# Heat and mass transfer of polymer in twin screw extrusion

Essay by xflazexUniversity, Bachelor'sA, November 2014

1 | P a g e

1.0 CONTENT

Content Page

1.0 Content 1

2.0 Literature Review

2.1 Extruder 2-4

2.2 Polystyrene (PS) 5-6

3.0 Methodology

3.1 Material 7

3.2 Equipment 7

3.3 Procedure 8

3.4 Testing and characterizations 9-10

4.0 Result and discussion

4.1 Effect of screw design on temperature at each temperature zones 11-12

4.2 Effect of screw speed on flow rate in extrusion 13-15

4.3 Effect of temperature on heat transfer in extrusion 16-18

5.0 Conclusion 19

6.0 References 20

7.0 Appendix 21-26

2 | P a g e

2.0 INTRODUCTION

This experiment was constructed to study the relationship between processing parameter and heat

and mass transfer in twin screw extruder. Productivity, homogeneity and quality of product can be

alternating by using heat and mass transfer concept.

There are 3 types of heat transfer which are convection, conduction and radiation heat transfer [1].

Convection heat transfer happen when thermal energy density differences which is caused by particles

themselves due to heating. However, forced convection do not occur in this experiment since cooling

down with water bath is a free convection heat transfer. Radiation heat transfer occur only when emit or

absorb radiative energy by lowering or raising their molecular energy levels. However, radiation heat

transfer do not involved in this experiment. Lastly, conduction radiation heat transfer happen between

wall surfaces to molecular particle.

Fourier's law is the main equation used in calculation of heat transfer. This law involved the idea

that the heat flux is proportional to the temperature gradient in any direction ð, where ð´ is area of system,

ð is thermal conductivity of material and ð is temperature involved.

ð»ððð¡ ððð¢ð¥, ðð¥ = âðð´ ðð

ðð

By deriving Fourier's law, other equations can be obtained and used in this experiment and it will

show in...