Table 3: Numerical comparison among R-R, R-S, and CDM of clamped-clamped DWCNTs: in columns 3 and 5, the first two dimensionless fundamental frequencies and , with , are reported, while in column 4 the first frequency , with  TPa, is listed.

Method

0R-R22.79336.39441.628
R-S22.41035.783
CDM22.37335.72240.859

0.1R-R21.42734.21239.132
R-S21.13733.750
CDM21.10933.70438.551

0.2R-R18.44929.45833.694
R-S18.30329.225
CDM18.28929.20233.402

0.3R-R15.42224.62528.166
R-S15.35924.525
CDM15.35324.51527.001

0.4R-R12.93420.65223.622
R-S12.90720.609
CDM12.90520.60521.139

0.5R-R11.00517.57120.098
R-S10.99217.552
CDM10.99117.55017.273