An experimental study on volumetric visualization of black oil reservoir models

•Present different strategies to apply volume visualization to irregular hexahedron cells, with a focus on reservoir models.•Investigate including direction ambient occlusion to enhance perception.•Run a set of computational tests comparing required memory, delivered performance, and achieved image quality. [Display omitted] Volume rendering techniques are essential to inspect volume data. In this work, we consider volume rendering for unstructured meshes. We focus on the visualization of black oil reservoir simulation models, represented by irregular hexahedral meshes with geometry distortions and discontinuities. We conduct an experimental study comparing three different strategies to compute the volume integration. The first strategy resamples the model in a regular grid; the second linearizes the model geometry and the variation of the scalar field within a hexahedron cell; the third uses an accurate evaluation of the scalar field at each sample. We compare performance and image quality delivered by each strategy by running a set of experiments with different models. We also investigate the gain in perception applying directional ambient occlusion shading effects. All strategies were entirely implemented on the graphics card.