Heatmap Interpolation

I’m trying to get a smooth heatmap for showing fluid flow. When I use MatPlotLib in Python,
using this code:
im = plt.imshow(fluid.density, cmap=‘hot’, vmax=100, interpolation=‘bilinear’)
I get a heatmap that interpolates the density from a rough 40 by 40 grid to a chart in which the pixels are smoothed across the grid.

When I use this code in Julia with Plots:
heatmap(fluid.density, c=cgrad(:inferno), size=(500, 500), title=“Test Flow”,
it shows the density values in the grid, but with no pixel interpolation.

So my question is: How can I get pixel-level interpolation across a fairly coarse grid in Julia/Plots?

Thanks for any help you can give.