Question

Assume that a surface-grinding operation is being carried out under the following conditions: D = 250 mm, d 0.1 mm, ys 0.5 m/s and V = 50 m/s. These conditions are then changed to the following: D-150 mm, d 0.1 mm, v 0.3 m/s and V-25 m/s, what is the difference in the temperature rise from the initial condition? Assume that C does not change between the two cases. Please give your answer in percent form. For example, "the temperature rise is 50% lower in the second case"

Answer 1

modify temperature is lower than by the 0.196 %

Step-by-step explanation:

given data

D = 250 mm

d = 0.1 mm

v = 0.5 m/s

V = 50 m/s

D = 150 mm

d = 0.1 mm

v = 0.3 m/s

V = 25 m/s

solution

first we get here initial coating condition for temperature change ΔT is

ΔT = A \times D^{1/4} \times d^{3/4}\times \frac{V}{v}^{1/2} ...............1

put here value for both condition

ΔT = A \times 250^{1/4} \times 0.1^{3/4}\times \frac{50}{0.5}^{1/2}

ΔT = 7.07 A ......................2

and

ΔT = A \times 150^{1/4} \times 0.1^{3/4}\times \frac{25}{0.3}^{1/2}

ΔT = 5.68 A .......................3

so here percentage change is

percentage change =
`(5.68 A-7.07 A )/(7.07 A )`

percentage change = - 0.196

so that modify temperature is lower than by the 0.196 %