Compressional behavior of Persian hand knotted wool carpets using response surface methodology

Abstract

The effects of knot density, pile height, number of ply in pile yarn and pile yarn twist on compressional behavior (compression and compression recovery) of Persian hand knotted wool carpets has been studied. The influence of variables on compression behavior of carpets has been quantitatively analyzed by using response surface methodology based on the Box-Behnken design of experiment. The minimum compression occurs with the combination of minimum values of pile height (10 mm), knot density (5 knots/inch) & number of ply in pile yarn (2 ply), and maximum value of pile yarn twist
(4.5 twists/inch). However the maximum compression recovery is attained with the combination of minimum values of pile height (10 mm) & pile yarn twist ( 3.5 twists/inch), and maximum values of knot density (7 knots/inch) & number of ply in pile yarn (4 ply).