presentation exergy analysis in radiant heating system

8/8/2019 Presentation Exergy Analysis in Radiant Heating System

1/16

Double Master Degree on Energy and EnvironmentDouble Master Degree on Energy and Environment

Presented by :Presented by :

Muhammad Penta HeliosMuhammad Penta Helios(20092807003)(20092807003)


2/16

RadiantRadiant heatingheating systemsystem usuallyusually usesuses inin

manymany europeeurope countriescountries toto heatingheating roomroom

spacespace inin winterwinter seasonseason.. ThisThis systemsystem hadhad beenbeen

developeddeveloped sincesince 19901990ss whichwhich itit consideredconsideredenergyenergy conservationconservation andand heatheat transfertransfer inin

buildingbuilding withwith anan exteriorexterior wallwall.. MainMain purposespurposes

ofof thisthis studystudy areare toto gaingain insightinsight howhow muchmuch

buildingbuilding conctructionsconctructions consumeconsume energyenergy andandcalculatecalculate energyenergy efficiencyefficiency byby usingusing exergyexergy

methodmethod.. Commonly,Commonly, radiantradiant heatingheating systemsystem

setssets upup betweenbetween roofroof andand ceilingceiling ofof househouse..


3/16

BasedBased onon thethe jounal,jounal, whenwhen radiantradiant

heatingheating systemsystem isis workingworking.. TheThe insulationinsulation

suchsuch as,as, wallwall andand windowwindow cancan notnot preventprevent

thethe heatheat flowingflowing outout toto thethe outside,outside, soso ititmakesmakes unefficiencyunefficiency energyenergy..

InIn thisthis study,study, writterwritter willwill makemake

comparisoncomparison betweenbetween roomroom withwith aa windowwindow

andand roomroom withoutwithout aa windowwindow..NoteNote :: thisthis studystudy locatedlocated inin NetherlandsNetherlands

wherewhere thethe roomroom windowwindow lookedlooked

towardstowards thethe sunsun..


4/16

InIn figurefigure 11,, wewe cancan looklook howhow radiantradiant

heatingheating systemsystem workwork..

Figure 1. Radiant heating systemFigure 1. Radiant heating system

Solarradiation

Power plant

Fuel(gas)

Heatpump

Ceiling radiant panel

Room space


5/16

initially,initially, heatheat energyenergy cancan bebe obtainedobtained byby

fuelfuel combustioncombustion inin powerpower plantplant oror collectingcollectingsolarsolar energyenergy fromfrom thethe sunsun.. Furthermore,Furthermore, thethe

heatheat fromfrom thethe sunsun willwill hothot upup exteriorexterior wallwall

directlydirectly whereaswhereas heatheat energyenergy fromfrom powerpower plantplant

combustioncombustion willwill bebe convertedconverted toto electricityelectricity..Then,Then, duringduring thethe solarsolar energyenergy heatheat isis

transferredtransferred fromfrom thethe wallwall andand floorfloor surfacessurfaces toto

thethe roomroom air,air, electricityelectricity willwill operateoperate heatheat

pumppump toto produceproduce warmwarm waterwater.. Finally,Finally, warmwarmwaterwater willwill bebe circulatecirculate insideinside radiantradiant heatingheating

systemsystem toto reducereduce coldcold temperaturetemperature inin roomroom airair..

TheThe heatheat transferedtransfered processprocess waswas occuredoccured byby

emittingemitting longlong wavewave radiationradiation..


6/16

Figure 2. Sketch room with a windowFigure 2. Sketch room with a window

and without windowand without window


7/16

InIn firstfirst of,of, basedbased onon exergyexergy conceptconcept(Shukuya,(Shukuya, 20022002)).. WeWe willwill analyzeanalyze sequencesequence ofof

thethe systemsystem processprocess wherewhere eacheach partpart ofof thethe

systemsystem requiresrequires differentdifferent energyenergy needneed.. ToTo

facilitatefacilitate exergyexergy analysis,analysis, thethe amountamount ofofrequiredrequired energyenergy isis divideddivided intointo 22 twotwo sideside

zones,zones, namelynamely ::

11.. SupplySupply sideside (sun(sun andand fuel)fuel)

zonezone wherewhere heatheat isis transferedtransfered fromfrom sunsunandand powerpower plantplant

22.. DemandDemand sideside

zonezone wherewhere heatheat energyenergy fromfrom supplysupply sideside

isis requiredrequired


8/16

BesidesBesides thethe amountamount ofof requiredrequired energyenergy..

AbvailableAbvailable workwork inin systemsystem cancan bebe calculatedcalculated

byby simplifyingsimplifying allall partsparts ofof systemsystem intointo sixsix

subsystems,subsystems, namelynamely ::

11.. PowerPower plantplant

22.. HeatHeat pumppump33.. CeilingCeiling radiantradiant panelpanel

44.. InteriorInterior wallwall surfacesurface

55.. FloorFloor surfacesurface

66.. RoomRoomwhere all of subsystems will be

examined by energy, entropy, and exergybalance equations.


9/16

InIn thisthis journaljournal thethe exergyexergy calculationcalculation waswas

calculatedcalculated byby usingusing energy,energy, entropy,entropy, andand

exergyexergy balancebalance equationsequations.. WithWith modifyingmodifying

thethe basicbasic equationequation writterwritter waswas obtainedobtained allallofof thethe equationsequations.. ItIt isis shownshown inin EqEq.. 11,, EqEq.. 22

andand EqEq.. 33

EnergyEnergy balancebalance equationequation

..........EqEq.. 11

EntropyEntropy balancebalance equationequation

......EqEq.. 22

nqdtdTVCnq out

m

k

wkkkpkin !

!1

V

nTnq

nTdt

dTVCns

nT

nq

wk

outm

k wk

wkkkpkg

wk

in

! !1

1.V


10/16

Exergy balance equationExergy balance equation

Eq. 3Eq. 3

AllAll ofof thethe equationsequations aboveabove areare usedused toto

comparingcomparing finalfinal totaltotal amountamount ofof exergyexergy inin

twotwo radiantradiant heatingheating systemssystems (with(with aa windowwindowandand withoutwithout aa window),window), wherewhere thethe UU--valuevalue

hashas beenbeen discerneddiscerned thethe finalfinal resultresult.. InIn thethe

otherother words,words, nono heatheat cancan breakbreak throughtthrought inin

toto thethe roomroom..BecauseBecause ofof seasonseason influencedinfluenced oror periodperiod

timetime (the(the summersummer seasonseason occuredoccured fromfrom

OctoberOctober toto April),April), exergyexergy equationequation shownshown

equationequation 44 cancan bebe modifiedmodified

!

! nT

nTnqnT

nT

dt

dTVCnTnsnT

nTnq

wk

out

m

k wk

wkkkpkg

wk

in00

0

0

. V


11/16

AfterAfter wewe getget amountamount ofof exergyexergy fromfrom

eacheach partpart.. WeWe cancan sumsum itsits toto getget totaltotalamountamount ofof exergyexergy inin thethe systemsystem..

NoteNote :: thethe energy,energy, entropy,entropy, andand exergyexergy balancebalance

equationsequations forfor ceilingceiling radiantradiant panelpanel werewereshownshown byby referencesreferences (asada(asada andand Takeda,Takeda,

20022002,,20032003)) andand forfor subsystemssubsystems cancan bebe

derivedderived fromfrom referencesreferences jounaljounal AsadaAsada

andand Shakuya,Shakuya, 19941994,,19961996,,19991999))..

(

!

!!! nT

nTnqt

nT

nTnTnTnTVC

wk

out

f

in

m

k wk

kwkwkkpk

f

in

0

1

0

01.1ln1V

nTnstnT

nTnqt g

f

inwk

in

f

in

0

0..1.

!!

(

-

(


12/16

FigureFigure 3. Exergy result for room3. Exergy result for room

with a windowwith a window


13/16

Fi r . r r s lt f r r it tFi r . r r s lt f r r it t

ii


14/16

fromfrom thisthis researchresearch inin thethe journal,journal, thethe

comparisoncomparison betweenbetween roomroom withwith aa windowwindow andandwithoutwithout aa windowwindow areare shownshown inin figfig.. 22 andand figfig.. 33,,

wherewhere thethe blackblack barbar showsshows thethe exergyexergy

comsumptioncomsumption forfor eacheach subsystemssubsystems andand whitewhite

barbar belowbelow showsshows thethe exergyexergy whichwhich isis consumedconsumedbyby absorptionabsorption andand conversionconversion toto heatheat exteriorexterior

wallwall surface,surface, interiorinterior wallwall surface,surface, andand floorfloor byby

usingusing fuelfuel combustioncombustion andand solarsolar heatingheating..

Eventhough,Eventhough, thethe amountamount ofof energyenergy suppliedsupplied

inin thisthis twotwo casecase isis similarsimilar.. TheThe exergyexergy needneed inin

roomroom withwith aa windowwindow isis biggerbigger thanthan roomroom

withoutwithout aa windowwindow.. BecauseBecause ofof UU--valuevalue andand

thermalthermal absorptionabsorption inin exteriorexterior wallwall..


15/16

ExergyExergy consumptionconsumption inin thethe roomroom isis

relativelyrelatively smallsmall (compared(compared toto thethe supplysupply

side)side).. ForFor thethe roomroom withoutwithout aa window,window, moremore

exergyexergy isis consumedconsumed thanthan suppliedsupplied atat thetheexteriorexterior wall,wall, reflectingreflecting thethe heatheat storagestorage

effecteffect inin thethe buildingbuilding massmass..


16/16

presentation exergy analysis in radiant heating system

Documents