Pre-Lab - Experiment 3

It is suggested that you read the Lab Manual for Experiment 3 before you complete this Pre-Lab. Reading the lab manual will allow you to answer the following questions correctly and smoothly run through the Experiment procedures when you come in to class.

[1] Why does a combustion engine need fins? _____________________________________ ____________________________________________________________________________________________________________________________________________________________

[2] Observe Fourier’s heat equation: q” = kA(ΔT/Δx). What aspect of this equation allows for fins to increase heat transfer? Explain. ___________________________________________ __________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

[3] One assumption made in this experiment is that the base temperature (at x=0) is the same as the wall temperature of the main structure. Draw isotherms on the pictures below of the assumed and actual fin base conditions.

[4] The three fin sizes below will be examined in this experiment. Describe the tip condition for each of these sizes as described in the lab manual and in Table 3.4 of your Heat and Mass Transfer textbook.Short Fin: ______________________________________________________________________ ____________________________________________________________________________________________________________________________________________________________Medium Fin: ___________________________________________________________________ ____________________________________________________________________________________________________________________________________________________________Long Fin: ______________________________________________________________________ ____________________________________________________________________________________________________________________________________________________________

T∞=0h=constant

x

Tb=100 T∞=0h=variable

x

Tb=100