Thermal analysis evaluation of direct contact membrane distillation system

In this work, thermal analysis evaluation for a membrane distillation (MD) system is experimentally calculated. Variable feed flow rates and feed temperatures are investigated by calculating the thermal efficiency, gained output ratio and specific energy consumption. The increase in the feed flow rate resulted in increasing the thermal efficiency by 97% and the gained output ratio from 0.31 to 0.60, while the specific energy consumption decreased from 2064 to 1037 kW h/m(3). Enhanced thermal performance can be attributed to the turbulence flow and the short residence time due to the increased flow rate. On the other hand, increasing the feed temperature affected negatively the thermal performance due to heat loss from the membrane cell to the ambient. An increasing in the feed temperature leads to the higher temperature difference between the cell and the ambient that decreased the thermal efficiency up to 34% and the gained output ratio from 0.96 to 0.6, while the specific energy consumption increased from 689 to 1037 kW h/m(3).