The large-eddy simulation was carried out to research convective heat transfer in the staggered tube bundle of the compact precooler. Besides

the dynamic mode decomposition (DMD) method was used to analyze the coherent structure and statistical characteristic of heat transfer of cross-row tube bundles. Results showed that within the simulated operating range (Re≤6 000)

the flow structure of the front tube bundle exhibited regular shear layer movement and wake vortex shedding. The flow structure of the rear tube bundle was an irregular small-scale vortex structure

and the disorderly flow field of the rear tube bundle was presented. The instantaneous Nusselt number on the surface of the front rows had a relatively fixed wave frequency

while the instantaneous Nu on the back rows had no fixed wave frequency because of the irregular impact of the falling vortex of the front rows. Under the condition of Re=2 600

the entropy production in the bundle mainly came from heat transfer rather than dissipation. The main flow structure contributed to the dissipative entropy production and heat transfer entropy production in the location of the boundary layer and free shear layer on the tube wall. It contributed greatly to the entropy production in the front row tubes

but less to the entropy production in the back row tubes.