I am working on a thermal simulation where half of an object is submerged in hot fluid and the other half remains exposed to a cooler fluid (air). I am assuming that prior to exposure to the hot fluid, the object is at steady state. The analysis is transient. 

Thermal Loads:

Temperature: Initial = 75F on all surfaces

Convection: h = 459 and T = 842 on half the object. (I used a split line cut the object in half)

Somehow, the "cool" side drops to -333F. With no convection, this side should not drop below 75F. I had assumed that SolidWorks treats undefined boundary conditions as insulated.

Note: You can see that there does seem to be an appropriate gradient between the two sides of the object.

See photos; thanks in advance. 

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