Describe accurately as possible the aim of this lab experiment and summarize the main finding

from your own lab experiment. How can this experiment be improved? Will classify the forced

convection as internal or external ?

Characteristics of the experiment:

Cross section of the Duct =0.015m2

Flat surface area =0.0225m2

Generator Power =200W

Overall fined Surface area =0.0480732m2

Emissivity of the finned surface =1

Emissivity of the flat surface =0.22

Typical data from the lab experiment are summarized in the following tables respectively for a

finned surface and for a flat surface.

Finned Surface

Flat Surface

Preliminary Question: Describe accurately as possible the aim of this lab experiment and summarize the main finding from your own lab experiment. How can this experiment be improved? Will classify the forced convection as internal or external ? Characteristics of the experiment: Cross section of the Duct = 0.015 m Flat surface area = 0.0225 m Generator Power = 200W Typical data from the lab experiment are summarized in the following tables respectively for a finned surface and for a flat surface. Finned Surface Working Percentage Surface Temperature in C Inlet Air Temperature in C (Tin) Outlet Air Temperature in C (Tom) Air Stream Velocity in m/s Electrical Power Supply in W Heat transfer coefficient in w/m k Heat Rate convected by air in W Nusselt Nu Reynolds Re Surface Efficiency Flat Surface Working Percentage Surface Temperature in C Inlet Air Temperature in C (Tin) Overall fined Surface area = 0.0480732 m Emissivity of the finned surface=1 Emissivity of the flat surface = 0.22 Outlet Air Temperature in C (To) Air Stream Velocity in m/s Electrical Power Supply in W Heat transfer coefficient in w/m k Heat Rate convected by air in W Nu Re Surface Efficiency 25 96 19.8 21.1 0.06 30 53 20 21.1 0.21 40 110 19.6 20.2 1.3 50 54 19.9 20.6 1.4 70 149 19.7 20.1 2.83 80 54 19.9 20.3 2.6 100 177 20 20.6 3.5 100 58 20 20.4 3.4