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DEVELOPMENT OF AN ADSOPTION COOLING SYSTEM WITH A

THERMAL ENERGY STORAGE BASED EVAPORATOR FOR AIR

CONDITIONING APPLICATIONFor

The FORD-HKUST Conservation and Environmental Research Program

Dept. of Mechanical & Aerospace Engineering

HKUST

© T.S. Zhao, 2014

Automobile fossil fuel emissions accounts for a huge 75% of total CO emission in the world.An estimated 70% pollution in the Asia pacific region is from the automotive sector.With over a billion vehicles running daily [UNEP,2013]

ENVIRONMENTAL BENIGN CARS USING EVRONMENTAL AND SUSTAINBLE COOLING SYSTEM LIKE THE ADASORPTION COOLING SYSTEMS CAN CUT DOWN THE POLUTION BUY 18% AS AIR CONDITIONERS AND COOLING SYSTEM ON VEHICLES ACOUNTS FOR ABOUT 9% THE TOTAL EMISSION ON THE CAR

OVERVIEW/PRESENTATION FLOW

© A. ONABANJI, 2015

INTRODUCTION

PRINCIPLE OF ACS

DESIGN METHODOLOGY

RESULTS

IMPLICATION OF RESULTS

STUDY RELEVANCE & APPLICATION

Adsorption Cooling System (ACS); An environmental benign cooling technology looking to replace conventional vapour compression cooling systems.

INTRODUCTIONProvide an Adsorption Cooling System “Off” Cooling Technology with the following attributes:

An incorporated latent thermal energy storage (LTES)

Passive system-No additional pump or moving parts required to existing system

Limited Modification to existing systems Simplified, lower cost approach than current

solutions Improved Refrigeration performance

z

Condenser

Evaporator

Adsorber

A

V3

V2

V4

V1

V6

V5

Adsorber

B

Adsorption Cooling Sys.

Phase 1

Adsorber A: DesorptionAdsorber B: Adsorption

Phase 2

Mass Recovery

Phase 3

Adsorber A: AdsorptionAdsorber B: Desorption

Simulation of a Double-bed Adsorption Cooling System

Sample of Composite Zeolite Adsorbent

Structure

Rate of Adsorption for some selected

Adsorbents

Adsorption PhenomenonAdsorbate; blue polar molecules, Adsorbent: hydrophilic surface.

XTERITICS OF THE ZEOLITE 13X/CaCl ADSORBENT

Adsorption and Desorption large temp

range

Microspores of diameter less

than 20 A (vacancy sites)

Low saturation pressures

(above atmospheric) at

operating temperature

Nominal Adsorbate

Uptake

Commercial features of Zeolite 13X/CaCl AdsorbentReliability

A stunning over200,000

cycles of adsorption/desor

ption

High Adsorption

• Adsorption at low humidity • Compact

structure

Adsorption

Temp. Range

• Solar Heat• Exhaust Heat

Working pair XteristicsADSORPTION&ADSORBENT

Zeolite 13X/CaCl Composite AdsorbentW

ADSORBENT PREPARATION & COATING

IMPREGNATION

• Zeolite(s) + CaCl(aq) • Ratio 1:9 • Filter and Rinse• Dry @ high temp.

>200oC

CALCINATION• Purification

by heating

COATING

• Spray Aqueous Composite adsorbent over the fins of heat exchanger


HEAT EXCHANGER BEFORE (A) AND AFTER (B) COATING

A

A B

Innovation; Incorporating a TES

System prototype testing

• Materials & Topography

• Replace weak and damaged pipes

• Poor ergonomics

• Poor Manufacturing

• Heat Loss study

• Cycle phase & mode Optimization

• Cycle time Optimization

• Poor Insulation

• Incomplete cycle mode

• Performance optimization

• Weight & Size

• Flow Circuits

• Harness• Leaks

Quantitative

Qualitative

Design/Approach

SCHEMATIC DESIGN MODEL


PCM HEAT EXCHANGER DESIGN

HEAT EXCHANGER LIVE PICTURE

Heat Exchanger

TubePCM drain

and tapTES

Chamber

3-D MODEL OF ADSORPTION COOLING SYSTEM PROTOTYPE


PREVIOUS DESIGN CURRENT DESIGN

EVAPORATOR

CONDENSERVACUM VALVES

ADSORBER BEDS

Flow meter

Temperature Sensor

Insulated Hot Water Tank

Actuator VavlesPICTURE OF

THEADSORPTION

COOLING SYSTEM

Pen-tadecane offers a narrow temperature fluctuation during charge and discharge for the systems operating temp. Very low volume change during phase change. Overall surface contact area with heat exchanger. High storage density at operating temp as compared to sensible heat.


PCM SELECTION CRITERIASustainability

&Stability

Recyclable

Chemically Inert

and StabilitySelf

Nucleating And

Reversibility

Thermal Properties

AppropriateThermal

ConductivitySteady-latent

heat of Absorption

and emission

No PhaseSegregation

Operating Temperature

RangeNarrow

temperature fluctuation

Thermal stabilty

Narrowtemperature fluctuation

EXPERIMENTAL ACS-TES SYTEM CYCLE


V-V2

SV3

Cond.

SV1

SV6

SV2

SV5

SV4

ADS-B

Evap.

ADS-ASV8

SV7 V-V3

V-V1V-V4

V-V5

PCM Chamber

Chilled

water flow

Cooling

water flow

Red Flow= Hot WaterBlue Flow= Cold WaterYellow Flow=Refrigerant Black Flow=Adsorbate

V-V= Vacuum ValvesSV=Adsorbate valve

DESORPTION

Cold

Cold

Cold

Cold

ADSORPTION

Hot

Hot

Hot

Hot


CONTINOUS TEMP FLUCTUATION (MIN.

TEMP. = 8OC)

PLOT OF TEMPERATURE PROFILES OBTAINED FOR NO LOAD ON THE ACS

HEAT TRANSFER FLUID TEMPERATURE PROFILE OF THE ADSORPTION COOLING SYSTEM FOR A 0.3 KW LOAD


CONTINOUS TEMP.

FLUCTUATION


PCM OUTLET TEMP.

REDUCED FLUTUATION

CHILLED WATER OUTLER TEMP.

TEMPERATURE PROFILES FOR ACS-TES SYSTEM

Authors Adsorbent-Adsorbate pair

SORPTION TEMPRATURE

APPLICATION COP SCP(W/kg)

Zhang L. Z. et al. [1] , (2000)

Zeolite 13X – water

310 Air conditioning 0.38 25.7

Wang R. Z. et al. , (2001)

Activated carbon – methanol

100 Chilled Water 0.4 73.1

Lu Y. L. et al. (2004)

Zeolite 13 X –Water

300 Air conditioning 0.21 30

Restuccia G. et al.(2004)

Silica gel – water 80 Chilled water 0.58 20

Liu Y. L. et al. 2005

Silica gel – water 85 0.188 43

Yu.I.Aristov et al. ,(2010)

LiNO3/silica KSK - Water

80 Chilled water 0.086 144

Chao Y. H. et al. (2012)

Zeolite 13X/CaCl-water

70 Chilled water O.1 1O6

Present System (2015)

Zeolite 13X/CaCl-water

80 Chilled water/Trucks

0.08 160

COMPARISON OF RESULT


PROPERTIES Previous Model Optimized Model RemarksSpecific Cooling Power 655(W/kg) 160(W/kg) 75% less as compare to

previous system

Size/Weight 0.86 sq.meters area&

Aprox.130kg

0.80 sq. meters area

&Aprox. 109kg

Weight Optimization;1 9% weight

reductionCo-eifficent of Performance(COP) 0.45 0.08 400W cooling capacity, a

poor 82% less than previous model

Cycle Time 60 (mins) equivalent to 8cycles

60 (mins) equivalent to

5cycles

Cycle mode optimization

Heat exchanger efficiency Non-coated heat exchangers thus Redox reactions

in chamber

Heat exchangers are selected for

thermal and corrosion

resistance for refrigerant type

Improved efficiency in new

model as compared to the previous model

Chilled Water Temperature High fluctuation of Chilled water Temperature

Quasi-stable Chilled water fluctuation

Improved through the TES incorporation.

RESULT SUMMARY & IMPLCATION


Integrating chilled Air

outlet to the system for ambient

temperature cooling

Regenerative cycle for

condenser cooling source

to reduce cooling water temperature

Size and Weight

reduction of the

system

Integrating the system

on a Vehicle


Using a Solar hot water system for hot water source for the system

&Integrating PCM with

Nano-particles for improved thermal

conductivity

RECOMMENDATION

APPLICATION

Stadiums


Solar Impulse II & Solar Powered Trucks

Rural & Suburban Societies

Marine Vessels

REFERENCES• Tso, C. Y., Christopher YH Chao, and S. C. Fu. "Performance analysis

of a waste heat driven activated carbon based composite adsorbent–water adsorption chiller using simulation model." International journal of heat and mass transfer 55.25 (2012): 7596-7610.• C.Y. Tso, K.C. Chan, Christopher Y.H. Chao, C.L. Wu. Experimental

performance analysis on an adsorption cooling system using zeolite 13X/CaCl2 adsorbent with various operation sequences. International Journal of Heat and Mass Transfer 85 (2015) 343–355• R.Z. wang, R.G. Oliveira, adsorption refrigeration-an efficient way

to make good use of waste heat and solar energy, progress in energy and combustion science 32(2006) pp 424-458.

QUESTIONS???

•Prof. CHRISTOPHER CHAO•Mr K C Chan (Oscar)•Mr Edwin Tso •FORD-HKUST Conservation and Research Program.

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