The “Porcupine”: A Novel High-Flux Absorber for Volumetric Solar Receivers

A new volumetric (directly irradiated) solar absorber, nicknamed Porcupine, is presented. It was tested over several hundreds of hours at the Weizmann institute`s Solar Furnace, using several flow and geometric configurations, at various irradiation conditions. The experiments, which were conducted at a power level of about 10 kW, showed that the new absorber can accommodate different working conditions and provide a convective cooling pattern to match various irradiation flux distributions. The capability of the Porcupine to endure a concentrated solar flux of up to about 4 MW/m{sup 2}, while producing working gas exit temperatures of up to 940 C, was demonstrated. In comparative tests, the Porcupine sustained an irradiation solar flux level about four times higher than that sustained by other volumetric absorbers (foam and honeycomb matrices). Due to its ability to sustain and transport a much higher energy fluxes, the Porcupine yielded twice the power output of the other absorbers while its exit gas temperature was 300--350 C higher. The Porcupine design is highly resistant to thermal stresses development; none of the Porcupine absorbers tested showed any sign of deterioration after hundreds of operating hours, although temperature gradients of several hundreds C/cm developed in some experiments. The basic Porcupinemore » structure provides convective and radiative energy transport between the matrix elements, therefore alleviating the development of flow instabilities; this phenomenon causes local overheating and restricts the operation of other volumetric matrices. A Porcupine absorber was subsequently incorporated into the directly irradiated annular pressurized receiver (DIAPR), where it has been operating flawlessly at an incident flux of several MW/m{sup 2} and temperatures of up to 1,700 C.« less

[1]  Abraham Kribus,et al.  The DIAPR: A High-Pressure, High-Temperature Solar Receiver , 1997 .

[2]  Reiner Buck,et al.  Carbon Dioxide Reforming of Methane in a Solar Volumetric Receiver-Reactor: The CAESAR Project. , 1991 .

[3]  Reiner Buck,et al.  Design and test results of a receiver-reactor for solar methane reforming , 1996 .

[4]  R. Pitz-Paal,et al.  First Experimental Results from the Test of a Selective Volumetric Air Receiver , 1992 .

[5]  Abraham Kribus,et al.  The effect of irradiation directional distribution on absorption in volumetric solar receivers , 1997 .

[6]  Douglas R. Adkins,et al.  Felt-metal-wick heat-pipe solar receiver , 1994 .

[7]  Richard B. Diver,et al.  Solar test of an integrated sodium reflux heat pipe receiver/reactor for thermochemical energy transport , 1992 .

[8]  P. Heller,et al.  Receiver development for a Dish-Brayton system , 1996 .

[9]  Manfred Böhmer,et al.  The Ceramic Foil Volumetric Receiver , 1991 .

[10]  E. A. Fletcher,et al.  Hydrogen- and Oxygen from Water , 1977, Science.

[11]  Gilles Flamant,et al.  Advanced high-temperature two-slab selective volumetric receiver , 1991 .

[12]  W. Meinecke,et al.  PHOEBUS Technology Program Solar Air Receiver (TSA) Operational Experience and Test Evaluation of the 2.5 MW (th) Volumetric Air Receiver Test Facility at the Plataforma Solar de Almeria , 1994 .

[13]  R. D. Rogers,et al.  Fabrication and installation of the Solar Two central receiver , 1996 .

[14]  Robert Pitz-Paal,et al.  Experimental and numerical evaluation of the performance and flow stability of different types of open volumetric absorbers under non-homogeneous irradiation , 1997 .

[15]  Reiner Buck,et al.  Design and Test of Volumetric Receivers for Dish/ Brayton Systems and Solar Methane Reforming , 1994 .

[16]  M. Levy,et al.  Chemical Reactions in a Solar Furnace by Direct Solar Irradiation of the Catalyst , 1989 .

[17]  Robert Pitz-Paal,et al.  Porous Structures for Volumetric Receivers - Comparison of Experimental and Numerical Results. , 1997 .

[18]  Harald Ries,et al.  Inherent limitations of volumetric solar receivers , 1996 .

[19]  C. E. Tyner,et al.  Direct absorption receiver flow testing and evaluation , 1988 .

[20]  Bohn,et al.  Test results from a 10 kW{sub t} solar/natural gas hybrid pool boiler receiver , 1995 .

[21]  R. Buck.  Tests and Calculations for a Volumetric Ceramic Receiver. , 1990 .

[22]  Abraham Kribus,et al.  A High-Pressure Window for Volumetric Solar Receivers , 1998 .

[23]  W. Pritzkow.  Pressure loaded volumetric ceramic receiver , 1989 .

[24]  R. Pitz-Paal.  Evaluation of the Catrec II Receiver Test , 1996 .

[25]  G. Flamant,et al.  High temperature solar gas heating comparison between packed and fluidized bed receivers. I , 1983 .

[26]  J. B. Moreno,et al.  The USDOE Reflux Receiver Development Program , 1992 .