  The success of LISA Pathfinder in demonstrating the LISA drag-free
requirement paved the road of using space missions for detecting low-frequency
and middle-frequency GWs. The new LISA GW mission proposes to use arm length of
2.5 Gm (1 Gm = 106 km). The TAIJI GW mission proposes to use arm length of 3
Gm. In order to attain the requisite sensitivity, laser frequency noise must be
suppressed to below the secondary noises such as the optical path noise,
acceleration noise etc. In previous papers, we have performed the numerical
simulation of the time delay interferometry (TDI) for original LISA, ASTROD-GW
and eLISA together with a LISA-type mission with a nominal arm length of 2 Gm
using the CGC 2.7/CGC2.7.1 ephemeris framework. In this paper, we follow the
same procedure to simulate the time delay interferometry numerically for the
new LISA mission and the TAIJI mission together with LISA-like missions of arm
length 1, 2, 4, 5 and 6 Gm. The resulting optical path differences of the
second-generation TDI calculated for new LISA, TAIJI, and LISA-like missions or
arm length 1, 2, 4, 5 & 6 Gm are well below their respective limits which the
laser frequency noise is required to be suppressed. However, for of the first
generation X, Y, and Z TDI configurations, the original requirements need to be
relaxed by 3 to 30 fold to be satisfied. For the new LISA and TAIJI, about one
order of magnitude relaxation would be good and recommended; this could be
borne on the laser stability requirement in view of recent progress in laser
stability. Compared with X, Y and Z, the X+Y+Z configuration does have a good
cancellation of path length differences and could serve as a null string
detection check. We compile and compare the resulting differences of various
TDI configurations due to the different arm lengths for various LISA-like
mission proposals and for the ASTROD-GW mission proposal.
