As many have mentioned before verification and validation often come hand in hand, and they sometimes are used interchangeable, but they are different. Combined verification and validation of engineering designs within the product lifecycle directly influence production performance, define product functionality, customer perception of the product, and robustness of the process. The essential framework for design verification and validation, which is lifecycle based consist of four stages: preliminary design stage that sets requirements, digital design domain, product and process development and prototyping phase, and lastly design of production system and a method for the realization of complex processes and products. I attached an article that goes into detail regarding the design verification and validation in product lifecycle

Chris
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.175.5629