Recent content by engineerings

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    Development thermal boundary layer

    I don't really see how to tackle the problem from now on..
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    Van der waals forces

    Because the interaction forces between gas molecules are less strong than in a liquid. But I don't really see why, image two silica particles immersed in a liquid or in a gas.. I actually think they are larger is a gas than in a liquid. In the van der waals contributions there is the...
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    Van der waals forces

    Are van der waals forces between two molecules stronger in air of in water (as a medium)?
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    Development thermal boundary layer

    I don't really have a specific example, the question was asked me in this way 'does the thermal boundary layer develops faster for a viscous fluid than for an inviscid fluid'? I could make an example: imagine you have a hot flat plate at 40°C and there flows a liquid over it, initially at a...
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    Development thermal boundary layer

    thanks, but this has to do with the hydrodynamic boundary layer, but why does the thermal boundary layer also develops faster for a viscous fluid?
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    Development thermal boundary layer

    Can anyone explain me why the thermal boundary layer develops faster for viscous fluids? I would just say it would develop more slowly because due to high viscosities there are low reynoldsnumbers and thus less turbulence or mixing. This causes a slow homogenization of temperature (assume a...
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    Froude number in vortex formation

    Hi, In a stirred vessels it can occur that a vortex is present which is unwanted because it decreases the mixing. The dimensionless Froude number is a value that can be used to see if the vortex formation is negligible or not. It is defined as Fr=N^2D/g an you can look at it as a ratio of...
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