Btus (th)/second/square foot/°F to Btus (IT)/second/square foot/°F Converter (Btu (th)/(s·ft²·°F) to Btu/(s·ft²·°F))
Btu (th)/(s·ft²·°F) × 0.9993463 = Btu/(s·ft²·°F)
Calculation: 1 Btu (th)/(s·ft²·°F) × 0.9993463 = 0.9993463 Btu/(s·ft²·°F)
Common Btu (th)/second/square foot/°F to Btu (IT)/second/square foot/°F Calculations
Quick-lookup reference table showing calculated equivalents for standard increments between Btu (th)/second/square foot/°F (Btu (th)/(s·ft²·°F)) and Btu (IT)/second/square foot/°F (Btu/(s·ft²·°F)).
| Conversion & Equivalent Value | Scientific Notation |
|---|---|
| 0.001 Btu (th)/(s·ft²·°F) 0.000999346 Btu/(s·ft²·°F) | 9.993 × 10⁻⁴ |
| 0.01 Btu (th)/(s·ft²·°F) 0.00999346 Btu/(s·ft²·°F) | 9.993 × 10⁻³ |
| 0.1 Btu (th)/(s·ft²·°F) 0.0999346 Btu/(s·ft²·°F) | 9.993 × 10⁻² |
| 0.5 Btu (th)/(s·ft²·°F) 0.499673 Btu/(s·ft²·°F) | 4.997 × 10⁻¹ |
| 1 Btu (th)/(s·ft²·°F) 0.999346 Btu/(s·ft²·°F) | 9.993 × 10⁻¹ |
| 2 Btu (th)/(s·ft²·°F) 1.998693 Btu/(s·ft²·°F) | 1.999 × 10⁰ |
| 5 Btu (th)/(s·ft²·°F) 4.996731 Btu/(s·ft²·°F) | 4.997 × 10⁰ |
| 10 Btu (th)/(s·ft²·°F) 9.993463 Btu/(s·ft²·°F) | 9.993 × 10⁰ |
| 20 Btu (th)/(s·ft²·°F) 19.986926 Btu/(s·ft²·°F) | 1.999 × 10¹ |
| 25 Btu (th)/(s·ft²·°F) 24.983657 Btu/(s·ft²·°F) | 2.498 × 10¹ |
| 50 Btu (th)/(s·ft²·°F) 49.967315 Btu/(s·ft²·°F) | 4.997 × 10¹ |
| 100 Btu (th)/(s·ft²·°F) 99.93463 Btu/(s·ft²·°F) | 9.993 × 10¹ |
| 250 Btu (th)/(s·ft²·°F) 249.836575 Btu/(s·ft²·°F) | 2.498 × 10² |
| 500 Btu (th)/(s·ft²·°F) 499.673149 Btu/(s·ft²·°F) | 4.997 × 10² |
| 1000 Btu (th)/(s·ft²·°F) 999.346298 Btu/(s·ft²·°F) | 9.993 × 10² |
| Reciprocal & Equivalent Value | Scientific Notation |
|---|---|
| 1 Btu/(s·ft²·°F) 1.000654 Btu (th)/(s·ft²·°F) | 1.001 × 10⁰ |
| 5 Btu/(s·ft²·°F) 5.003271 Btu (th)/(s·ft²·°F) | 5.003 × 10⁰ |
| 10 Btu/(s·ft²·°F) 10.006541 Btu (th)/(s·ft²·°F) | 1.001 × 10¹ |
| 50 Btu/(s·ft²·°F) 50.032706 Btu (th)/(s·ft²·°F) | 5.003 × 10¹ |
| 100 Btu/(s·ft²·°F) 100.065413 Btu (th)/(s·ft²·°F) | 1.001 × 10² |
Real-World Context & Everyday Benchmarks
Tap to load into converterTo help contextualize these units in everyday life, science, and engineering, here are verified real-world reference points for Btu (th)/second/square foot/°F (Btu (th)/(s·ft²·°F)) and Btu (IT)/second/square foot/°F (Btu/(s·ft²·°F)):
Btu (th)/second/square foot/°F References:
- High-pressure steam boiler water-wall tube boiling coefficient 0.5 Btu (th)/(s·ft²·°F)
Btu (IT)/second/square foot/°F References:
- Liquid rocket regenerative cooling jacket convective coefficient 0.2 Btu/(s·ft²·°F)
How to Convert Btu (th)/second/square foot/°F to Btu (IT)/second/square foot/°F
Converting Btu (th)/second/square foot/°F (Btu (th)/(s·ft²·°F)) to Btu (IT)/second/square foot/°F (Btu/(s·ft²·°F)) is a core calculation in Heat Transfer Coefficient, which quantifies the proportionality constant between the heat flux and the thermodynamic driving temperature difference. This calculation navigates the boundary between the International Metric System (SI) and British Imperial / US Customary engineering standards. In contemporary metrology, Imperial units are defined in terms of exact SI standards via international agreements—notably NIST SP 811 and the 1959 International Yard and Pound Agreement. Exactly 1 Btu (th)/second/square foot/°F equals 0.999346 Btu (IT)/second/square foot/°F, while 1 Btu/(s·ft²·°F) equals 1.000654 Btu (th)/(s·ft²·°F).
Mathematical Conversion Derivation via Coherent SI Base Unit
Under the International System of Quantities (ISQ), dimensional conversion between non-SI units is rigorously resolved by bridging through the coherent SI base unit (watt per square meter kelvin (W/(m²·K))) without arbitrary rounding:
1 Btu (th)/(s·ft²·°F) = 20428.174538 watt per square meter kelvin (W/(m²·K))1 Btu/(s·ft²·°F) = 20441.537204 watt per square meter kelvin (W/(m²·K))V(Btu/(s·ft²·°F)) = V(Btu (th)/(s·ft²·°F)) × ( 20428.174538 / 20441.537204 ) = V(Btu (th)/(s·ft²·°F)) × 0.999346Value in Btu (IT)/second/square foot/°F = Value in Btu (th)/second/square foot/°F × 0.9993463Direct computational formula applied for standard conversion.Evaluating an input of 120 Btu (th)/second/square foot/°F (Btu (th)/(s·ft²·°F)) produces 119.921556 Btu (IT)/second/square foot/°F (Btu/(s·ft²·°F)). In heavy-duty utility and industrial workloads, 1000 Btu (th)/(s·ft²·°F) equals 999.346298 Btu/(s·ft²·°F).
Inverse check: 1 Btu/(s·ft²·°F) = 1.000654 Btu (th)/(s·ft²·°F).Understanding Btu (th)/second/square foot/°F and Btu (IT)/second/square foot/°F
Btu (th)/second/square foot/°F
Btu (th)/(s·ft²·°F)A Btu (th)/second/square foot/°F (Btu (th)/(s·ft²·°F)) is an imperial and US customary unit for heat transfer coefficient.
Applications & Practical Context
In practical heat transfer coefficient terms, a high-pressure steam boiler water-wall tube boiling coefficient equals 0.5 Btu (th)/(s·ft²·°F).
A physical magnitude of 1 Btu (th)/(s·ft²·°F) corresponds to 20428.174538 W/(m²·K) in standard SI measurement.
1 Btu (th)/(s·ft²·°F) = 20428.174538 W/(m²·K)Btu (IT)/second/square foot/°F
Btu/(s·ft²·°F)A Btu (IT)/second/square foot/°F (Btu/(s·ft²·°F)) is an imperial and US customary unit for heat transfer coefficient.
Applications & Practical Context
In practical heat transfer coefficient terms, a liquid rocket regenerative cooling jacket convective coefficient equals 0.2 Btu/(s·ft²·°F).
A physical magnitude of 1 Btu/(s·ft²·°F) corresponds to 20441.537204 W/(m²·K) in standard SI measurement.
1 Btu/(s·ft²·°F) = 20441.537204 W/(m²·K)Domain Metrology & Engineering Applications
Newton's Law of Cooling (q = h · ΔT)
Rigorously quantified in laboratory and field settings using surface heat flux transducer plates coupled with surface RTD arrays, and wind tunnel boundary layer calorimeters.
Applied across industrial heat exchanger rating, nuclear reactor cooling loop simulation, electronics forced-air cooling, and architectural U-value certification under international metrology standard ISO 80000-5:2019, ASME PTC.
Formulas, conversion coefficients, and base definitions on this page strictly adhere to the ISO 80000-5:2019, ASME PTC and the BIPM SI Brochure (9th Edition). Governed by Newton's Law of Cooling (q = h · ΔT) under ISO 80000 dimensional vector [M T⁻³ Θ⁻¹].
Heat Transfer Coefficient to Convective Flux Bridge (W/m² • kW/m² • BTU/(h·ft²) • cal/(s·cm²))
Calculate Newton’s law of cooling convective heat flux q" = h × ΔT across convective film temperature drops, bridging heat transfer coefficient [M T⁻³ Θ⁻¹] with heat flux [M T⁻³].
q" = h × ΔT
[W/(m²·K)] × [K] → [W/m²]
-
1. Normalize Input to SI Base Unit (W/(m²·K)):
h = 1 Btu (th)/(s·ft²·°F) × 20428.17453832 = 20428.17453832 W/(m²·K) -
2. Apply Engineering Parameter (ΔT):
Selected condition: Forced Air Duct Cooling (ΔT = 25 K) at ΔT = 25 K -
3. Execute Governing Physical Law in SI Units:
q" = h × ΔT = (20428.17453832 W/(m²·K)) × (25 K) = 510704.363458 W/m² -
4. Convert to Standard Engineering Units:
• W/m²: 510704.363458 × 1 = 510704.3635 W/m² (Watts per Square Meter) • kW/m²: 510704.363458 × 0.001 = 510.7044 kW/m² (Kilowatts per Square Meter) • BTU/(h·ft²): 510704.363458 × 0.317 = 161892.464 BTU/(h·ft²) (BTU per Hour Sq. Foot) • cal/(s·cm²): 510704.363458 × 2.3885 × 10⁻⁵ = 12.197964 cal/(s·cm²) (Calories per Second Sq. Cm) • Ly/min: 510704.363458 × 0.001433 = 732.0096 Ly/min (Langley per Minute) • MW/m²: 510704.363458 × 1 × 10⁻⁶ = 0.510704 MW/m² (Megawatts per Square Meter)
| Engineering Substance / Operating Standard | Parameter Value (K) | Reference State / Condition | Typical Industrial & Engineering Application |
|---|---|---|---|
| Natural Air Convection (ΔT = 15 K) | 15 |
ΔT = 15 K (15°C) | Still room air room heating surface delta |
| Forced Air Duct Cooling (ΔT = 25 K) | 25 |
ΔT = 25 K (25°C) | Forced fan ventilation heatsink airflow |
| Forced Liquid Water Cooling (ΔT = 30 K) | 30 |
ΔT = 30 K | Pumped liquid cold plate or engine jacket |
| Nucleate Boiling Heat Transfer (ΔT = 50 K) | 50 |
ΔT = 50 K | Boiler evaporator tube wall boundary |
Frequently Asked Questions
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Physically Coupled Thermodynamics & Heat Converters
Explore interconnected physical dimension converters within the Thermodynamics & Heat cluster (ISO 80000-5:2019).