Industrial Ventilation Design Guidebook by Howard D. Goodfellow download in ePub, pdf, iPad
The supply device with smaller nozzle diameters and fewer nozzles yields rather uniform temperature distribution due to the dominant effect of mixing. In this study, the supply device can be described as an array of round jets on a flat surface attached to a side wall. Increased temperature stratification and less draught distribution are achieved by increasing the nozzle diameter and number of nozzles.
The supply device under consideration has an array of round jets on a curve. The nozzle diameter and number of nozzles play important roles in determining the airflow pattern, temperature field, and draught distribution. Multiple round jets that issue from supply device apertures are combined at a certain distance downstream from the device and behave as a united jet or so-called confluent jets.
The proposed wall confluent jets supply device is compared with a mixing supply device, impinging supply device and displacement supply device. The results show that the impinging confluent jets supply device maintains acceptable thermal comfort in the occupied zone by creating well-distributed airflow during cold and hot seasons.
The computational box and nozzle plate models are used to model the inlet boundary conditions of the nozzle device. The study of the modified wall confluent jets is intended to improve the efficiency of the conventional one while maintaining acceptable thermal comfort in an office environment. The flow behavior is nearly independent of the inlet discharge height for the studied range.
Multiple jets issue from the supply device aperture, in which the supply device is positioned vertically and the jets are directed against a target wall. The flow behavior and ventilation performance of the impinging confluent jets supply device is studied experimentally in an industrial premise. The proposed wall confluent jets supply device provides better overall ventilation performance than the mixing and displacement supply devices used in this study.