Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Speed Meters Per Second (m/s)

Required number input.

Sound Speed Meters Per Second (m/s)

Required number input.

Mach number as flow speed divided by local speed of sound; no constant-speed-of-sound approximation. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Mach Number

The resulting mach number returned as a number.

• Lift, drag, Mach, and wing relations depend on air properties, Reynolds and Mach numbers, geometry, angle of attack, configuration, compressibility, ground effect, and validated aerodynamic coefficients. Simple coefficients should not be extrapolated beyond their source data.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Reynolds Number

  Reynolds number for internal flow from density, mean speed, hydraulic diameter and dynamic viscosity.

• Belt Drive Speed Ratio

  Ideal no-slip driven-to-driver pulley speed ratio from pitch diameters.

• Cavitation Number

  Cavitation number (p−pv)/(½ρv²) using local absolute pressure and vapor pressure.