قارن الطرق

	نظرية عنصر الشفرة والزخم	الوزن والتوازن
المجال	هندسة الطيران والفضاء	هندسة الطيران والفضاء
العائلة	Process / pipeline	Process / pipeline
سنة النشأة	1889	1940s
صاحب الطريقة	William Froude, Heinrich Glauert	Aviation engineering
النوع	Analysis method	Analysis method
المصدر التأسيسي	Froude, W. (1889). On the elementary relation between pitch, slip, and propulsive efficiency. Transactions of the Institution of Naval Architects, 30, 94–103.	Federal Aviation Administration (2017). Airplane Weight and Balance Control. Advisory Circular AC 23-8B-1C.
الأسماء البديلة	BEM theory, rotor performance prediction, actuator disk method	W&B, center of gravity, CG analysis
ذات صلة	3	3
الملخص	Blade element momentum theory (BEM) is a fundamental method for analyzing rotor performance by combining blade element aerodynamics with momentum conservation. Developed initially by Froude and refined by Glauert and Leishman, BEM decomposes a rotor into radial blade elements, computes local aerodynamic forces, and sums contributions to predict total thrust, torque, power, and efficiency. BEM is standard for helicopter, wind turbine, and propeller design.	Weight and balance analysis is the process of determining the total weight of an aircraft and the location of its center of gravity (CG) throughout its operational envelope. Essential for aircraft safety and performance, weight and balance ensures that the CG remains within allowable limits (forward and aft) to maintain stable flight and controllability. Regulatory certification requires comprehensive weight and balance documentation for every aircraft configuration.