Microchannel heat-exchanger

Compact heat exchangers MicroChannel heat exchangers Rotor/stator mixers Rotating packed-bed Centrifugal adsorber... 

Tonkovich, A. L. Y, Call, C. J., Jimenez, D. M., Wegeng, R. S., Drost, M. K., MicroChannel heat exchangers for chemical reactors, in Proceedings of the AIChE Symposium Heat Transfer,... 

Figure 24. Integrated active-substrate system proposed by Stanford University. The system includes cantilever bonding, microcapillary die attachment, and microchannel heat exchange on a silicon substrate with active circuits. (Figure was based on reference 167.)...

For microchannel heat exchangers there is a large discrepancy between various experimental reports (45). Recent studies (46) have shown that down to... 

Tonkovich AL et al. MicroChannel heat exchanger for chemical reactors. AICHE Symposium Series 1996 92(310) 119-125. 

Pacific Northwest National Labs (PNNL) designed their microchannel Prox reactor in which reactors are interlayered with the microchannel heat exchanger, so reaction temperature was precisely controlled and high selectivity could be reached. 

Table 7.1 Examples of commercial microchannel heat exchanger applications [16].

Y. Zhao, M. M. Ohadi, R. Radermacher, MicroChannel Heat Exchangers with Carbon Dioxide, final Report for the Air Conditioning and Refrigeration Technology Institute, ARTI-21CR/10020-01. 

Develop efficient thermal management using microchannel heat exchangers and an internal burner. Integrate processes and components to achieve smallest size and most efficient thermal management. 

A microchannel heat exchanger uses rectangular channel of // = 1.26 pm, W = 90 pm, and L = 10 mm at uniform surface heat flux to remove heat from a device. Inlet and outlet pressure respectively are Pj = 210 kPa and = 105 kPa. Air at T) = 20 C is used as cooling fluid. Assuming steady state fully developed conditions, determine the Nusselt number at = 0,0.4, and 0.8. Assume slip flow condition with a = aj= 1.0. 

Consider a microchannel heat exchanger with height H = 1.26 pm, width, w = 90 pm, and length, L = 10 mm. Air at inlet temperature, Tj and inlet pressure 210 kPa enters the channel as coolant fluid. The accommodation coefficient, <7 = af = 1.0. The surface temperature is maintained at = 22 C. Assuming negligible viscous dissipation, calculate the Nusselt number at 4 = 0.2,0.6, and 1.0 for negligible axial conduction and with axial conduction case. 

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