TRENDS IN COP FOR ADSORPTION COOLING CYCLES WITH THERMAL REGENERATION AND FINITE NUMBER OF BEDS

Date

2008-08-14

Author

Baker, Derek Keıth

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

162
views

0
downloads

A thermodynamic model is developed to predict trends in limiting COP of an adsorption cooling cycle with thermal regeneration between n beds, where n is any even number and each bed is spatially isothermal. The results of the model indicate the optimum distribution of beds throughout the cycle to maximize thermal regeneration. Simulations were run for silica gel-water and zeolite-water adsorbent-refrigerant pairs as the maximum bed temperature and the bed's sensible load were varied. For the silica gel-water pair, the exothermic adsorption process occurs at lower temperatures than the endothermic desorption process, which prevents the latent loads from being thermally regenerated. This inability to regenerate latent loads results in a relatively small opportunity to increase COP through thermal regeneration, and this opportunity decreases rapidly with increasing number of beds. Conversely, for the zeolite-water pair much of the exothermic adsorption process occurs over the same temperature range as the endothermic desorption process, which allows a significant portion of the latent loads to be thermally regenerated. This ability to regenerate latent loads results in a much larger opportunity to increase COP through thermal regeneration, and this opportunity decreases much more gradually with increasing number of beds.

Subject Keywords

Adsorption, Cooling, Thermal regeneration

URI

https://hdl.handle.net/11511/54592

Collections

Department of Mechanical Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

Parametric Study and Seasonal Simulations of a Solar Powered Adsorption Cooling System Taylan, Onur; Baker, Derek Keıth; Kaftanoglu, Bilgin (2009-09-03) Models of solar-thermal powered adsorption cooling systems with and without heat recovery developed in TRNSYS and results from steady-periodic and seasonal simulations are presented. A normalized model is presented and used to process the seasonal TRNSYS results to investigate the coincidence between the solar-supplied cooling power and cooling load as the relative sizes of the cooling system and storage are varied. The normalized model yields a seasonal solar fraction and seasonal loss fraction (the excess...
A two-energy equation model for dynamic heat and mass transfer in an adsorbent bed using silica gel/water pair Solmus, Ismail; Rees, D. Andrew S.; Yamali, Cemil; Baker, Derek Keıth (2012-09-01) In this study, the influence of the adsorbent bed dimensions, convective heat transfer coefficient between the cooling fluid and adsorbent bed and the thermal conductivity of the solid adsorbent material on the transient distributions of the solid and gas phase temperature difference, differences in the adsorbate concentration predicted by the instantaneous equilibrium and linear driving force (LDF) models, solid phase temperature, gas pressure and adsorbate concentration inside the adsorbent bed of a solid...
Model based temperature controller development for water cooled PEM fuel cell systems Saygili, Yasemin; Eroğlu, İnci; Kıncal, Serkan (2015-01-05) PEM (proton exchange membrane) fuel cell operation necessitates thermal management to satisfy the requirements of safe and efficient operation by keeping the temperature within a certain range independent of varying load conditions. Heat generation within the fuel cell changes according to the power delivered from the stack, requiring a dynamic control system to remove this excess heat and maintain the desired stack temperature. In this study, a closed loop water circulation strategy is considered and evalu...
Numerical investigation of coupled heat and mass transfer inside the adsorbent bed of an adsorption cooling unit Solmus, Ismail; Rees, D. Andrew S.; Yamali, Cemil; Baker, Derek Keıth; KAFTANOĞLU, BİLGİN (2012-05-01) In this study, the influence of several design parameters on the transient distributions of temperature, pressure and amount adsorbed in the radial direction of a cylindrical adsorbent bed of an adsorption cooling unit using silica gel/water have been investigated numerically. For this purpose, a transient one-dimensional local thermal non-equilibrium model that accounts for both internal and external mass transfer resistances has been developed using the local volume averaging method. For the conditions in...
NUMERICAL ANALYSIS OF CONVECTIVE HEAT TRANSFER OF NANOFLUIDS FOR LAMINAR FLOW IN A CIRCULAR TUBE Kirez, Oguz; Güvenç Yazıcıoğlu, Almıla; KAKAÇ, SADIK (2012-11-15) In this study, a numerical analysis of heat transfer enhancement of Alumina/water nanofluid in a steady-state, single-phase, laminar flow in a circular duct is presented for the case of constant wall heat flux and constant wall temperature boundary conditions. The analysis is performed with a newly suggested model (Corcione) for effective thermal conductivity and viscosity, which show the effects of temperature and nanoparticle diameter. The results for Nusselt number and heat transfer enhancement are prese...

Citation Formats

D. K. Baker, “TRENDS IN COP FOR ADSORPTION COOLING CYCLES WITH THERMAL REGENERATION AND FINITE NUMBER OF BEDS,” 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/54592.