Heat transfer behaviour of a dilute impinging air-water mist jet at low wall temperatures. (August 2017)

• Record Type: Journal Article
• Authors: Quinn, C.; Murray, D.B.; Persoons, T.
• Is Part Of: International journal of heat and mass transfer. Volume 111(2017)
• Page Start: 1234
• Page End: 1249
• Publication Date: 2017-08
• Subjects: Impinging mist jet -- Low wall temperatures -- Heat transfer -- Liquid film behaviour -- Droplet dynamics -- Shadowgraph imaging; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2017.04.098
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Air-water mist non-boiling heat transfer measurements are presented. Shadowgraph flow imaging is performed to determine mist jet droplet properties. High-speed imagery of the surface liquid behaviour is obtained. The heat transfer mechanisms are linked to the surface liquid morphology. Abstract: This paper presents experimental work on the heat transfer characteristics of a dilute impinging air-water mist jet. Time-averaged heat transfer measurements are reported, as well as simultaneously obtained high-speed shadowgraph imaging flow visualisation and heat transfer measurements; images of the mist jet impingement and the liquid film that forms on the impingement surface are also included. It is determined that the surface liquid morphology varies with mist loading fraction, and that the heat transfer behaviour of the mist jet reflects these changes. Intermittent thermal disturbance caused by the impingement of the mist jet droplets is proposed as the dominant heat transfer mechanism when the mist loading fraction is very low; as the mist loading fraction increases, evaporation from the surface liquid film and convective cooling due to the film flow become more significant.