Model validation


I have a project where I have been monitoring some data for an experiment, (gas flow m3/h and power KW) from a biogas plant pilot. I also have calculated those theoretical values thanks to the known characteristics of the subtract used in the pilot.

I have the monitoring of my data from January to the end of June

I wanted to know how if there is a test (in R for instance) that can help me to validate or not if the theoretical production data were coherent with what had been observed on the pilot.

I thought about doing a Chi 2 test but i don't know if it's relevant and comparing observed and theoretical data did not seem to work as i found for the global monitoring of the gas flow those results X-squared = 397.08, df = 176, p-value < 2.2e-16. (there is also the possibility that i misused the test)

I thought also about doing a Ftest but I'm still trying to figure out how to do it, not sure it would be relevant too :/

Thank you very much for your help

Here is a graph of my data visualization in excel in order to understand what are my monitoring data,
The light blue line in the observed power, the darker one is the theoretical one. The light green line is the observed gas flow and the darker one is the calculated one.