A "float-type" carburetor uses which principle to pull fuel into the airstream?

Question

BlackTom AI · Accepted Answer

Bernoulli's principle explains how an increase in fluid velocity leads to a drop in pressure, which is exactly the Venturi effect used to draw fuel into an airstream. 1. Relevant knowledge points and concepts - Bernoulli's principle: for steady, incompressible, non-viscous flow, P + 1/2 ρ v^2 + ρ g h = constant along a streamline. - Venturi effect: narrowing (throat) forces air to speed up, reducing static pressure there. - Float-type carburetor: a float keeps the fuel bowl at a near-constant level/pressure; jets connect the bowl to the low-pressure region in the venturi so fuel is drawn out when pressure in the throat is lower than in the bowl. 2. Complete reasoning process step by step - Air approaching the carburetor throat has velocity v1 and pressure P1. - As the air passes the venturi throat it accelerates to velocity v2 (v2 > v1). - Apply Bernoulli between upstream and throat: P1 + 1/2 ρ v1^2 = P2 + 1/2 ρ v2^2. - Rearranged: P2 = P1 + 1/2 ρ (v1^2 - v2^2). Since v2 > v1, (v1^2 - v2^2) is negative, so P2 < P1 — pressure at the throat is reduced. 3. Intermediate steps (algebraic) - Start: P1 + 1/2 ρ v1^2 = P2 + 1/2 ρ v2^2 - Solve for P2: P2 = P1 + 1/2 ρ(v1^2 - v2^2) - Because v2 > v1, P2 < P1, producing suction relative to the fuel bowl. 4. Why the correct answer is correct - The pressure drop in the venturi throat (Bernoulli’s effect) creates the suction that pulls fuel from the bowl through the jet into the airstream. The float merely maintains bowl level; the motive force is the low pressure produced by increased air velocity. 5. Why other options are incorrect - Newton’s Third Law (action-reaction) is a general force law and does not explain pressure reduction in accelerated flow that draws fuel. - Boyle’s Law (P·V = constant) describes pressure-volume relationships for a gas at constant temperature, not the dynamic pressure changes in flowing air within a venturi. - Pascal’s Law states pressure applied to a confined fluid is transmitted undiminished, which does not produce localized suction from increased flow speed. 6. Conclusion - The float-type carburetor uses Bernoulli’s Principle (Venturi effect) to pull fuel into the airstream. This matches the provided correct answer: Bernoulli's Principle (Venturi effect).

A "float-type" carburetor uses which principle to pull fuel into the airstream?单项选择题

类似问题

On what scientific principle does an aircraft carburetor function?

A carburetor operates primarily on which physical principle?

Which statement concerning Bernoulli's principle is true?

Which statement concerning Bernoulli's principle is true?

Which region around the aircraft's wing in the figure has the highest pressure?

Bernoulli’s equation holds only for _____________

The aircraft fly based on which principle _________

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单