Reply To: Total VS Static Temperature for thermal BC of mass flow inlets

[Rob]

Difficult to answer, and there may be maths and engineering to consider. 

For an internal flow we'd likely know the upstream temperature & pressure at near enough rest. For an external flow, we can usually assume the fluid is at rest, but the object is moving (OK, so we move the fluid and not the object but it's all relative). 

So, sketch out the system, including what's moving where. Is the difference in static & total temperature meaningful, and will that alter the solution enough to worry about? You may need to review compressible flow theory (it's been 30 years since I last had to worry about it overly much) and also run models to determine sensitivity.