Method, device, equipment and medium for predicting water injection turns of fracture-cavity type oil reservoir unit

The invention provides a method, a device, equipment and a medium for predicting the water injection turn of a fracture-vug type reservoir unit, and the method comprises the steps: obtaining the historical dynamic production data of the fracture-vug type reservoir unit in a certain development stage of an oil field, and building a comprehensive declining rate prediction model and a natural declining rate prediction model through mathematical derivation; a relation model between the natural declining rate and the comprehensive declining rate is constructed, and then the total water injection oil increasing amount of a single well is calculated through well fixing tracking; thirdly, according to historical dynamic production data, the water injection oil increasing amount of a single round is obtained, the water injection round of a single well can be obtained according to the total water injection oil increasing amount and the water injection oil increasing amount on the basis of the calculation mode of the wa