POLYMERIC MATERIALS USED AS HEAT EXCHANGERS

•PVDF

•NYLON 6

•PTFE

•PEEK

Potential Advantages of Polymer Heat Exchangers

•Resistance to Corrosion

•Resistance to Fouling

•Light Weight

•Cost Benefits

Potential Applications of Polymer Heat Exchangers•Heating and Cooling in Electroplating and Anodizing Processes

(Currently tubular PTFE exchangers are used)

•Heating and Cooling Applications in Sulphuric Acid Plants

•Bromine Recovery systems

•Acid Dilution systems for the battery industry

•Secondary heat exchanger in Condensing gas boilers

•Flue gas heat recovery systems

•Aviation and Automobile Industry

•Air conditioning systems

•Convective Heat Transfer & Pressure Drop Characteristics (Air / Air , Water / Water, Air / Water)

•Effect of Angle of Cross Corrugation

•Effect of Pr Number

•Condensation in the presence of non- condensibles

•Mass transfer studies

•Flow visualisation studies

Continued

Cross Corrugated Film

Exchanger Matrix

Details of the Heat Exchanger

Projected Heat Transfer

Area

0.624 m2

Actual Heat Transfer

Area

1.21 m2

Hydraulic Diameter Dh 1.2 x 10-3 m

L/Dh 1.5

Heat Transferred per unit Exchanger Volume (Water/Water)

TYPE Z (MW/EFFECTIVE

MATRIX VOL (m3) (For

temp. difference of 5 0C)

Reynolds No.

PFCHE 24.0 1000

PF 7.83 3000

Shell - tube 0.35 50000

Heat Transferred per unit Exchanger Volume

TYPE Z (MW/Effective Matrix

Vol. (m3) (For temperature

difference of 5 0C)

Reynolds No.

PFCHE 1.09 800

Serrated Fin 0.6 800

Wavy Fin 0.27 800

Flat Tubes 0.16 800

Jh and F correlations for various configurations and Pr values

Prandtl

Number

Cross

Corrugation

Angle

Jh f

0.7 300 Jh = 0.4127 Re - 0.55 f = 0.6005 Re -0.142

0.7 600 Jh = 0.029 Re - 0.173 f = 0.693 Re -0.154

0.7 900 Jh = 0.0143 Re - 0.124 f = 0.057 Re-0.146

7.0 900 Jh = 0.2208 Re -0.6979 f = 1.4709 Re -0.7912

19 900 Jh = 0.0885 Re -0.6259 f = 1.6544 Re -0.7084

Jh 30 0 / Jh 90 0 = 1.85

Jh 60 0 / Jh 90 0 = 1.48

What about Thermal Resistance?

Liquid 5000 W/m2 K Resistance 0.0002m2 K/W

Gas 400 W/m2k Resistance 0.0025 m2 K/W

Film t=53. 10 -6 m, k = 0.2 W/m K Resistance 0.000265 m2 K/W

Film / Liquid 1.32

Film / Gas 0.106 (If t=0.9mm) Film/Gas =1.8

Film / Liquid (2500 W/ m2 K) 0.66