without some pictures and clear definition of what you're trying to learn, i'm having a tough time following so i'll throw out a couple of things
1. if the part has a shape prior to bonding, you can model it that way. but if that preshape also comes with stresses, you'll need to create the "prestress" in someway before bonding it.
2. the adhesive can be handled either as a spring or by modeling it.
3. i think its going to be a challenging analysis but most likely nonlinear in sim premium because you need to sequence the steps of the analysis
1. Yeah, I found the "bend tool" to apply the uniform bend across the part. I'm going to ignore any prestress for simplicity sake.
2. I have a modeled version, but was wondering if you could in simulation, apply a mate between the two parts, instead of the adhesive, and apply some of the material specs for stress etc?
I guess the question is how to simulate the now bent PMMA part compressing against the glass until the 20um bend is ~0um. Then run some analysis to find the inverse stress on the connection of the two parts to represent the PMMA unflattening to it's normal state from the glass.
spring sounds like the best fit if you don't want to model the adhesive
i'm not sure about the second part of your requirement (inverse stress)