This work describes an analytic model for evaluation of expected effects of the use of ceramic materials in the construction of rocket engine thrust chambers. An engine of a thrust level around 1500 kN is defined and analyzed. The engine analysis makes use of the DLR tool LRP, which calculates sequentially the changes of fluid properties within the components of a rocket engine. Iteratively the solution fulfilling specific constraints is reached. Varied parameters are among others: chambers mixture ratio, chamber pressure, expansion ratio and coolant mass flow. This report describes the assumptions on which the model is based and lists the equations and methods used to represent the relevant relations of physics