NSPipeflow for unsteady simulations

1. The source files of the code used to perform the simulations presented in the paper entitled "Turbulence suppression by cardiac cycle inspired pulsatile driving of pipe flow"
can be found in the folder "src_code_unsteady_pipe_flow_experiments".

2. The instructions needed to install, compile and execute the code can be found in the code's documentation (see folder doc within  the src_code_unsteady_pipe_flow_experiments folder).
Note that the code's documentation does not describe NSPipeFlow (the code used in our simulations) but NSCouette, a code to solve turbulent flow between concentric cylinders. However, both
codes share the same structure and functionalities, and the installation, compilation and execution procedures is in both cases the same. There is also a section by the end of the documentation
where those details which are specific of NSPipeFlow are discussed.

3. The code has been made to simulate the same temporal variation of the Reynolds number as in the experiments. Hence, in the folder where the simulation is going to be executed, there must be
a file called exp_cycle.in including a time series of the Reynolds number that will be read by the code in its initializing phase.

4. The simulation must also be started from an initial condition. To that extent, the information in the coeff_xxxx.info file has to be copied to a restart file (see instructions in the documentation).
The initial condition can be generated by running a simulation at a steady Reynolds number. Here, a solution file corresponding to a turbulent flow state at Re = 3200 is provided, which can be used as
initial condition for the unsteady simulations (We note that this initial condition is not exactly the same as that used in the simulations presented in the paper. Hence, the same exact instantaneous
results cannot be expected. However, average values after several cycles should be the same).






