A study of two warehouse inventory dynamism for non-instantaneous deteriorating item with Weibull demand considering trade credit policy

This article deals with a single product inventory stored in two warehouses. Excess items are stored in the rental warehouse $$\left(RW\right)$$ R W after the own warehouse $$(OW)$$ ( O W ) has been filled. Items in $$OW$$ OW are sold only after $$RW$$ RW become empty. Due to the good storage condition in $$RW$$ RW , and in order to maintain the quality of items as well as to reduce the deterioration of items we assume that the storage cost in $$RW$$ RW is very high than the storage cost in $$OW$$ OW . Items in $$RW$$ RW are of having non-instantaneous deterioration nature, whereas in $$OW$$ OW deterioration of items starts at the point of replenishment. As the demand pattern is uncertain, we assume that the demand patterns in $$OW$$ OW and $$RW$$ RW are of Weibull and exponential distributions respectively. An instantaneous replenishment policy is adopted upon reordering and the demands arising at the time of zero items in the inventory are fully backlogged and satisfied at the time of replenishment. We assume that there is a considerable delay in payment by the retailer to a supplier. An explicit expression of the optimum total cost was obtained and the model was numerically illustrated using suitable parameter values. Sensitivity analysis shows the effect of changes in parameter values on the optimal cost of the model.