Modeling and performance of a two-stage collector/regenerator for solar liquid desiccant air conditioning system
A two-stage collector/regenerator (C/R) for the solar liquid desiccant air conditioning system is presented, which adopts a fin-forming absorber plate and where the liquid desiccant flowing process is divided by an isolation board into two stages: regenerating stage I and regenerating stage II. Then a heat and mass transfer mathematical model is established to predict the performance of the two-stage C/R by using calcium chloride as the desiccant. The main results are as follows: (i) The fin-forming absorber plate can increase heat and mass transfer areas and promote turbulence, so that it significantly enhances heat and mass transfer between solution stream and air stream; (ii) Compared with the traditional C/R, a 10 to 25 percent increase in the water evaporation rate for the two-stage C/R can be achieved under the same operating condition.
Experimental Study for a Double-Glazed Forced-Flow Solar Collector/Regenerator
Experimental study of a double-glazed forced-convection solar collector/regenerator for absorption solar cooling is presented. The south facing experimental solar collector/regenerator with 10 deg slope is located at Kaohsiung, Taiwan at 120{degree}19minutesE longitude and 22{degree}34minutesN latitude. The size of the collector is 1 m wide and 7 m long with an effective regeneration area of 0.9 m by 6 m. Previous study for single-glazed forced-convection solar collector/regenerator operated at the same location has shown to have a best day-average efficiency of 17%. In order to raise the system performance, a double-glazed collector/regenerator is constructed such that air can be preheated in the upper channel flow. The preheated air is then conducted into the lower channel where it contacts with the film flow of solar heated lithium-chloride solution and regenerates the solution by carrying out the evaporated water vapor. The preheated air has lower relative humidity but the same humidity ratio since it is sensibly heated. Therefore, the regeneration driving potential is increased. The present study shows that the best day-average efficiency can reach 20% which increases the feasibility of the open-cycle absorption solar cooling system. Effects of controlling parameters on the collector/regenerator performance are studied, and heat and mass transfer correlationsmore » are also presented for design purposes.« less
Adrenocorticotropin insensitivity syndromes.
I. Introduction II. Familial Glucocorticoid Deficiency A. Clinical presentation B. Investigation C. Treatment D. Pathogenesis III. Triple A Syndrome A. Clinical features B. Treatment C. Pathogenesis D. Mapping of triple A syndrome gene E. Candidate genes IV. Acquired ACTH Resistance V. Conclusions