Computational fluid dynamics and fuzzy logic (FL) modeling methods were used to estimate heat transfer and fluid flow characteristics in conical spiral tubes. The effects of coil pitch p and cone angle θ at Reynolds numbers Re of 1500–5500 on flow and heat transfer were investigated. Water with an inlet temperature of 298 K was considered as the working fluid, and a constant wall temperature of 398 K was used in the study. FL was used to predict the Nusselt number and friction factor in conical spiral tubes as functions of Re, θ, and p. FL is an efficient method for predicting complex systems and is a valuable complement to classical hard computing techniques. The purpose of the study was to find a relationship between heat exchanger parameters and performance characteristics. It was also investigated how the FL expert system plays an important role in predicting heat transfer performance.
