Dew Point Calculator

Dew Point Formula:

\[ \text{Dew Point} = \frac{b \times \alpha}{a - \alpha} \] \[ \alpha = \ln\left(\frac{RH}{100}\right) + \frac{a \times T}{b + T} \]

Dew Point Temperature:

°C

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1. What is a Dew Point Calculator?

Definition: This calculator determines the dew point temperature based on current air temperature and relative humidity.

Purpose: It helps in understanding when moisture will condense from the air, important for HVAC, meteorology, and industrial processes.

2. How Does the Calculator Work?

The calculator uses the Magnus formula:

\[ \text{Dew Point} = \frac{b \times \alpha}{a - \alpha} \] \[ \alpha = \ln\left(\frac{RH}{100}\right) + \frac{a \times T}{b + T} \]

Where:

\( T \) — Air temperature (°C)
\( RH \) — Relative humidity (%)
\( a \) — Constant (17.27)
\( b \) — Constant (237.7 °C)

Explanation: The formula calculates the temperature at which air becomes saturated with water vapor (100% relative humidity).

3. Importance of Dew Point Calculation

Details: Knowing the dew point helps prevent condensation problems, mold growth, and equipment damage in various applications.

4. Using the Calculator

Tips: Enter the current air temperature in °C and relative humidity in % (0-100). The calculator will determine the dew point temperature.

5. Frequently Asked Questions (FAQ)

Q1: What happens when temperature reaches dew point?
A: When air temperature drops to the dew point, water vapor condenses into liquid water (dew, fog, or frost).

Q2: What's a comfortable dew point range?
A: Below 16°C (60°F) is comfortable, 16-18°C (60-65°F) feels humid, above 18°C (65°F) feels oppressive.

Q3: How does dew point differ from humidity?
A: Relative humidity changes with temperature, while dew point is an absolute measure of moisture in the air.

Q4: Can dew point be higher than temperature?
A: No, this would mean supersaturation which is unstable and leads to immediate condensation.

Q5: Why are different constants used in some formulas?
A: The Magnus formula has variations for different temperature ranges (above/below freezing) and accuracy requirements.