Declared series terms

Thermal resistance network

Inputs

Declared hot-side convection coefficienthhW/(m²·K)User-entered hot-side coefficient; no correlation or property calculation is performed.

Declared hot-side convection areaAhUser-entered effective hot-side area.

Declared wall thicknessLUser-entered one-dimensional wall thickness.

Declared wall conductivitykW/(m·K)User-entered conductivity at the stated condition; material selection is excluded.

Declared wall conduction areaAwUser-entered one-dimensional conduction area.

Declared contact resistanceRcK/WOptional user-entered lumped contact term; interface conditions are not inferred.

Declared cold-side convection coefficienthcW/(m²·K)User-entered cold-side coefficient; no correlation or property calculation is performed.

Declared cold-side convection areaAcUser-entered effective cold-side area.

Declared heat rateQ̇User-entered rate used only to calculate the total temperature difference across the declared series network.

Results

Declared hot-side convection resistance

0.0083333

K/W

Declared wall conduction resistance

0.026042

K/W

Declared cold-side convection resistance

0.022222

K/W

Declared series thermal resistance

0.076597

K/W

Temperature difference at declared heat rate

38.299

Rtotal = 1/(hhAh) + L/(kAw) + Rc + 1/(hcAc); ΔT = Q̇Rtotal

A first-pass number, not a code check, certification, or approval. Read the method and its limits below. What this is and is not.

Calculation snapshot

Thermal resistance network

Formula version 1.0.0

Conditions

Declared hot-side convection coefficient	80
Declared hot-side convection area	1.5
Declared wall thickness	25
Declared wall conductivity	0.8
Declared wall conduction area	1.2
Declared contact resistance	0.02
Declared cold-side convection coefficient	30
Declared cold-side convection area	1.5
Declared heat rate	500

Calculated response

Declared hot-side convection resistance	0.0083333 K/W
Declared wall conduction resistance	0.026042 K/W
Declared cold-side convection resistance	0.022222 K/W
Declared series thermal resistance	0.076597 K/W
Temperature difference at declared heat rate	38.299 K

Method

Rtotal = 1/(hhAh) + L/(kAw) + Rc + 1/(hcAc) · ΔT = Q̇Rtotal

Source

DOE-HDBK-1012/2-92, Thermodynamics, Heat Transfer and Fluid Flow, Vol. 2:

Boundaries

One-dimensional declared series path
User-entered convection coefficients
User-entered wall conductivity and contact resistance

This printout is a record of displayed inputs and deterministic formula output. It is not an approval, certification, or engineering conclusion.

Nearby: Sensible heat · Heat-exchanger ΔTlm · Plane-wall conduction · Thermal radiation exchange

Method

Formula, when it applies, and when it does not

Sum hot/cold convection, wall-conduction, and lumped contact terms, then calculate temperature difference at a heat rate.

Rtotal = 1/(hhAh) + L/(kAw) + Rc + 1/(hcAc); ΔT = Q̇Rtotal

When

One-dimensional declared series path
User-entered convection coefficients
User-entered wall conductivity and contact resistance

Don’t

This is a declared, one-dimensional series-resistance arithmetic screen. It does not derive convection coefficients, infer contact conditions, model radiation, phase change, parallel heat paths, thermal bridges, temperature-dependent properties, material selection, service-temperature rating, equipment suitability, safety, or approval.

DOE-HDBK-1012/2-92, Thermodynamics, Heat Transfer and Fluid Flow, Vol. 2