In order to study the variation law of flow heat transfer characteristics of turbine blade constricted and expanded serpentine channel

The flow resistance and heat transfer performance of the inlet Reynolds number Re=2~5×104 and the contraction and expansion ratio of s/k=2:5

3:5

4:5 and 5:5 were analyzed by using the method of transient liquid crystal technique and numerical simulation. The results show that the heat transfer capacity of the constricted and expanded serpentine channel and the channel with deflector increases with the decrease of the contraction and expansion ratio. The resistance coefficient of the deflection meandering channel is generally higher than that of the deflector channel

and the resistance coefficient of the deflector channel is basically unchanged with the increase of Reynolds number

and the change range remains at 1%~5%

when Re=2×104 and s/k=5:5

the resistance coefficient of the deflector channel decreases by 59.46% compared with the constricted and expanded serpentine channel. The thermal performance of the deflector channel is stronger than that of the constricted and expanded serpentine channel

and the thermal performance of the deflector channel is higher or too low than the contraction and expansion ratio

the highest thermal performance occurs at Re=2×104

s/k=3:5 The deflector channel TPF=0.87. In summary

the constricted and expanded serpentine channel

has reference value in the design of the inner cooling channel of turbine blades in the future.