Numerical Simulations And Studies On The Natural Ventilation In Highway Tunnel By Solar Chimney

The huge power consumption of tunnel ventilation system, which is becoming a problem, is attracting more and more concern for people. The natural ventilation of highway tunnel has also been one of the key issues in the field of highway tunnel. As a kind of natural ventilation device, solar chimney transforms thermal energy into kinetic energy of air by solar radiation. Then it plays the role of ventilation. In this paper, the natural ventilation in highway tunnel and solar chimney were combined. Researches of solar chimney ventilation for the tunnel ventilation have been carried as follows.At first,put forward a kind of form of highway tunnel ventilation with solar energy chimney, which consists of solar chimney with the shaft. Natural ventilation effect of highway tunnel can be promoted with solar energy. Then, deduce the mathematical formula of solar chimney ventilation quantity and size parameters with the ventilation resistance and excess differential static pressure. With The use of computer simulation, numerical simulation of different size solar chimney was carried out. The simulation results show that the solar chimney with 50-200 m heat collector can produce air pressure which is roughly equal to natural wind ventilation resistance. And by contrast, the formula above was verified At last, a natural ventilation system of solar chimney was set in Lei Jia Po No. 1 tunnel. Through data analysis, combined with numerical simulation, the result of study shows that the system has a good effect of natural ventilation. And the solar chimney improves ventilation in original conditions of pure natural ventilation about one times and in the negative time, the negative pressure generated by the use of solar energy chimney can offset the natural ventilation resistance. Then the improved scheme is put forward. According to the scheme, the ventilation can be improved about 25%-35%.Solar chimney ventilation is fit for the tunnel with abundant solar energy resources. The effect of highway tunnel ventilation can be greatly improved with solar chimney. Promoting the use of it is helpful to realize energy saving and emission reduction target of highway tunnel.