We present the modeling of data-intensive parallel applications following the synchronous approach. We consider the GASPARD environment, which is dedicated to high-performance system-on-chip (SoC) codesign. Our motivation is to bridge the gap between the GASPARD design approach and the formal validation techniques provided by the synchronous technology. First, we define a synchronous dataflow equational model of GASPARD models. The modeling formalism adopted in GASPARD consists of an extension of the domain-specific language Array-OL. Then, we address correctness issues (e.g., causality and synchronizability analyses) about GASPARD models via their corresponding synchronous descriptions in order to formally validate the original system descriptions.