Stack Design Pressure Draft For Furnace Calculator

Draft Pressure Formula:

\[ P_{Draft} = 0.0342 \times L_s \times P_{Atm} \times \left( \frac{1}{T_{Ambient}} - \frac{1}{T_{Flue\ Gas}} \right) \]

Stack Height (L_s):

Atmospheric Pressure (P_Atm):

Ambient Temperature (T_Ambient):

Flue Gas Temperature (T_Flue Gas):

Draft Pressure (P_Draft):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Stack Design Pressure Draft?

Draft pressure, also known as chimney draft or flue draft, refers to the pressure difference between the inside and outside of a combustion system or chimney. It is crucial for proper ventilation and efficient operation of furnaces and combustion systems.

2. How Does the Calculator Work?

The calculator uses the draft pressure formula:

\[ P_{Draft} = 0.0342 \times L_s \times P_{Atm} \times \left( \frac{1}{T_{Ambient}} - \frac{1}{T_{Flue\ Gas}} \right) \]

Where:

\( P_{Draft} \) — Draft Pressure (Pa)
\( L_s \) — Stack Height (m)
\( P_{Atm} \) — Atmospheric Pressure (Pa)
\( T_{Ambient} \) — Ambient Temperature (K)
\( T_{Flue\ Gas} \) — Flue Gas Temperature (K)

Explanation: The formula calculates the pressure difference created by the stack effect, which depends on the height of the stack, atmospheric pressure, and the temperature difference between ambient air and flue gases.

3. Importance of Draft Pressure Calculation

Details: Accurate draft pressure calculation is essential for designing efficient combustion systems, ensuring proper ventilation, preventing backdraft, and maintaining optimal furnace performance.

4. Using the Calculator

Tips: Enter stack height in meters, atmospheric pressure in Pascals, and both temperatures in Kelvin. All values must be positive and non-zero.

5. Frequently Asked Questions (FAQ)

Q1: Why is draft pressure important in furnace design?
A: Draft pressure ensures proper exhaust of combustion gases, maintains efficient combustion, and prevents the accumulation of dangerous gases.

Q2: What factors affect draft pressure?
A: Stack height, atmospheric pressure, and temperature difference between ambient air and flue gases are the primary factors.

Q3: What are typical draft pressure values?
A: Typical values range from 10-50 Pa for residential systems to 100-500 Pa for industrial applications, depending on the system design.

Q4: How does temperature affect draft pressure?
A: Higher temperature differences between flue gas and ambient air create stronger draft due to greater buoyancy effects.

Q5: When should draft pressure be measured?
A: During system design, installation, and regular maintenance to ensure proper operation and safety of the combustion system.