An analytical design tool for pin fin sorber bed heat/mass exchanger.

• An analytical solution is proposed for a pin fin heat/mass exchanger sorber bed. • Graphite flake additives in CaCl 2 -silica gel composite sorbents. • ANOVA is utilized to understand the contribution of each parameter on performance. • Parametric study is carried out to examine the effect of key design parameters. • Transient measurement using gravimetric large temperature jump test bed. This paper proposes a novel closed-form analytical model to predict the sorption performance of a pin fin heat/mass exchanger (PF-HMX) prototype, using the Eigenfunction expansion method to solve the governing energy equation. The proposed transient 2-D solution includes all salient thermophysical and sorption properties, sorbent geometry, operating conditions, and the thermal contact resistance at the interface between the sorber bed heat exchanger and sorption composite. An analysis of variance (ANOVA) method is utilized to understand the percentage contribution of each parameter on specific cooling power (SCP) and coefficient of performance (COP). It is shown that the amount of graphite flake, sorbent thickness, and fin radius on one hand and cycle time and graphite flake content on the other have the highest level of contribution to the COP and SCP, respectively. Moreover, a parametric study found that HMX geometry, sorbent properties, and cycle time counteract effects on COP and SCP, which should be optimized simultaneously to build an optimal design. The analytical model was validated successfully using the sorption data from a custom-built gravimetric large temperature jump (G-LTJ) testbed. The experimental results show that the present PF-HMX design with a relatively low mass ratio (MR) can achieve an SCP of 1160 W kg−1 and a COP of 0.68 which are higher than the previously published results in the literature. [ABSTRACT FROM AUTHOR]