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Ventilation effect

  1. Feb 15, 2006 #1
    I want to calculate how much effect in Watts a ventilation system brings into a room. Will it be correct to use the following equation for this:

    \dot Q = \dot V \cdot 0,335 \cdot \left( {T_A - T_O } \right)

    where 0,335 is actually the Cp of air derived from [itex]{{1005} \over {3600}} \cdot 1,2[/itex]
    TA is the temperature the air enters the room with, and TO is the outside temp.

    If the air enters the room with a lower temp than the room, how can the energy needed to heat up this air to room temp be taken into account?
  2. jcsd
  3. Feb 16, 2006 #2


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    I would think that should work, however, check your units. On the left you have watts, or J/s, on the right you have (m^3/s)(J/kgK)(K) giving you...well not what your looking for. I'm pretty sure you need to change your volume flow to mass flow.
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