The invention relates to a streamlined body for influencing the flow dynamics of a fluid, wherein the streamlined body at least partly corresponds to a rotationally symmetrical airfoil. A streamlined body of this kind can be used in a number of ways, for example as an impact member, as a flow regulator or as a heat exchanger. It also evens out and accelerates flows. It is used to particular advantage in a mixing and reaction chamber for burning fuels.