BTU/(s·ft²·°F)

BTU per second square foot Fahrenheit

Heat transfer coefficientexact by definition

The BTU per second square foot Fahrenheit is 20441.74879 W/(m²·K), 3600 times the familiar hourly US unit. It belongs to aerothermodynamics and short-duration heating, where per-hour numbers would be absurd: re-entry and rocket nozzle heat transfer are worked per second.

1 BTU/(s·ft²·°F) 20,441.748 W/(m²·K)