Evaluation of an earth—air tunnel system for cooling/heating of a hospital complex

Abstract A large earth-air tunnel system meant to provide thermal comfort inside the whole building complex at one of the hospitals in India, has been evaluated. A simple theoretical model is developed to validate the experimental measurements. An 80-m length of the tunnel with a cross-sectional area 0.528m 2 and with an air velocity of 4.89 m s −1 is found to have a cooling capacity of approx. 512 kWh and a heating capacity of 269 kWh. The heating capacity was found to be inadequate for providing the necessary comfort conditions.