Experimental investigation and numerical simulation for weakening the thermal fluctuations in a T-junction

•This structure which weakening the thermal fluctuation of internal piping wall in T-junction has not been studied to date.•The numerical results obtained in good agreement with the experimental data.•Reflects the authenticity of large eddy simulation model.

In this work, the mixing processes of hot and cold fluids with and without a distributor are predicted by experiments and numerical simulations using large-eddy simulation (LES) on FLUENT platform. Temperatures at different positions of the internal wall and mixing conditions caused by T-junctions at different times are obtained, then the simulated normalized mean and root-mean square (RMS) temperature, velocity vector and temperature contour for the two structures, namely with and without a distributor, are compared. The results show that, compared with the a T-junction without a distributor, the mixing region of hot and cold water in the T-junction with distributor moves to the middle of the pipe, and the inclusion of the distributor reduces the temperature fluctuations of internal wall noticeably and makes the mixing of hot and cold water more efficient.