Hello,

for my labwork, I need to express Nm3/h to m3/h. I know that the N of Nm3 stands for Normal, meaning standard temperature and pressure. So, I have used the following expression to calculate the volume in m3.

V2 = P1*V1*T2/(T1*P2)

My manometer gives a flow rate of 15 Nm3/h. So, by using the standard conditions (T1=273.15 K, P1=101325 Pa), I have found for different pressure at 298.15 K the following results :

P2(Pa) 200000 400000 600000 T2=298.15K V1=15m3

V2 (m3) 8.3 4.15 2.77

for example ,V2=101325*15*298.15/(200000*273.15)

I don't understand why the volume decreases when the pressure increases. could you help me please?

for my labwork, I need to express Nm3/h to m3/h. I know that the N of Nm3 stands for Normal, meaning standard temperature and pressure. So, I have used the following expression to calculate the volume in m3.

V2 = P1*V1*T2/(T1*P2)

My manometer gives a flow rate of 15 Nm3/h. So, by using the standard conditions (T1=273.15 K, P1=101325 Pa), I have found for different pressure at 298.15 K the following results :

P2(Pa) 200000 400000 600000 T2=298.15K V1=15m3

V2 (m3) 8.3 4.15 2.77

for example ,V2=101325*15*298.15/(200000*273.15)

I don't understand why the volume decreases when the pressure increases. could you help me please?

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