Joint study describes optimisation of residential air conditioners with smaller diameter copper tubes.

ICA and Shanghai Jiao Tong University (SJTU) conducted joint research on the optimisation of coil designs made with smaller diameter copper tubes. Simulation-based design methods were applied to minimising total system costs of a unit with a nominal cooling capacity of 3450W.

Costs were reduced by 17% compared to systems made with larger diameter tubes.

The design goal was to minimise the total cost (including costs of materials, processes and labour) for manufacturing an air conditioner of a given capacity. The parameters to be optimised included heat exchanger length, fin pitch, number of paths and other physical and geometrical design factors. System cooling capacity did not vary by more than one per cent.

“The simulation-based design method allows for many heat exchanger designs to be explored more efficiently than traditional cut-and-try methods,” explained Wenson Zheng, Deputy Director of Technology for ICA.

The design methodology encompasses a heat-exchanger simulator as well as a knowledge-based evolution method (KBEM). The simulator performs heat exchange calculations to determine system performances based on physical properties and geometrical design parameters, while the KBEM eliminates unfeasible or impractical designs, before the simulations are performed, allowing for a more efficient sampling of the design space.