We present a model for convection in a Kelvin–Voigt fluid of order one when the layer is heated from below and simultaneously salted from below, a problem of competitive double diffusion since heating from below promotes instability, but salting from below is stabilizing. The instability surface threshold is calculated and this has a complex shape. The Kelvin–Voigt parameters play an important role in acting as stabilizing agents when the convection is of oscillatory type. Quantitative values of the instability surface are displayed. The nonlinear stability problem is briefly addressed.

中文翻译：

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一阶开尔文-沃格特流体的竞争性双扩散对流

当层从下面加热并同时从下面盐化时，我们提出了一种在开尔文-福伊特流体的对流模型，该温度为1阶，这是竞争性双重扩散的问题，因为从下面加热会促进不稳定性，但从下面的盐化却是稳定的。计算不稳定性表面阈值，它具有复杂的形状。当对流为振荡型时，开尔文-沃伊特参数在起稳定剂的作用中起着重要作用。显示不稳定性表面的定量值。非线性稳定性问题得到了简要解决。