首页Home › 科学与工程Science & Engineering
✈️ 马赫数Mach Number Calculator
马赫数 Ma = v / a，当地声速 a = √(γ R T)，空气 γ = 1.4、R = 287.05 J/(kg·K)。Ma < 0.8 亚音速，0.8-1.2 跨音速，> 1 超音速，> 5 高超音速。本地处理。Mach number Ma = v / a with local speed of sound a = √(γ R T); for air γ = 1.4 and R = 287.05 J/(kg·K). Ma < 0.8 subsonic, 0.8-1.2 transonic, > 1 supersonic, > 5 hypersonic. Processed locally.
使用说明与常见问题How-to & FAQ
「马赫数」是什么？What is the Mach Number Calculator tool?
马赫数 Ma = v / a，当地声速 a = √(γ R T)，空气 γ = 1.4、R = 287.05 J/(kg·K)。Ma < 0.8 亚音速，0.8-1.2 跨音速，> 1 超音速，> 5 高超音速。本地处理。Mach number Ma = v / a with local speed of sound a = √(γ R T); for air γ = 1.4 and R = 287.05 J/(kg·K). Ma < 0.8 subsonic, 0.8-1.2 transonic, > 1 supersonic, > 5 hypersonic. Processed locally.
如何使用「马赫数」？How do I use the Mach Number Calculator tool?
填写速度并选择单位，再填写气温和比热比 γ（空气为 1.4），即可得到马赫数 Ma = v ÷ a 以及是亚音速、跨音速还是超音速。结果会随输入实时更新。Enter the speed and its unit, the air temperature and the ratio of specific heats γ (1.4 for air) to get the Mach number Ma = v ÷ a and whether it is subsonic, transonic or supersonic. The result updates as you type.
高度影响？Altitude?
高空更冷，声速更低，同样空速的马赫数更大。Colder air at altitude has a lower speed of sound, so the same true airspeed is a higher Mach number.
能举个计算实例吗？Can you show a worked example?
例如在「马赫数」中填 速度 = 1000，速度单位 = km/h，气温 °C = 15，比热比 γ = 1.4，结果区显示：马赫数：0.8163；当地声速：340.29 m/s = 1,225.1 km/h；流态：跨音速For example, entering Speed = 1000, Speed unit = km/h, Air temperature °C = 15, Ratio of specific heats γ = 1.4 in the Mach Number Calculator gives: Mach number: 0.8163; Local speed of sound: 340.29 m/s = 1,225.1 km/h; Regime: transonic
哪些输入会被检查？Which inputs are validated?
「马赫数」会检查这些输入——「速度」：必须填写，不能为负数；「气温 °C」：必须填写；「比热比 γ」：必须填写，须大于 0；绝对值超过 10¹⁵ 的数也会被拒绝。不符合时结果区显示具体提示，不会给出数字。The Mach Number Calculator checks its inputs — "Speed": required, cannot be negative; "Air temperature °C": required; "Ratio of specific heats γ": required, must be greater than 0; numbers above 10¹⁵ in absolute value are rejected too. When a value fails, the result area names the problem instead of showing a number.
有哪些选项可以调整？What options can I adjust?
「马赫数」的设置：「速度」默认 1000；「速度单位」可选 km/h、m/s、mph、节（默认 km/h）；「气温 °C」默认 15；「比热比 γ」默认 1.4。每次生成结果都按当前设置处理。Settings in the Mach Number Calculator — "Speed" default 1000; "Speed unit": km/h, m/s, mph, knots (default km/h); "Air temperature °C" default 15; "Ratio of specific heats γ" default 1.4. The result always uses the current settings.
计算结果可以用于作业或工程吗？Can I use the results for homework or engineering?
「马赫数」使用教科书标准公式（公式写在说明和常见问题中），适合学习和估算核对；涉及安全的工程设计请以规范和实测为准。The Mach Number Calculator uses standard textbook formulas (given in the description and FAQ), which is good for learning and checking estimates; for safety-critical engineering follow codes and measured values.
「马赫数」免费吗？需要注册吗？Is the Mach Number Calculator free? Do I need an account?
「马赫数」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Mach Number Calculator is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.