This study uses stereo-particle image velocimetry to describe the wake behind a multi-wake model at a Reynolds number of $5.64\times {10}^5$ based on the model length $L_x$. All three velocity components are measured in cross-stream planes at various streamwise locations starting from the trailing edge of the model. The time-averaged, three-dimensional flow is reconstructed from the planar measurements, and three important regions in the wake are identified. The near-wake is dominated by a separation bubble that forms immediately downstream of the model. Shear layers, which detach from the sides of the model, morph into a single connected ‘bound vortex’ that stays inside the separation bubble and dominates the flow up to $x/L_x\approx 0.4$. The far-wake is mainly influenced by four corner vortices that originate from the upper and lower rear slant edges. In the near-wake region, the corner vortices enhance the inward mass and momentum transfer in the vertical direction and oppose them in the spanwise direction. As such, they warp the shape of the separation bubble although their overall effect on the internal flow within the separation bubble is minor. In the far wake, they redistribute the momentum in the vertical-spanwise plane. Their induced flow reduces the momentum deficit in the central streamwise-vertical plane relative to off-center planes. It can be concluded that it is the corner vortices which dominate the far-wake and that they remain coherent several body lengths behind the vehicle. Similar to the Ahmed body, the slant angles play a major role on the evolution of the wake which has implications for reducing drag.

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• Turbulence
• Vortex dynamics
• Wakes & jets
• Particle image velocimetry