Detailed Measurements of Local Heat Transfer Coefficient and Adiabatic Wall Temperature Beneath an Array of Impinging Jets

Abstract

A transient method of measuring the local heat transfer under an array of impinging jets has been developed. The use of a temperature-sensitive coating consisting of three encapsulated thermochromic liquid crystal materials has allowed the calculation of both the local adiabatic wall temperature and the local heat transfer coefficient over the complete surface of the target plate. The influence of the temperature of the plate through which the impingement gas flows on the target plate heat transfer has been quantified. Results are presented for a single in-line array configuration over a range of jet Reynolds numbers.

Flow and heat transfer of confined impingement jets cooling using a 3-D transient liquid crystal scheme

“…The transient liquid crystal method using 1-D heat conduction scheme has been widely employed for jet impingement heat transfer studies; for example, the measurements conducted by Van Treuren et al [16] and Hwang and Cheng [17]. More complete procedures are employed in the three-temperature film cooling problem such as proposed by Vogel et al [18], and Chambers et al [19].…”

Measurement of detailed heat transfer on a surface under arrays of impinging elliptic jets by a transient liquid crystal technique

“…In Fig. 9, the present measurements of mean Nusselt number are compared with the previous data [10,11]. The present data provide information in a relatively lower Re range.…”

“…Detailed heat transfer distributions under arrays of jets impinging on a target plate with dimpled or film hole surfaces were investigated by Treuren et al [10] and Han and his colleagues [11][12][13] using a liquid crystal image technique. They found that the crossflow and the exit flow direction significantly affect the heat transfer distributions on a target surface.…”

Experimental study on the heat transfer under impinging elliptic jet array along a film hole surface using liquid crystal thermograph

“…Attempts have been made to optimize each method in order to obtain effective heat transfer with low pressure loss. Treuren et al [17], Rhee et al [18], Kanokjaruvijit and Martinez-botas [19] and Huang and his colleagues [20,21] investigated detailed heat transfer distributions under arrays of jet impinging on a target plate with dimpled or film hole surfaces. However, their studies only focused on the heat transfer under in-line arrays of jet impinging on a surface.…”