Physical Sign | Unit | Description |
---|---|---|
Sv | [m3/h] | Pumping speed foreline pump at pressure pv |
p | [mbar] | Inlet pressure of roots pump |
[mbar] | Pressure difference adjusted at bypass valve | |
S | [m3/h] | Pumping speed at roots inlet flange |
Pa / hPa | Pv / hPa | Sv / (m3 / h) | Q / (hPa · m3/ h) | KΔ | K0 | S1 / (m3 / h) | S2 / (m3 / h) | t / h | t / s |
---|---|---|---|---|---|---|---|---|---|
1,000.0000 | 1,053.00 | 90.00 | 94,770.00 | 1.05 | 94.77 | 0.00490 | 17.66 | ||
800.0000 | 853.00 | 92.00 | 78,476.00 | 1.07 | 98.10 | 0.00612 | 22.04 | ||
600.0000 | 653.00 | 96.00 | 62,688.00 | 1.09 | 104.48 | 0.00827 | 29.79 | ||
400.0000 | 453.00 | 100.00 | 45,300.00 | 1.13 | 113.25 | 0.01359 | 48.93 | ||
200.0000 | 253.00 | 104.00 | 26,312.00 | 1.27 | 131.56 | 0.00652 | 23.45 | ||
100.0000 | 153.00 | 105.00 | 16,065.00 | 1.53 | 7.00 | 160.65 | 321.56 | 0.00394 | 14.18 |
50.0000 | 103.00 | 105.00 | 10,815.00 | 2.06 | 13.00 | 216.30 | 382.20 | 0.00608 | 21.87 |
14.9841 | 56.00 | 110.00 | 6,160.00 | 18.70 | 18.00 | 2,053.33 | 411.10 | 0.00822 | 29.58 |
2.5595 | 10.00 | 115.00 | 1,150.00 | 36.00 | 449.30 | 0.01064 | 38.30 | ||
0.2300 | 1.00 | 105.00 | 105.00 | 50.00 | 456.52 | 0.00670 | 24.13 | ||
0.0514 | 0.30 | 75.00 | 22.50 | 46.00 | 437.39 | 0.00813 | 29.27 | ||
0.0099 | 0.10 | 37.00 | 3.70 | 40.00 | 375.17 | 0.00673 | 24.23 | ||
0.0033 | 0.06 | 15.00 | 0.90 | 39.00 | 270.42 | 0.00597 | 21.51 | ||
0.0018 | 0.05 | 5.00 | 0.25 | 37.00 | 135.29 | ||||
Pump-down time: 344.94 s |
T | Intake gas temperature | [K] |
R | General gas constant | [kJ kmol-1 K-1 |
t | time | [s] |
Pvc | Pressure in vacuum chamber | [Pa] |
mwater | [kg] | |
Mwater | Molar mass of water | [kg mol-1] |
mair | Air mass | [kg] |
Mair | Molar mass of air | [kg mol-1] |
Where:
T | Intake gas temperature | 300 K |
R | General gas constant | 8.314 kJ kmol-1 K-1 |
t | time | 3600 s |
Pvc | Pressure in vacuum chamber | 1000 Pa |
mwater | Water vapor mass | 10 kg |
Mwater | Molar mass of water | 0.018 kg mol-1 |
mair | Air mass | 0.5 kg |
Mair | Molar mass of air | 0.0288 kg mol-1 |
Ak | Condensation surface area | [m2] |
Qwater | Specific enthalpy of evaporation | [Ws kg-1] |
mwater | Water vapor mass | [kg] |
ΔTm | Temperature differential between vapor and condensation surface | [K] |
k | Thermal transmission coefficient | [W m-2 K-1] |
pb | Base pressure | [Pa] |
Ql | Gas flow through leaks and permeation | [Pa m3 s-1] |
Qdes,M | Outgassing from the metal surface | [Pa m3 s-1] |
Qdes,K | Outgassing from the seals | [Pa m3 s-1] |
The vessel has the following data:
V | Vessel volume | 0.2 m3 |
A | Vessel surface | 1.88 m2 |
Ak | ealing surface of the FPM seal | 0.0204 m2 |
Ql | 1.0 ⋅ 10 -9Pa m3 s-1 | |
qdesM | Area-related desorption rate of stainless steel | 2.7 ⋅ 10 -4Pa m3 s-1 m-2 |
qdesK | Area-related desorption rate of FPM | 1.2 ⋅ 10 -4Pa m3 s-1 m-2 |