A General Method for the Comparison of Compact Heat Transfer Surfaces

Performance tests were carried out for a microchannel printed circuit heat exchanger (PCHE), which was fabricated with micro photo-etching and diffusion bonding technologies. The microchannel PCHE was tested for Reynolds numbers in the range of 100-850 varying the hot-side inlet temperature between 40 °C-50 °C while keeping the cold-side temperature fixed at 20 °C. It was found that the average heat transfer rate and heat transfer performance of the countercurrrent configuration were 6.8% and 10%-15% higher, respectively, than those of the parallel flow. The average heat transfer rate, heat transfer performance and pressure drop increased with increasing Reynolds number in all experiments. Increasing inlet temperature did not affect the heat transfer performance while it slightly decreased the pressure drop in the experimental range considered. Empirical correlations have been developed for the heat transfer coefficient and pressure drop factor as functions of the Reynolds number.

show abstract

“…The hydraulic diameter and Reynolds number are calculated using the method suggested by Cowell [30] as: = 4…”

Section: Experimental Conditions and Results Analysismentioning

confidence: 99%

Heat Transfer and Pressure Drop Characteristics in Straight Microchannel of Printed Circuit Heat Exchangers

Seo

Kim

et al. 2015

Entropy

View full text Add to dashboard Cite

show abstract

“…the surface and volume goodness as defined by Kays and London [35]. A detailed summary is provided by Cowell [53]. Considering the uncertainty on the specific surface of the foam (as discussed above) and the availability of both heat transfer and pressure drop data for the reference surface (plain tube, see Table. 2) it was selected to compare the performance based on the reference surface: Eq.…”

mentioning

confidence: 99%

Thermo-hydraulic study of a single row heat exchanger consisting of metal foam covered round tubes

T’Joen

Jaeger

Huisseune

et al. 2010

International Journal of Heat and Mass Transfer

113

View full text Add to dashboard Cite

Open cell metal foam is a novel engineering material that offers an interesting combination of materials properties from a heat exchanger point of view such as a high specific surface area, tortuous flow paths for flow mixing and low weight. A new heat exchanger design with metal foams is studied in this work, aimed at low airside pressure drop. It consists of a single row of aluminum tubes covered with thin layers (4-8 mm) of metal foam. Through wind tunnel testing the impact of various parameters on the thermo-hydraulic performance was considered, including the Reynolds number, the tube spacing, the foam height and the type of foam. The results indicated that providing a good metallic bonding between the foam and the tubes can be achieved, metal foam covered tubes with a small tube spacing, small foam heights and made of foam with a high specific surface area potentially offer strong benefits at higher air velocities (> 4 m/s) compared to helically finned tubes. The bonding was done by conductive epoxy glue and was found to have a strong impact on the final results, showing a strong need for a cost-effective and efficient brazing process to connect metal foams to the tube surfaces.

show abstract

“…Based on the measured results, the volumetric flow rate ranged between 3 and 17 L/min, and the Reynolds number ranged between 156 and 921. The hydraulic diameter was calculated using a method proposed by Cowell [10], and the Reynolds number was calculated using Equations (1) and (2).…”

Section: Experimental Conditions and Results Analysismentioning

confidence: 99%

Thermal Characteristics of a Primary Surface Heat Exchanger with Corrugated Channels

Seo

Cho²,

Lee

et al. 2015

Entropy

View full text Add to dashboard Cite

This paper presents the heat transfer and pressure drop characteristics of a primary surface heat exchanger (PSHE) with corrugated surfaces. The PSHE was experimentally investigated for a Reynolds number range of 156-921 under various flow conditions on the hot and cold sides. The inlet temperature of the hot side was maintained at 40˝C, while that of the cold side was maintained at 20˝C. A counterflow was used as it has a higher temperature proximity in comparison with a parallel flow. The heat transfer rate and pressure drop were measured for various Reynolds numbers on both the hot and cold sides of the PSHE, with the heat transfer coefficients for both sides computed using a modified Wilson plot method. Based on the results of the experiment, both Nusselt number and friction factor correlations were suggested for a PSHE with corrugated surfaces.

show abstract

A General Method for the Comparison of Compact Heat Transfer Surfaces

Cited by 53 publications

References 0 publications

Heat Transfer and Pressure Drop Characteristics in Straight Microchannel of Printed Circuit Heat Exchangers

Heat Transfer and Pressure Drop Characteristics in Straight Microchannel of Printed Circuit Heat Exchangers

Thermo-hydraulic study of a single row heat exchanger consisting of metal foam covered round tubes

Thermal Characteristics of a Primary Surface Heat Exchanger with Corrugated Channels

Contact Info

Product

Resources

About