We present a model for convection in a Navier–Stokes–Voigt fluid when the layer is heated from below and simultaneously salted from below, the thermosolutal convection problem. Instability thresholds are calculated for thermal convection with a dissolved salt field in a complex viscoelastic fluid of Navier–Stokes–Voigt type. The Kelvin–Voigt parameter is seen to play a very important role in acting as a stabilizing agent when the convection is of oscillatory type. The quantitative size of this effect is displayed. Nonlinear stability is also discussed, and it is briefly indicated how the global nonlinear stability limit may be increased, although there still remains a region of potential sub-critical instability, especially when the Kelvin–Voigt parameter increases.

当层从下方加热并同时从下方盐化时，我们提出了Navier–Stokes–Voigt流体中的对流模型，即热对流问题。在Navier–Stokes–Voigt型复杂粘弹性流体中，利用溶解盐场的热对流计算了不稳定性阈值。当对流为振荡型时，Kelvin–Voigt参数被认为在充当稳定剂方面起着非常重要的作用。显示此效果的定量大小。还讨论了非线性稳定性，并简要说明了如何增加全局非线性稳定性极限，尽管仍然存在潜在的亚临界不稳定性区域，尤其是当开尔文-沃格参数增加时。