurations% hot $all tem&erature% thermal boundar0

conditions% and inclination angle of the PCM ca#it0.

3.


4/7


5/7

10. Maximiation of performance of a PCM latent heat storage system

&ith innoatie fins (Applied %nergy(201+

#ote$ #umerical

*. "n this &a&er the use of tree sha&ed fins is &ro&osed to enhance the &erformance of a shell

andtube


6/7

)."nserting fins leads to the significant enhancement of the melting and solidification rate.

A."t is more efficient during the solidification &rocess due to the su&&ression of the natural

con#ection effect during the melting &rocess.

12. #umerical inestigation of PCM melting process in sleee tube &ith internal fins

(%nergy conseration and management(2015

#ote $ #umerical

*. o anal01e the im&act of fin geometr0 'including finlength% finratio and the angle bet$een neighbor fins( and outer tube conducti#it0 on PCM melting &rocess:

2. he influence of the natural con#ection in the hori1ontal slee#etube unit $ithin the

longitudinal fins is further examined.

3. Results sho$s that small finratio can reduce melting time% but not remarabl0: the angle

bet$een neighbor fins has little im&act on melting &rocess%

4. ,&timi1ation of the angle bet$een neighbor fins to reduce melting time in the fullscale

unit.

5.he outer tube conducti#it0 has great im&act on melting &rocess $hether considering the

natural con#ection or not.

1."hermal performance enhancement of shell and tube


7/7

'HF(.

3.x&erimental results sho$ that the heat transfer augmentation is more sensiti#e to increase

in

HF inlet tem&erature as com&ared to increase in mass flo$ rate of HF. olidification time

has been obser#ed to reduce u& to 43.) b0 installation of three fins.

Current Work on PCM Fins

Documents

Transcript of Current Work on PCM Fins