A modular computation method for predicting the flow distribution characteristics in duct system of indirect cooling refrigerator was presented. Firstly

the air duct is divided into several modules according to the position; secondly

the characteristics of air duct resistance and flow rate for each module is obtained; thirdly

the modules are connected into a network according to the actual series or parallel connections of air duct; finally

the flow distribution characteristics is obtained by solving the air duct resistance and flow rate equations. The model was experimentally verified

and the result shows that the deviation of the air flow rate between modular computation method and experiment is within 5%. The modular computation method has the advantages of high accuracy

convenience for modeling and solving

generalization. It is capable to be applied in indirect cooling refrigerator design.