A crank-angle (*θ*) discretization strategy was chosen to simulate the operation of the harmonic steam engine, as this technique is used throughout the internal combustion engine community to model engine behavior, e.g., see Ref. [16]. This strategy involved developing a series of engine component and behavior submodels that were a function of engine crank angle, and to then link these models together within a loop that incremented the crank angle position over time (e.g., from 0 deg to 720 deg for two full iterations of the crank) and tracked the resulting engine performance. Figure 4 contains a flow chart of this process and the necessary submodels developed to support this modeling strategy. The process starts by fixing the engine configuration based on input parameters selected, and then initializes the model with values for the various model parameters (e.g., cylinder pressure, valve angle, etc.) necessary to solve various differential equations needed to determine the model parameters at the next crank angle step. The key submodels developed were concerned with the position (movement) of the piston, intake valve forces, intake valve dynamics, valve positions, and cylinder pressure. Once the engine model has evaluated all submodels for all crank angle positions of interest, a final submodel would analyze the produced model parameters as a function of crank angle (e.g., work, torque, etc.) and produce values for the output work, power and efficiency of the engine for a given set of input parameters.