supergranular scale. These are the same wave vectors that are present in regular hexagons, which have been used in analytical studies of solar convection. At these Fourier components, the bispectrum is positive, consistent with the positive skewness in the data and consistent with supergranules preferentially [[consisting of]{}]{} outflows surrounded by a network of inflows. We use the bispectral estimates to generate synthetic divergence maps that are very similar to the data. This is done by a model that consists of a Gaussian term and a weaker quadratic nonlinear component. Using this method, we estimate the fraction of the variance in the divergence maps from the nonlinear component to be of the order of 4-6%.]{} [We propose that bispectral analysis is useful for understanding the dynamics of solar turbulent convection, for example for comparing observations and numerical models of supergranular flows. This analysis may also be useful to generate synthetic flow fields.]{}

Introduction {#secIntro}
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Supergranular motions are characterized by horizontal velocities of about $300 \,\rm{m}\,\rm{s}^{-1}$ and are coherent features with a length scale of about $30\,\rm{Mm}$ or harmonic degrees of about $l \sim 120$ in the power spectrum [e.g., @Rincon2018 and references therein]. Close to the surface, supergranules are observed 