A spectroscopic analysis has been undertaken for the B-type multiple systems ( excluding those with supergiant primaries ) in the VLT-FLAMES Tarantula Survey ( VFTS ) .
Projected rotational velocities , v _ { e } \sin i , for the primaries have been estimated using a Fourier Transform technique and confirmed by fitting rotationally broadened profiles .
A subset of 33 systems with v _ { e } \sin i \leq 80 km s ^ { -1 } have been analysed using a TLUSTY grid of model atmospheres to estimate stellar parameters and surface abundances for the primaries .
The effects of a potential flux contribution from an unseen secondary have also been considered .
For 20 targets it was possible to reliably estimate their effective temperatures ( T _ { \mathrm { eff } } ) but for the other 13 objects it was only possible to provide a constraint of 20 000 \leq T _ { \mathrm { eff } } \leq 26 000 K – the other parameters estimated for these targets will be consequently less reliable .
The estimated stellar properties are compared with evolutionary models and are generally consistent with their membership of 30 Doradus , while the nature of the secondaries of 3 SB2 system is discussed .
A comparison with a sample of single stars with v _ { e } \sin i \leq 80 km s ^ { -1 } obtained from the VFTS and analysed with the same techniques implies that the atmospheric parameters and nitrogen abundances of the two samples are similar .
However , the binary sample may have a lack of primaries with significant nitrogen enhancements , which would be consistent with them having low rotational velocities and having effectively evolved as single stars without significant rotational mixing .
This result , which may be actually a consequence of the limitations of the pathfinder investigation presented in this paper , should be considered as a motivation for spectroscopic abundance analysis of large samples of binary stars , with high quality observational data .