Fuzzy Analogical Gates Approach for Heat Exchangers Networks

This paper presents a systematic method for synthesis of heat exchanger networks, the proposed algorithm consists of three sequential steps to select the optimal approach temperature: i) Estimation of normalized minimum approach temperature, normalized minimum hot utility and normalized minimum cold utility. ii) Fuzzy analogical gates network. iii) Selection of the best weight index. Two analogical gates (symmetric and asymmetric) are employed. The symmetric gate (AND gate) inputs are the normalized minimum approach temperature and normalized hot utility. The asymmetric gate (Invoke gate) inputs are the output of the AND gate and the normalized cold utility. The proposed method has been applied for four problems well-known in published literature. The results of these case studies show that the present strategy is both robust and accurate in finding out global optimum in comparison with previous works, characterized by its simplicity and can be implemented by hand calculations.