Question

Consider a reciprocating engine with a crank radius R and connecting rod of length L. The secondary unbalance force for this case is equivalent to primary unbalance force to a virtual crank of ________.

• A. radius $\frac{R^2}{4L}$ rotating at twice the engine speed
• B. radius $\frac{L}{2}$ rotating at twice the engine speed
• C. radius $\frac{R}{4}$ rotating at half the engine speed
• D. radius $\frac{L^2}{4R}$ rotating at half the engine speed

Answer 1

The correct option is A radius $\frac{R^2}{4L}$ rotating at twice the engine speed

Consider a reciprocating engine with a crank radius R and connecting rod of length L. The secondary unbalance force for this case is equivalent to primary unbalance force to a virtual crank of radius $\frac{R^2}{4L}$ rotating at twice the engine speed.