How does the opening degree of the induced draft fan affect negative pressure?
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-28 to -38 indicates an increase; just looking at the numbers, the blower valve is opened wider – negative pressure? What happens to the negative pressure when the blower valve is reduced? And how does it change when the exhaust fan valve is opened wider or narrower? Thank you
Is it all because the valves are opened wider, reducing the negative pressure?
Is it all because the valves are opened wider, reducing the negative pressure?
The blower valve is opened, reducing the negative pressure. The induced draft fan valve is opened wider, increasing the negative pressure.
When the blower valve is opened, the negative pressure decreases and the oxygen content increases. When the exhaust fan valve is opened wider, the negative pressure increases, and the smoke exhaust temperature may rise.
The blower is generally used to control the oxygen content, while the exhaust fan is used to control the negative pressure; however, even when the negative pressure is the same, the opening degrees of the blower and the exhaust fan need not be identical.
Let’s see if it’s better to determine the reference point first; when the pressure in front of the fan inlet valve remains constant, opening the fan inlet valve increases the negative pressure (vacuum level) at the fan inlet, while closing it reduces it. This refers to the conditions at the inlet valve of the fan. If the pressure behind the fan inlet valve is kept constant, increasing the fan inlet valve size reduces the negative pressure (vacuum level) at the fan inlet; conversely, it increases. The key is to determine where the measurement point should be located, whether in front of the fan’s inlet valve or behind it. Once the reference point is clear, it can be understood.
When the blower valve is opened, the pressure decreases (in absolute terms); when the valve is closed, the pressure increases. Increased pressure (absolute value). The operation of the exhaust fan is the opposite of the above
The blower valve is opened, reducing the negative pressure. The induced draft fan valve is opened wider, increasing the negative pressure
The induced draft fan is proportional to negative pressure, while the blower is inversely proportional to negative pressure. . .