1. Todd Nelson Kendall Thacker ME 340 Semester Project Winter 2014

2.  How long will it take for the outside surface of an ice cream cone to arrive at melting temperature* while walking around?  *Melting occurs at -5.6°C

3. 1) Find properties of air and ice cream at appropriate temperatures 2) Calculate forced convection coefficient (with Whitaker model) 3) Use approx transient response model to find the time required to heat outer surface to melting temperature 4) Perform experiment to validate **Note: All calculations done using MATLab

4. Inside Air T=21.3°C Walking Speed V=.9 m/s Ice Cream Properties* K=0.9 w/m°C Melts at T=-5.6°C Initial Temp= -6°C Specific Heat (Cp)=2.75 KJ/kgK 0.1016 meters **Thermophysical properties for ice cream, 2006 ASHRAI Handbook for Refrigeration http://pcfarina.eng.unipr.it/Public/Termofluidodinamica/Utility/Tabelle%20Alimenti.pdf

5.  Time to melt= 7.15 minutes  Convection coefficient= 756 W/mk ( **Fourier number is 0.07 and the model requires 0.1 or greater to be accurate. Use with caution)  Assumptions:  No radiation effects (eating indoors)  Ice cream geometry is approximated as a sphere  Walking is at constant rate  Previously melted ice cream running down the sides does not effect the heat transfer rate  Ice cream is not being eaten during test  Properties of ice cream are accurate

6.  Time to melt=15 minutes (time to outside surface is completely melted) Discussion  The error between the analytical and experiment results could be due to over simplified problem setup. For more accurate results, the effect of the melted ice cream on the un-melted portion needs to be accounted for. Experiment was performed by purchasing chocolate ice cream cone from Cougar Eat and walking around at a steady rate.

7.  Thermophysical properties for ice cream, 2006 ASHRAI Handbook for Refrigeration http://pcfarina.eng.unipr.it/Public/Termofluidodinamica/Utility/Tabelle%20Alimenti.pdf  Infrared temp sensor to measure surface temperature of ice cream  Thermocouple to measure ambient air temperature  Matlab 2014  Fundamentals of Heat and Mass Transfer 7 th edition, Bergman, Lavine, Incropera, Dewitt