Question

Which of the mentioned below is the Grashoff’s formula?

(a) th=D\(\sqrt{\frac{3}{16}\frac{P_{max}}{T}}\)

(b) th=D\(\sqrt{\frac{3}{16}\frac{P_{max}}{\sigma_b}}\)

(c) th=D\(\sqrt{\frac{3}{16}\frac{P_{max}}{BP}}\)

(d) th=D\(\sqrt{\frac{3}{16}\frac{P_{max}}{IP}}\)

This question was addressed to me by my college director while I was bunking the class.

This question is from IC Engine topic in chapter Design of IC Engine Components of Automotive Engine Design

Answer 1

Right choice is (b) th=D\(\sqrt{\frac{3}{16}\frac{P_{max}}{\sigma_b}}\)

Explanation: According to Grashoff’s law formula, the thickness of the piston head is given by, th=D\(\sqrt{\frac{3}{16}\frac{P_{max}}{\sigma_b}}\)

Where D is the bore diameter, Pmax  is maximum gas pressure and σb is the stress on the cylinder head.