Design and Optimization of Cross-corrugated Triangular Ducts Towards Reducing CO2 Emission and Improving Energy Efficiency

Abstract

Reducing CO2 emission can effectively control global warming. And energy conservation is the most scientifical and systematical ways to reduce CO2 emissions. The total heat exchangers with membrane core, which consist of cross-corrugated triangular ducts obviously were considered as the most efficient, energy-saving, environmentally friendly air-conditioning heat exchanger. Both simulation and experiment results indicated that, in the cross-corrugated triangular ducts, the flow intensification and the heat transfer efficiency could be significantly improved, which means the energy was saved and the emission of CO2 was reduced. Further studies revealed that the different included angles affected the fluid flow and heat transfer parameters. To disclose the heat transfer enhancement mechanism in the channel, the field synergies had been investigated among velocity gradient, temperature gradient and pressure gradient, which have been validated coincident with the performances of the macroscopic heat transfer parameters. Moreover, the volume-averaged synergy angle took the minimum when the included angle of cross-corrugated triangular ducts took 90° with a Reynolds number of 2000, which was 1-2.3° less than the volume-averaged synergy angles of other included angles with the same Reynolds numbers. For the sake of illustrating the advantage of this channel, four flow channels were compared with the cross-corrugated triangular ducts. And the simulation results reveal that the cross-corrugated triangular ducts have the most outstanding field synergies effect among velocity gradient, temperature gradient and pressure gradient. The total heat exchanger with cross triangular corrugated channel composed of moisture permeable membrane can realize sensible heat and latent heat exchange, and the energy saving is up to 45%. It is supposed that the electricity consumption 76.2 billion kW•h of electricity yearly if this technology is applied in Guangdong, which means bring 1.4 × 10 5 tons of carbon emission reduction or 12% of the target of reducing carbon emissions in Guangdong.