Method and system for managed pressure well cementing based on deep wellbore cement slurry system simulation

A method and system for managed pressure well cementing based on deep wellbore cement slurry system simulation. The method comprises the following steps: simulating a hydration reaction of wellbore cement slurry on the basis of basic data and well cementing data of an operating well; calculating in real time the bottom hole pressure in a well cementing process on the basis of the simulation; and adjusting the amount of opening of a choke manifold in order to control wellhead back pressure, such that formation pore pressure < bottom hole pressure < formation fracture pressure. The system comprises a computer-readable medium having a preset program stored thereon, the above method being able to be implemented when the preset program is executed. Bottom hole pressure can be calculated in real time by means of simulating physical or chemical reaction processes of a cement slurry system in a well cementing process, and wellhead pressure is controlled by means of adjusting a choke manifold, such that the bottom hole pressure is constantly maintained in the safe operation window range for a formation, thus preventing the occurrence of complex accidents such as well kicks, gas channeling, or leakage.