Cooling Air Heat Removed

Overview

Engineering reference data for Cooling Air Heat Removed in heat transfer.

Key Formulas

Fourier's Law

$q = -k \nabla T$

Heat flux proportional to temperature gradient.

Convective Heat Transfer

$Q = hA(T_s - T_\infty)$

Heat transfer between surface and fluid.

Stefan-Boltzmann Law

$q = \varepsilon \sigma T^4$

Radiative heat flux from a surface.

Thermal Resistance

$R_{th} = \frac{L}{kA}$

Resistance to heat conduction.

Variables

Symbol	Description	Unit
$q$	Heat flux	W/m²
$k$	Thermal conductivity	W/(m·K)
$h$	Convection coefficient	W/(m²·K)
$T$	Temperature	K
$\varepsilon$	Emissivity	—
$\sigma$	Stefan-Boltzmann constant	5.67×10⁻⁸ W/(m²·K⁴)

Practical Example

Cooling Air for Cold Storage

When conditioning outside air for refrigerated storage applications, the total heat that must be removed depends on both the temperature differential and the volume of air processed.

Given:

• Outside air temperature: 95°F (35°C)
• Storage room temperature: 50°F (10°C)
• Temperature difference: ΔT = 45°F (25°C)

Result: Approximately 1.5 Btu per cubic foot of air must be removed to cool outside air from 95°F down to 50°F storage conditions.

Unit Conversions

Quantity	Conversion
1 Btu	1,055.06 J (joules)
1 ft³	0.02832 m³

Quick Reference

For storage cooling applications with outside temperatures in the 85°F to 100°F range:

• The heat removal requirement increases as the outside temperature rises
• Higher humidity conditions will require additional latent heat removal beyond the sensible heat values shown
• The 1.5 Btu/ft³ figure represents sensible heat only for the given temperature differential

Note: These values are derived from psychrometric data for standard atmospheric conditions. Actual cooling loads should account for infiltration rates, door openings, product respiration, and equipment heat loads.

References

• Original Source