raw · papers · ingested 2026-06-19
Experimental Analysis of a Solar Adsorption System Refrigeration Cycle with Silica-Gel/Water Pair
Source: https://www.researchgate.net/publication/348922652
Read from local Zotero full-text PDF (group 5183627 / Joule Heist).
Key findings
- Working pair is silica gel / water in a two-bed adsorption chiller; two adsorbent compartments operate in phase opposition (one desorbing/regenerating via solar hot water while the other adsorbs) to give continuous cold production via condenser and evaporator.
- Tested on the ENERBAT tri-generation platform (gas cogeneration + solar) at Nancy, France, with single-pane flat-plate collectors (total area S = 5.2 m², loss coefficients k1 = 2.437 W/m², k2 = 0.0296 W/m²K²) and four geothermal probes at 100 m depth.
- Measured daily thermal COP of 0.37 (1 April), 0.35 (26 May), and 0.36 (2 June).
- The adsorption machine starts when the hot-water storage tank upper temperature (Tballon_out) reaches the 74 °C setpoint; collector output temperature reached up to 94 °C at 1011 W/m² irradiation; no useful collector heating below ~200 W/m².
- Maximum theoretical collector efficiency was 73.33% at 1022 W/m² global irradiation; first sensor field reached 77 °C at 1010 W/m².
- Geothermal cooling of the adsorber gives roughly half the cycle time of aerothermal (ambient-air) cooling — steady regime reached in 66 min; lower adsorber/condenser cooling temperatures raise adsorption rate and speed condensation.
- With geothermal cooling the desorber power is higher (bed heated from 28.5 °C to 61 °C) and cold production larger; reported power swings ΔQde ≈ 21.07 kW, ΔQref ≈ 15.05 kW, ΔQev ≈ 0.43 kW.
- Operating times tracked solar input: 5 h 40 min, 7 h 40 min, and 6 h 40 min across the three test days.