Strange unit of mass flow rate G?

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SUMMARY

The discussion centers on the unit of mass flow rate denoted as G, expressed in kg/(m²·s), which is used in the context of mass flux over a surface area. Participants clarify that G represents mass flow rate per unit area, contrasting it with the conventional mass flow rate unit of kg/s. The conversation highlights the importance of surface area in calculations related to steam flow and condensation, emphasizing that both flow rate and contact surface area are critical factors in determining condensate production.

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DanKot
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Hi
When I was writting my thesis I found in an article, published in International Journal of Heat and Mass Transfer, an unit of mass flow rate G - kg/(m^2*s). Isn´t it wrong? I think that the unit of mass flow rate is kg/s. Would you mind helping me to figure it out? Thanks.
 

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Looks to be the unit of mass flow rate over a given surface area " m^2". Either through an orifice or over a surface. Would that make sense?
 
RogueOne said:
Looks to be the unit of mass flow rate over a given surface area " m^2". Either through an orifice or over a surface. Would that make sense?

That was option I was thinking about. So If I have steam flow in tube, I can just calculate the surface and then I got well-known mass flow rate m - kg/s ?
Thanks
 
DanKot said:
That was option I was thinking about. So If I have steam flow in tube, I can just calculate the surface and then I got well-known mass flow rate m - kg/s ?
Thanks

Looking at the equation again, I take back what I said in the last post. I'll look into it more tomorrow, but I think it may actually have to do with resistance to flow or momentum
 
From the above post it would appear RogueOne has access to the equation(s) in which G and m are used. Could you post those applicable equations; and, maybe where and how they are applied?
 

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The symbol G is usually used to represent mass flux (mass flow rate per unit area).
 
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I have reviewed the abstract, which is of little value in resolving the issue. The only thing that strikes me is the same possibility presented above regarding the inclusion of surface area. From a condensation production standpoint, all other factors being equal, the amount of condensate produced at a given flow rate will be proportional to the available total steam contact area of the flow section; so, in a calculation or equation for condensate production based upon differential temperatures then both the rate of flow and contact surface area would be contributing factors.
 

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