Empirical investigation of the cooling performance of a new designed Trombe wall in combination with solar chimney and water spraying system

• A Trombe wall with solar chimney and water spraying system is studied empirically.
• Optimum water mass flow rate and water droplet diameter are 10 l/h and 30 μm.
• Most outdoor relative humidity variation effect is on the indoor relative humidity.
• Using water spraying system enhances the thermal efficiency about 30%.

This paper presents an experimental study of a new designed Trombe wall in combination with solar chimney and water spraying system in a test room under Yazd (Iran) desert climate. The Trombe wall area is 50% of that of the southern wall of the building that occupies less space and reduces the implementation costs. The new design of the channel has caused the absorber to receive the solar radiation from three directions. Based on the results, the optimum mass flow rate and the nozzle diameter of the water spraying system has been obtained 10 l/h and 30 μm, respectively. The results indicate that the water spraying system decreases indoor temperature and increases indoor relative humidity by about 8 °C and 17%, respectively. The most effect of outdoor relative humidity variation is on indoor relative humidity, rather than indoor temperature. When outdoor temperature increases, both indoor relative humidity and the difference between indoor and outdoor relative humidity decreases. The results also showed that the stored energy of the Trombe wall plays important role in the air ventilation during non-sunny periods. Lastly, the water spraying system enhances thermal efficiency by approximately 30%.