Performance of a novel solar driven ventilation of smoke from moxibustion therapy

Abstract

In this paper, a novel solar driven smoke ventilation system was proposed for the moxibustion therapy. A mathematical model is developed based on heat balance and fluid flow, and the performance of the ventilation system is studied. Sensitivity analyses of solar radiation intensity from 100 to 1000 W/m 2 , collector length from 1 to 10 m, solar system width from 0.5 to 3 m, and chimney width from 0.1 to 0.3 m, and chimney height from 0.5 to 3 m are also performed. For stronger solar radiation, larger collector or higher chimney, the effective heat flux of the solar system increases and the flow rate increases. For the solar radiation of larger than 210 W/m 2 , the velocity at the smoke pipe entrance is larger than the critical velocity of 0.5 m/s. Higher chimney also leads to the increase of the driving force besides receiving more solar radiation. For reaching the pipe entrance velocity of larger than the critical velocity, a solar radiation of larger than 210 W/m 2 , a chimney height of higher than 0.89 m, a collector length of larger than 1.9 m, or a collector width of larger than 0.198 m is needed. The conclusions are obtained under the absent parametric values: the solar radiation intensity of 600 W/m 2 , the chimney height of 2 m, the solar collector length of 8 m, and the widths of solar collector and chimney of 0.25 m. This work lays a solid foundation for application of this solar driven smoke ventilation system to the moxibustion therapy.