Condensation heat transfer of R134a and R410A in multiport rectangular microchannels with different aspect ratio

Singh, Varinder; Kukreja, Rajeev; Sehgal, Satbir S.

doi:10.1016/j.ijthermalsci.2022.107696

Cited by 9 publications

(10 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rahman et al [2] found that the heat transfer coefficient is higher at the 30 • C saturation temperature compared to 35 • C for R134a. As given in Table 4, the thermal conductivity of the liquid phase slightly increases with decreasing saturation pressure, which increases the rate of heat transfer from the vapour core to the channel base, as also concluded by [2,4]. Additionally, as stated in [2,14,17], interfacial shear stress plays an important role in the heat transfer coefficient.…”

Section: Two-phase Condensation Testssupporting

confidence: 51%

“…Heat flux from the refrigerant side to the coolant water side through an aluminium block is measured to obtain condensation heat transfer coefficients for each vapour quality; a similar method is followed in the works of [1,4,6]. The assembly of the aluminium block is given in Figure 1.…”

Section: Methodsmentioning

confidence: 99%

“…At 50 kg/m 2 •s, a nearly 67% increase was measured from 45 • C to 40 • C saturation temperatures, whilst a further 48% increase was seen between 40 • C and 35 • C. This outcome is also stated in the work of [3] for the R1234ze(E) refrigerant, in which a gradual increase is shown from 70 • C to 30 • C saturation temperature. For R134a and R410A refrigerants, [4] reported an increase of 3-20% and 2-22% from 40 • C to 30 • C saturation temperatures, respectively. Rahman et al [2] found that the heat transfer coefficient is higher at the 30 • C saturation temperature compared to 35 • C for R134a.…”

Section: Two-phase Condensation Testsmentioning

confidence: 96%

“…As followed by [1,4,6], a fin analysis method is applied to understand the heat transfer rate from the refrigerant to the coolant, where the fin tip is assumed to be adiabatic, as shown in Figure 7. Conduction heat transfer through the aluminium block is assumed to be one-directional.…”

Section: Data Reductionmentioning

confidence: 99%

“…Singh et al [4] investigated R134a and R410A condensation in multiport microchannels with hydraulic diameters of 0.666 mm, 0.823 mm and 1 mm. The authors conducted experiments for mass fluxes between 200 kg/m 2 •s and 600 kg/m 2 •s and for saturation temperatures of 30 • C and 40 • C. The authors found that decreasing the saturation temperature increases the heat transfer coefficient and so does increasing mass flux and vapour quality.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

An Experimental Investigation of R600a Condensation in a Multiport Microchannel

Çoban,

Kuddusi

2024

Micromachines

View full text Add to dashboard Cite

This study aims to provide condensation heat transfer coefficients of R600a (isobutane) refrigerant under mass fluxes between 50 and 98 kg/m2·s at saturation temperatures of 35 °C, 40 °C and 45 °C. Additionally, experiments are conducted with varying inlet vapour quality to understand its effect on the condensation heat transfer measurement. An aluminium multiport microchannel with a hydraulic diameter () of 0.399 mm is used, where a plexiglass cover is mounted on the top of the microchannels to observe the flow conditions. A 1D heat transfer through the aluminium block is assumed, and heat flux through the refrigerant to the coolant is measured to obtain condensation heat transfer coefficients of R600a. The results showed that decreasing saturation temperature and increasing vapour quality increase the condensation heat transfer coefficient. Increasing refrigerant mass flux increases the heat transfer coefficient up to a specific mass flux. It is observed that the effect of inlet vapour quality becomes significant as introduced quality decreases due to increasing fluctuation.

show abstract