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sinfonia:heat_losses_caused_by_drain_pipes_in_the_phpp

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sinfonia:heat_losses_caused_by_drain_pipes_in_the_phpp [2021/09/07 13:09] – nsukhijasinfonia:heat_losses_caused_by_drain_pipes_in_the_phpp [2022/02/15 19:32] (current) – admin
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 <WRAP center 60%> <WRAP center 60%>
-<latex> +$$
 \Large{Q = \varPsi\cdot l \cdot (T_{i} - T_{drain})} \Large{Q = \varPsi\cdot l \cdot (T_{i} - T_{drain})}
-</latex>+$$
 </WRAP> </WRAP>
  
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   * The air inside the pipe may be assumed to have the sewer temperature over its whole length: \\   * The air inside the pipe may be assumed to have the sewer temperature over its whole length: \\
  <WRAP center 60%>  <WRAP center 60%>
-<latex> +$$
 \Large{Q \leq \varPsi\cdot l \cdot (T_{i} - T_{sewer})} \Large{Q \leq \varPsi\cdot l \cdot (T_{i} - T_{sewer})}
-</latex>+$$
 </WRAP> </WRAP>
  
   * The incoming air may be assumed to be heated to room temperature before it leaves the building:  \\   * The incoming air may be assumed to be heated to room temperature before it leaves the building:  \\
   <WRAP center 60%>   <WRAP center 60%>
-<latex> +$$
 \Large{Q \leq \dot m c_{l} \cdot (T_{i} - T_{sewer})} \Large{Q \leq \dot m c_{l} \cdot (T_{i} - T_{sewer})}
-</latex>+$$
 </WRAP> </WRAP>
  
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  <WRAP center 60%>  <WRAP center 60%>
-<latex> +$$
 \Large{T(z) = T_{i} - (T_{sewer} -T_{i}) \cdot e^ { \dfrac{-\varPsi}{\dot m c_{p}} \cdot Z}} \Large{T(z) = T_{i} - (T_{sewer} -T_{i}) \cdot e^ { \dfrac{-\varPsi}{\dot m c_{p}} \cdot Z}}
-</latex>+$$
 </WRAP> </WRAP>
  
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 <WRAP center 60%> <WRAP center 60%>
-<latex>  +$$ 
-\Large{\={T} = T_{i} - (T_{sewer} -T_{i}) \cdot \dfrac{\dot m c_{p}}{\varPsi l} \cdot (e^ { \dfrac{-\varPsi}{\dot m c_{p}} \cdot l} - 1)} +\Large{\overline{T} = T_{i} - (T_{sewer} -T_{i}) \cdot \dfrac{\dot m c_{p}}{\varPsi l} \cdot (e^ { \dfrac{-\varPsi}{\dot m c_{p}} \cdot l} - 1)} 
-</latex>+$$
 </WRAP> </WRAP>
  
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 If the ambient temperatures are higher than the indoor temperatures, the direction of the airflow is reversed. Hot air will fall into the drain vent and proceed down to the sewer. This air initially has the ambient air temperature, not the sewer temperature. In principle, the reduction factor that is used for the calculation of Ψ must be 1 in this case, contrary to  If the ambient temperatures are higher than the indoor temperatures, the direction of the airflow is reversed. Hot air will fall into the drain vent and proceed down to the sewer. This air initially has the ambient air temperature, not the sewer temperature. In principle, the reduction factor that is used for the calculation of Ψ must be 1 in this case, contrary to 
 <WRAP center 60%> <WRAP center 60%>
-<latex> +$$
 \Large{T(z) = \dfrac{T_{i} - T_{drain}}{T_{i} - T_{ambient}}} \Large{T(z) = \dfrac{T_{i} - T_{drain}}{T_{i} - T_{ambient}}}
-</latex>+$$
 </WRAP> </WRAP>
 for the heating case. However, such a distinction would require to provide different Ψ values for each month, or at least for winter and summer. This appears inappropriate with regard to the relative importance of the effect. \\ for the heating case. However, such a distinction would require to provide different Ψ values for each month, or at least for winter and summer. This appears inappropriate with regard to the relative importance of the effect. \\
sinfonia/heat_losses_caused_by_drain_pipes_in_the_phpp.1631012973.txt.gz · Last modified: 2021/09/07 13:09 by nsukhija