Francis Beaufort scale, decoded as 32–38 mph, or a "moderate Gale". Beaufort, like other patrons of exploration, has had his name given to many geographical places. Among these: Beaufort created the Beaufort cipher. It is a substitution cipher similar to the Vigenère cipher. Francis Beaufort Rear Admiral Sir Francis Beaufort, KCB, FRS, FRGS, FRAS, MRIA (; 27 May 1774 – 17 December 1857) was an Irish hydrographer and officer in the Royal Navy. Beaufort was the creator of the Beaufort Scale for indicating wind force. Francis Beaufort was descended from French Protestant Huguenots, who fled the French Wars of Religion in the
Subsonic and transonic wind tunnel interactions occur (such as shock waves or boundary layer interaction) both Mach and Reynolds number are important and must be properly simulated. Large-scale facilities and/or pressurized or cryogenic wind tunnels are used. With a sonic throat, the flow can be accelerated or slowed down. This follows from the 1D area–velocity equation. If an acceleration to supersonic flow is required, a convergent-divergent nozzle is required. Otherwise: Conclusion: The Mach number is controlled by the expansion ratio formula_11 Subsonic and transonic wind tunnel Low-speed wind tunnels are used for operations at very low Mach number, with speeds in the test section up