g love kristin brodie jeff colton colin galbraith bushra makiya tiffany santos
TRANSCRIPT
G Love
Kristin BrodieJeff Colton
Colin GalbraithBushra MakiyaTiffany Santos
Fabrication of Microspheres
Used protocol learned at beginning of semester to fabricate PLGA microspheres
Homogenizer speed: Paraffin: 3.5, 5 Octadecane: 4, 5
Pipette used to separate water and paraffin
Filter used for octadecane (0.22m)
SEM of Microspheres
Paraffin Wax Homogenizer speed
5 Average size:
150m Range: 50 – 300m
SEM of Microspheres (2)
Paraffin Wax Homogenizer speed
3.5 Average size: 200m Range: 50 – 400m
DSC for Octadecane and PEG
Octadecane PEG
Heat Flow Model for a Finger Finger assumed to be a cylinder Power = 2rLq = 2L(T1-T3)/R
R = Fabric Resistance + BL Resistance FR = 1/kc * ln (rc/rw) BLR = 1/(rc*h)
h = 1.22*(T/D)^(1/4) for a horizontal pipe Approximating values:
h~10 W/m2K Power~2.5 W
A hand can be assumed to be a cylinder rhand = 2*rfinger
Heat Transfer Through Gloves
Heating element in the glove (73cm)
Thermistor in and out of the glove
Power: 3.6V Current: 0.55A Weight to reduce air
flow into glove
Heat Flow Results
I*V/A = h (T[in] – T[out]) I = 0.55A V = 3.6V A = 0.05m2
T[in] = 317.42K T[out] = 294.98K
h = 1.765 W/m2K
Event
T [in] T [out]
1 109.9 71.5
2 112.4 71.9
3 112.6 71.6
4 112.5 71.1
5 112.2 71.6
6 112.1 71.7
Avg 111.95
71.57
Data for Heating Element Wires
Ni:Cr 80:20wt%
Ni:Cr:Fe 60:16:24 wt%
Stainless Steel Fe:Cr:Ni 70:19:11 wt%
Starting Diameter (mm)
0.41 0.40 0.375
Area of Wire (in2) 0.00807 1.192e-4 1.7e-4
Suggested Stress (kpsi)
120 74-130 ~95
Length of Graph (in) 19.5 21.7 35
Extension (in) 1.95 2.17 3.5
Max Load (lbs) 24.2 21 17.5
Calculated Stress (kpsi)
121 107.8 102.2
Curve for Ni:Cr 80:20wt%
Ni:Cr 80:20wt%
0
5
10
15
20
25
30
1 3 5 7 9 11 13 15 17 19 21 23 25 27
Distance (inch)
Lo
ad
(lb
s.)
Results Ni:Cr 80:20wt% chosen for large elastic
region Octadecane preferred over PEG for Heat
of crystallization properties Experimental thermal coefficient is
similar to theoretical value
What Will We Do Next? Phase Change Material
Test integrity of PVA Fabricate microspheres of PEG Incorporation of phase change material into fabric DSC of microspheres
Heating Elements Test battery with Prof Ceder Incorporation of thermal switch Choose a fabric to get specific thermal properties