💨 空气阻力（阻力方程）Drag Equation Calculator

使用说明与常见问题How-to & FAQ

「空气阻力（阻力方程）」是什么？What is the Drag Equation Calculator tool?

F = ½ ρ v² C_d A：ρ 流体密度（空气 1.225 kg/m³），v 速度，C_d 阻力系数，A 迎风面积；并给出克服阻力所需功率 P = F v。本地处理。F = ½ ρ v² C_d A: fluid density ρ (air 1.225 kg/m³), speed v, drag coefficient C_d and frontal area A; plus the power to overcome it, P = F v. Processed locally.

如何使用「空气阻力（阻力方程）」？How do I use the Drag Equation Calculator tool?

填写流体密度（空气约 1.225 kg/m³）、速度、阻力系数和迎风面积，即可得到阻力 F = ½ρv²C_dA 以及克服阻力所需的功率。结果会随输入实时更新。Enter the fluid density (air is about 1.225 kg/m³), speed, drag coefficient and frontal area to get the drag force F = ½ρv²C_dA and the power needed to overcome it. The result updates as you type.

典型 C_d？Typical C_d?

流线型轿车约 0.25-0.3，SUV 约 0.35-0.45，骑行者约 0.9。Sleek cars ≈ 0.25-0.3, SUVs ≈ 0.35-0.45, cyclists ≈ 0.9.

能举个计算实例吗？Can you show a worked example?

例如在「空气阻力（阻力方程）」中填 密度 kg/m³ = 1.225，速度 m/s = 30，阻力系数 C_d = 0.3，迎风面积 m² = 2.2，结果区显示：阻力：363.825 N；所需功率：10.915 kW；速度 km/h：108For example, entering Density kg/m³ = 1.225, Speed m/s = 30, Drag coefficient C_d = 0.3, Frontal area m² = 2.2 in the Drag Equation Calculator gives: Drag force: 363.825 N; Power needed: 10.915 kW; Speed km/h: 108

哪些输入会被检查？Which inputs are validated?

「空气阻力（阻力方程）」会检查这些输入——「密度 kg/m³」、「阻力系数 C_d」、「迎风面积 m²」：必须填写，须大于 0；「速度 m/s」：必须填写，不能为负数；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 Drag Equation Calculator checks its inputs — "Density kg/m³", "Drag coefficient C_d", "Frontal area m²": required, must be greater than 0; "Speed m/s": required, cannot be negative; 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?

「空气阻力（阻力方程）」的设置：「密度 kg/m³」默认 1.225；「速度 m/s」默认 30；「阻力系数 C_d」默认 0.3；「迎风面积 m²」默认 2.2。每次生成结果都按当前设置处理。Settings in the Drag Equation Calculator — "Density kg/m³" default 1.225; "Speed m/s" default 30; "Drag coefficient C_d" default 0.3; "Frontal area m²" default 2.2. 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?

「空气阻力（阻力方程）」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 Drag Equation 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.

「空气阻力（阻力方程）」免费吗？需要注册吗？Is the Drag Equation Calculator free? Do I need an account?

「空气阻力（阻力方程）」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 Drag Equation 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.