To study the relationship between sediment concentration and the performance parameters of centrifugal pumps, Jiamakou water supply pumping station with total installed capacity of 30,880 kW was selected to analyze characteristics of the centrifugal pump in this paper. Based on a CFD mixture model, the effects of different sediment concentrations on the movement of solid–liquid two-phase flow and the performance parameters of the centrifugal pump were obtained. Then, fitting equations were established between performance parameters (head, flow rate, shaft power, and efficiency) of the centrifugal pump and sediment concentration at three working conditions (0.8 Q = 2 m³/s, Q = 2.5 m³/s, 1.2 Q = 3 m³/s) by the polynomial least-square method. Calculated values of fitting equations were compared with the measured values in centrifugal pump operation. The results show that, as the sediment concentration increases from 0.1% to 1%, the maximum volume fraction of sediment at blade outlet increased from 0.14% to 1.14%, and the maximum volume fraction of sediment at blade outlet increased from 0.7% to 2.29%. The turbulent kinetic energy inside the centrifugal pump increased from 8.74 m²/s² to 10.78 m²/s². The calculated values of fitting equation are in good agreement with the measured values in centrifugal pump operation, and the maximum errors of head, flow rate, and efficiency are 6.48%, 3.54%, and 2.87%, respectively. Therefore, the reliability of the fitting equations is verified. The research method can provide a reference for the calculation of performance parameters for centrifugal pumps in other water supply pumping stations with sediment-laden flow.

Agro-photovoltaics (APV) or agrivoltaic systems integrate crop cultivation with solar energy production, offering a promising solution through the dual-use of land. This two-year study (2023 and 2024) examined the effects of an APV system on rice production. The results indicated that APV arrays created spatially variable light environments, with shadow lengths following predictable solar azimuth patterns and cloudy conditions mitigating shading effects through enhanced diffuse light. Compared with CK (non-shadow area), inter-panel plots (BP) maintained 77% photosynthetic efficiency and 85.4% plant height, whereas the areas beneath the panel showed a significant decrease in the relative chlorophyll content (SPAD values), photosynthesis rates, and yield. BP plots preserved a 78% fruiting rate through adaptive stomatal regulation, whereas LP zones (directly under the low eave) exhibited 35% higher intercellular CO₂ because of the limited assimilation in shading. Rice yield losses were correlated with shading intensity, driven by reduced panicles and grain filling. Moreover, the APV system achieved a high land equivalent ratio of 148–149% by combining 65–66% rice yield with 82.5% photovoltaics output. Based on the microenvironment created by the APV system, optimal crop types and fertilisation are essential for enhancing agricultural yields and improving land use efficiency.

Agrophotovoltaic (APV) or agrivoltaic (AV) systems, which combine the crop cultivation with solar energy production, emerge as a promising solution by leveraging the dual use of land. This two-year study (2023 and 2024) investigated APV system impacts on rice production. The findings indicated that APV arrays created spatially variable light envi-ronments, with shadow lengths following predictable solar azimuth patterns, cloudy conditions mitigated shading effects via enhanced diffuse light. Compared to CK (non shadow area), inter-panel plots (BP) maintained 77% photosynthetic efficiency and 85.4 % plant height, while beneath panel areas showed significant declines of SPAD values, photosynthesis rate and yield. BP plots preserved 78% fruiting rate through adaptive sto-matal regulation, while LP zones (directly under the low eave) showed 35% higher inter-cellular CO₂ due to limited assimilation in shading. Rice yield losses correlated with shading intensity, driven by reduced panicles and grain filling. In addition, the APV sys-tem achieved high land equivalent ratio of 1.48–1.49, which was combining 65-66 % rice yield with 82.5 % photovoltaic output. Based on the microenvironment created by the APV system, an optimal crop types and fertilization management are essential to enhance ag-ricultural yields and to improve land use efficiency.