Attempting to run a relatively complex model with a long water cooling flow path thru a variety of features (ss water traces, rubber tubes, etc.). I have refined the model to reduce cross sectional area changes and abrupt flow direction, however I continue to get the "lid not on boundry between solid and fluid region" message, and the program will not allow the definition of an inlet flow. I would rather not have to simplify the model, as it would not represent the configuration as it should, and I would sacrifice accurate looking results graphics. I am not sure if mesh optimization will necessarily fix the problem, or if the time spent doing that with the complexity of this model would be well spent. If anyone has had to deal with this kind of situation, I would be interested in knowing how it was finally resolved. Thank you.