Storage issues. According to relevant query information, the economic order quantity model, also known as the entire batch interval purchase model EOQ model, is the most commonly used method of ordering goods by most companies. This model is suitable for storage problems where the entire batch is purchased at intervals and no shortage is allowed. That is, the demand for a certain material per unit time is constant D, and the storage capacity gradually decreases at the rate of consumption per unit time D. After time T, the storage capacity drops to zero, at this time, orders are started and the goods arrive immediately. The inventory increases from zero to the highest inventory Q, and then the next storage cycle begins, forming a multi-cycle storage model.