The impact of a dual-boundary framework on thermodynamic assessment: A comparative exergy analysis of a PWR
Progress in Nuclear Energy, cilt.201, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 201
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.pnucene.2026.106576
- Dergi Adı: Progress in Nuclear Energy
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, Environment Index, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Dual-boundary framework, Energy conversion efficiency, Exergy analysis, Pressurized water reactor (PWR), Sustainable power generation, TESPy simulation
- Yozgat Bozok Üniversitesi Adresli: Evet
Özet
Conventional exergy analyses of Nuclear Power Plants (NPPs) inherently depend on thermodynamic boundary selection, yet its influence on the interpretation and distribution of exergy destruction has not been systematically examined. This study proposes a Dual-Boundary Framework (DBF) for the thermodynamic and exergetic assessment of a conceptual Pressurized Water Reactor (PWR), implemented using the TESPy nonlinear network solver coupled with CoolProp. The model is validated against reference-PWR performance trends before evaluating two complementary exergy boundaries under constant thermal power of 3714.50 MW. The Fission-Based Boundary (Approach 1) employs the theoretical fission pseudo-temperature as the exergy source, yielding an exergetic efficiency equal to the thermal efficiency (35.80%) and total plant exergy destruction of 2344.42 MW, encompassing both intrinsic nuclear degradation and component-level irreversibilities. In contrast, the Average Fuel Temperature-Based Boundary (Approach 2) adopts representative average fuel pellet temperature (Tfp,avg = 800°C) as the finite-temperature heat source, excluding fission-related exergy destruction from the thermodynamic boundary. This yields an exergy input of 2699.82 MW, an exergetic efficiency of 49.25%, and a Carnot efficiency of 72.68%. An ambient-temperature (T0) sensitivity analysis and a criterion-filtered local sensitivity analysis over PSG = 6.8−8.0 MPa, corresponding to approximately Tfp,avg = 799−806°C, demonstrate complementary diagnostic responses of the two exergy boundaries. Approach 1 quantifies overall degradation of nuclear energy into useful work, whereas Approach 2 highlights engineering-domain power-conversion irreversibilities while revealing environmental and fuel-temperature effects on thermodynamic performance. The proposed DBF distinguishes intrinsic nuclear irreversibilities from potentially actionable engineering losses, providing a physically consistent framework for exergy assessment and thermodynamic evaluation of solid-fuel NPPs.