Horsepowers/square foot to Btus (th)/second/square foot Converter (hp/ft² to Btu (th)/(s·ft²))
hp/ft² × 0.7072601 = Btu (th)/(s·ft²)
Calculation: 1 hp/ft² × 0.7072601 = 0.7072601 Btu (th)/(s·ft²)
Common Horsepower/square foot to Btu (th)/second/square foot Calculations
Quick-lookup reference table showing calculated equivalents for standard increments between Horsepower/square foot (hp/ft²) and Btu (th)/second/square foot (Btu (th)/(s·ft²)).
| Conversion & Equivalent Value | Scientific Notation |
|---|---|
| 0.001 hp/ft² 0.00070726 Btu (th)/(s·ft²) | 7.073 × 10⁻⁴ |
| 0.01 hp/ft² 0.0070726 Btu (th)/(s·ft²) | 7.073 × 10⁻³ |
| 0.1 hp/ft² 0.070726 Btu (th)/(s·ft²) | 7.073 × 10⁻² |
| 0.5 hp/ft² 0.35363 Btu (th)/(s·ft²) | 3.536 × 10⁻¹ |
| 1 hp/ft² 0.70726 Btu (th)/(s·ft²) | 7.073 × 10⁻¹ |
| 2 hp/ft² 1.41452 Btu (th)/(s·ft²) | 1.415 × 10⁰ |
| 5 hp/ft² 3.5363 Btu (th)/(s·ft²) | 3.536 × 10⁰ |
| 10 hp/ft² 7.072601 Btu (th)/(s·ft²) | 7.073 × 10⁰ |
| 20 hp/ft² 14.145202 Btu (th)/(s·ft²) | 1.415 × 10¹ |
| 25 hp/ft² 17.681502 Btu (th)/(s·ft²) | 1.768 × 10¹ |
| 50 hp/ft² 35.363005 Btu (th)/(s·ft²) | 3.536 × 10¹ |
| 100 hp/ft² 70.72601 Btu (th)/(s·ft²) | 7.073 × 10¹ |
| 250 hp/ft² 176.815025 Btu (th)/(s·ft²) | 1.768 × 10² |
| 500 hp/ft² 353.630049 Btu (th)/(s·ft²) | 3.536 × 10² |
| 1000 hp/ft² 707.260098 Btu (th)/(s·ft²) | 7.073 × 10² |
| Reciprocal & Equivalent Value | Scientific Notation |
|---|---|
| 1 Btu (th)/(s·ft²) 1.413907 hp/ft² | 1.414 × 10⁰ |
| 5 Btu (th)/(s·ft²) 7.069535 hp/ft² | 7.07 × 10⁰ |
| 10 Btu (th)/(s·ft²) 14.13907 hp/ft² | 1.414 × 10¹ |
| 50 Btu (th)/(s·ft²) 70.69535 hp/ft² | 7.07 × 10¹ |
| 100 Btu (th)/(s·ft²) 141.390699 hp/ft² | 1.414 × 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 Horsepower/square foot (hp/ft²) and Btu (th)/second/square foot (Btu (th)/(s·ft²)):
Horsepower/square foot References:
- Liquid rocket combustion chamber regeneratively cooled throat 15 hp/ft²
Btu (th)/second/square foot References:
- Solid rocket motor nozzle graphite throat erosion heat flux 75 Btu (th)/(s·ft²)
How to Convert Horsepower/square foot to Btu (th)/second/square foot
Converting Horsepower/square foot (hp/ft²) to Btu (th)/second/square foot (Btu (th)/(s·ft²)) is a core calculation in Heat Flux Density, which measures the rate of thermal energy transfer radiating or conducting through a unit area per second. 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 Horsepower/square foot equals 0.70726 Btu (th)/second/square foot, while 1 Btu (th)/(s·ft²) equals 1.413907 hp/ft².
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 (W/m²)) without arbitrary rounding:
1 hp/ft² = 8026.646615 watt per square meter (W/m²)1 Btu (th)/(s·ft²) = 11348.931795 watt per square meter (W/m²)V(Btu (th)/(s·ft²)) = V(hp/ft²) × ( 8026.646615 / 11348.931795 ) = V(hp/ft²) × 0.70726Value in Btu (th)/second/square foot = Value in Horsepower/square foot × 0.7072601Direct computational formula applied for standard conversion.To convert 120 Horsepower/square foot (hp/ft²) to Btu (th)/second/square foot (Btu (th)/(s·ft²)): multiply 120 by 0.70726 to get 84.871212 Btu (th)/(s·ft²). At an industrial engineering scale, 5000 hp/ft² converts to 3536.300491 Btu (th)/(s·ft²).
Inverse check: 1 Btu (th)/(s·ft²) = 1.413907 hp/ft².Understanding Horsepower/square foot and Btu (th)/second/square foot
Horsepower/square foot
hp/ft²A Horsepower/square foot (hp/ft²) is an imperial and US customary unit for heat flux density.
Applications & Practical Context
In practical heat flux density terms, a liquid rocket combustion chamber regeneratively cooled throat equals 15 hp/ft².
A physical magnitude of 1 hp/ft² corresponds to 8026.646615 W/m² in standard SI measurement.
1 hp/ft² = 8026.646615 W/m²Btu (th)/second/square foot
Btu (th)/(s·ft²)A Btu (th)/second/square foot (Btu (th)/(s·ft²)) is an imperial and US customary unit for heat flux density.
Applications & Practical Context
In practical heat flux density terms, a solid rocket motor nozzle graphite throat erosion heat flux equals 75 Btu (th)/(s·ft²).
A physical magnitude of 1 Btu (th)/(s·ft²) corresponds to 11348.931795 W/m² in standard SI measurement.
1 Btu (th)/(s·ft²) = 11348.931795 W/m²Domain Metrology & Engineering Applications
Thermal Transmission Flux (q = Q̇ / A)
Rigorously quantified in laboratory and field settings using Schmidt-Boelter heat flux gauges, differential thermopile foil transducers, and calibrated Gardon radiant gauges.
Applied across rocket nozzle combustion chamber analysis, fire resistance testing (ASTM E119), furnace wall heat loss auditing, and hypersonic aerothermal design under international metrology standard ISO 80000-5:2019, ASME PTC 19.3.
Formulas, conversion coefficients, and base definitions on this page strictly adhere to the ISO 80000-5:2019, ASME PTC 19.3 and the BIPM SI Brochure (9th Edition). Governed by Thermal Transmission Flux (q = Q̇ / A) under ISO 80000 dimensional vector [M T⁻³].
Heat Flux Density to Total Thermal Power Bridge (Watts • Kilowatts • Megawatts • BTU/h • Horsepower)
Calculate total continuous heat dissipation power P = q" × A across surface barriers and exchangers, bridging heat flux density [M T⁻³] with thermal power [M L² T⁻³].
P = q" × A
[W/m²] × [m²] → [W]
-
1. Normalize Input to SI Base Unit (W/m²):
q" = 1 hp/ft² × 8026.64661546 = 8026.64661546 W/m² -
2. Apply Engineering Parameter (A):
Selected condition: Industrial Hydronic Radiator Panel (8 m²) at A = 8 m² -
3. Execute Governing Physical Law in SI Units:
P = q" × A = (8026.64661546 W/m²) × (8 m²) = 64213.172924 W -
4. Convert to Standard Engineering Units:
• W: 64213.172924 × 1 = 64213.1729 W (Watts) • kW: 64213.172924 × 0.001 = 64.2132 kW (Kilowatts) • MW: 64213.172924 × 1 × 10⁻⁶ = 0.0642132 MW (Megawatts) • hp: 64213.172924 × 0.001341 = 86.1113 hp (Horsepower (Mechanical)) • PS: 64213.172924 × 0.00136 = 87.3056 PS (Metric Horsepower (PS)) • BTU/h: 64213.172924 × 3.4121 = 219104.44 BTU/h (BTU per Hour)
| Engineering Substance / Operating Standard | Parameter Value (m²) | Reference State / Condition | Typical Industrial & Engineering Application |
|---|---|---|---|
| Residential Window Glazing (4 m²) | 4 |
4.0 m² | Double-pane exterior window glass aperture |
| Industrial Hydronic Radiator Panel (8 m²) | 8 |
8.0 m² | Convective space heating radiator surface |
| Shell & Tube Heat Exchanger (50 m²) | 50 |
50.0 m² | Industrial process fluid cooling bundle |
| Power Boiler Waterwall (200 m²) | 200 |
200.0 m² | Thermal power plant steam generator wall |
Frequently Asked Questions
Related Horsepower/square foot and Btu (th)/second/square foot Conversions
Convert Horsepower/square foot to Other Units
Convert Other Units to Btu (th)/second/square foot
Physically Coupled Thermodynamics & Heat Converters
Explore interconnected physical dimension converters within the Thermodynamics & Heat cluster (ISO 80000-5:2019).