This study concerns the heat transfer processes during ice accretion on wires. The steady state heat balance equation assumed to describe the thermodynamics at the surface of a current heated wire subjected to icing i...This study concerns the heat transfer processes during ice accretion on wires. The steady state heat balance equation assumed to describe the thermodynamics at the surface of a current heated wire subjected to icing is obtained by analyzing and computing each terms of heat flux. The surface temperature of wire is derived from the heat balance equation, which gives out a proposed estimation of the current intensity to prevent the wire icing展开更多
Simultaneous free convection above and below a uniformly heated horizontal plate has been widely investigated,both in the case of an isothermal surface,and of a uniformly heated surface,but always assuming only air as...Simultaneous free convection above and below a uniformly heated horizontal plate has been widely investigated,both in the case of an isothermal surface,and of a uniformly heated surface,but always assuming only air as fluid(Pr=0.7).Nevertheless,there are works dealing with horizontal plates whose results show that the Nu dependence on Pr may not be simply expressed by a power law with the same exponent of the Gr one.So it was considered useful to study the Prandtl number influence in the case of the isothermal horizontal strip.Results show that,while for the lower surface of the strip the Nu dependence in Gr can be expressed by a power law with an exponent close to the Gr one,for the upper surface the exponent is sensibly different.Correlating equations related to the investigated situations are proposed.展开更多
文摘This study concerns the heat transfer processes during ice accretion on wires. The steady state heat balance equation assumed to describe the thermodynamics at the surface of a current heated wire subjected to icing is obtained by analyzing and computing each terms of heat flux. The surface temperature of wire is derived from the heat balance equation, which gives out a proposed estimation of the current intensity to prevent the wire icing
文摘Simultaneous free convection above and below a uniformly heated horizontal plate has been widely investigated,both in the case of an isothermal surface,and of a uniformly heated surface,but always assuming only air as fluid(Pr=0.7).Nevertheless,there are works dealing with horizontal plates whose results show that the Nu dependence on Pr may not be simply expressed by a power law with the same exponent of the Gr one.So it was considered useful to study the Prandtl number influence in the case of the isothermal horizontal strip.Results show that,while for the lower surface of the strip the Nu dependence in Gr can be expressed by a power law with an exponent close to the Gr one,for the upper surface the exponent is sensibly different.Correlating equations related to the investigated situations are proposed.
