Optimization of vehicle routing with inventory allocation problems in Cold Supply Chain Logistics

In this research, a new comprehensive mixed integer optimization model combining inventory allocation problem, vehicle routing problem, and cold supply chain (CSC) is formulated, denoted as IVRPCSC Model, to minimize the total cost paid for CSC, including the transportation and inventory costs. As the proposed model is NP-hard, a multi-phases solution approach is developed to solve the model in reasonable computational effort. Results of the proposed solution approach show that it is able to provide solutions with low gaps for the data-sets with different scales in very short computational time compared with the solutions for the same sets provided by commercial solvers, such as CPLEX. At the end, a real case study is solved by the proposed model, and the results show a saving of 9.25% of total distribution cost compared with the current cost paid by the organization.