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This experiment was conducted to assemble and test a cooling system operating with a thermoelectric cooling system (TEC) used to preserve crops and agricultural products from April 14 to June 24, 2021 AD. The study included a test of adding Heat Sink to the cold side of the thermoelectric cooling plates (TEC) with two levels (without heat sink (A1) and with heat sink (A2)) inside the system. 6 cooling models (TEC) were used with 6 heat sinks distributed in the form of two groups, and each group includes three cooling model (TEC). The following characteristics were measured (internal temperature (Tin), temperature difference (∆T), relative humidity (RH), time required to cool (t), cooling capacity (Qc) and Coefficient of Performance (COP). The results reveated that the presence of Heat Sink (A2) was superior than without (A1) in the following characteristics: It gave the lowest temperature inside the system 6.55Cº by 35% over treatment (A1), and pointed the highest (∆T, RH, t, Qc and COP) by (24.19 Cº, 82.32% , 43.73W and 19.87%) respectively. All these obtained results give with a cooling time 4.6h which was higes about 14% than (A1). Where the electrical capacity used 220W.

Lakes significantly influence local climate, yet a systematic assessment of their cooling effect across diverse regions remains limited. This study develops a multi‐metric (spatial extent, magnitude, and efficiency) framework to evaluate the spatiotemporal patterns of Lake Cooling Capacity (LCC) for 265 major Chinese lakes from 1980 to 2022. Results show that Chinese lakes exert substantial cooling on summer daytime maximum temperatures, with a mean extent of 27.5 km, a magnitude of 1.03°C, and an efficiency of 0.46°C/10 km. LCC efficiency shows spatially asymmetric trends, intensifying on the Tibetan Plateau but weakening in the eastern plains. Random forests analysis reveals that albedo is the dominant driver of temporal variability, while depth and surrounding topography are the primary spatial controls. These findings underscore the critical role of lakes in mitigating regional heat extremes and highlight the necessity of incorporating lake‐climate feedback into climate adaptation.

The purpose of this study is to determine the performances of luffa and greenhouse shading netting (which can be used as alternatives to commercial cellulose pads, that are popular for cooling greenhouses), the contribution of external shading to the evaporative cooling performance, and the energy consumption of the direct evaporative cooler. In this experiment, eight different applications were evaluated: natural ventilation (NV), natural ventilation combined with external shading net (NV + ESN), cellulose pad (CP), cellulose pad combined with external shading net (CP + ESN), luffa pad (LP), luffa pad combined with external shading net (LP + ESN), shading net pad (SNP), and shading net pad combined with external shading net (SNP + ESN). The cooling efficiencies of CP, CP + ESN, LP, LP + ESN, SNP, and SNP + ESN were found to be 37.6%, 45.0%, 38.9%, 41.2%, 24.4%, 29.1%, respectively. Moreover, their cooling capacities were 2.6 kW, 3.0 kW, 2.8 kW, 3.0 kW, 1.7 kW, 2.0 kW, respectively. The system water consumption values were 2.9, 3.1, 2.8, 3.2, 2.4, 2.4 l h−1, respectively. The performance coefficients of the system were determined to be 10.2, 12.1, 11.3, 11.9, 6.6, 7.8. The system’s electricity consumption per unit area was 0.15 kWh m−2. As a result of the study, it was determined that commercially used cellulose pads have advantages over luffa and shading net materials. However, luffa pads can be a good alternative to cellulose pads, considering their local availability, initial cost, cooling efficiency, and capacity.

The paper introduces the artificial intelligence (AI) approach as a general method for the design and optimization study of heat exchangers. Genetic Algorithms (GA) and Artificial Neural Networks (ANN) are applied in the paper. An AGENN model, combining Genetic Algorithms with Artificial Neural Networks, was developed and validated against the desired data on a large falling film evaporator. A broad range of operating conditions and geometric configurations are considered in the study. Four kinds of tubes are deliberated, including plain and enhanced tubes. Different tube pass arrangements, i.e., top-to-bottom, bottom-to-top, and side-by-side, are discussed. Finally, the effects of liquid refrigerant mass flow rate, as well as the number of flooded tubes on the performance of the evaporator, are analyzed. The total heat transfer rate of the evaporator, predicted by the model, is in good agreement with the desired data; the maximum error is lower than ±3%. The highest heat transfer rate of the evaporator is 1140.01 kW and corresponds to Turbo EHP tubes, and bottom-to-top tubes pass arrangements, which guarantee the best thermal energy conversion. The presented approach can be referred to as a complementary technique in heat exchanger design procedures, besides the common rating and sizing tasks. It is an effective and alternative method for the existing approaches, considering the complexity of analytical and numerical techniques as well as the high costs of experiments.

The paper presents the research results on the impact of the non-azeotropic mixture refrigerant (R410A) charging process on the cooling capacity of the residential air conditioning (RAC) system through experimental procedures. The RAC system was installed to experiment with two cases that commonly occur in reality regarding the refrigerant charging process. Based on the experimental data and subsequent calculations performed using EES software, the study the liquid refrigerant charging method enhances the specific cooling capacity and coefficient of performance (COP) by 13.137 kJ/kg and 0.404, respectively, compared with the vapor charging method, under the condition of an initially empty system. From there, the authors recommend the process of charging the non-azeotropic refrigerant for RAC systems to ensure compliance with technical procedures and improve system efficiency.

Due to their benefits in interior thermal comfort, energy saving, and noise reduction, radiant cooling systems have received wide attention. Radiant cooling systems can be viewed as a part of buildings’ maintenance structure and a component of cooling systems, depending on their construction. This article reviews studies on heat exchange in rooms utilizing radiant cooling systems, including research on conduction in radiant system structures, system cooling loads, cooling capacity, heat transfer coefficients of cooling surfaces, buildings’ thermal performance, and radiant system control strategy, with the goal of maximizing the benefits of energy conservation. Few studies have examined how radiant cooling systems interact with the indoor environment; instead, earlier research has focused on the thermal performance of radiant cooling systems themselves. Although several investigations have noted variations between the operating dynamics of radiant systems and conventional air conditioning systems, the cause has not yet been identified and quantified. According to heat transfer theory, the authors suggest that additional research on the performance of radiant systems should consider the thermal properties of inactive surfaces and that buildings’ thermal inertia should be used to coordinate radiant system operation.

In this study, the thermodynamic behavior of a combined cycle power plant with integrated solar-driven inlet air cooling was simulated for Tehran, Phoenix, and Houston during warm-hot seasons. A considerable reduction in the output power was realized during hot ambient conditions due to the lower density of the air and lower mass flow rate to the turbines. The output power decreases from 306.6 to 260.8 MW as ambient temperature increases from 15 to 45 °C. This research focuses on utilizing solar cooling systems to achieve low inlet air temperature to generate high-electricity yields. Four different types of solar collectors and two different absorption chiller units were selected and simulated for each city to achieve the required goal. It was identified that integrating a solar inlet air cooling (SIAC) system can avert the reduction in output power with no impact on efficiency. The humid climatic condition in Houston and the low electricity cost in Tehran posed some challenges in designing a feasible SIAC system. However, by optimizing the solar collectors and cooling capacities, an optimal solution for utilizing inlet air cooling in humid climates is presented. In terms of overall impact, the evacuated flat plate collector (EFPC) coupled with a double-effect absorption chiller displayed the best economic performance among the four variants under study. In Phoenix, this combination can maintain output power during hot days with a DPR of 2.96 years.

Purpose Agricultural production is facing multiple challenges from global warming. Nitrogen (N) plays an essential role in high-temperature tolerance and crop yield, which may depend on leaf cooling capacity. However, the effects of nitrogen on the leaf temperature response and the regulatory mechanisms of leaf cooling capacity under increased environmental temperature are largely unknown. Methods Currently, we evaluated the effects of nitrogen on the dynamic change in leaf temperature and the balance between heat dissipation and absorption, which contributes to leaf cooling capacity. Results The results showed that cucumber plant growth and transpiration rate significantly increased with N supply, while leaf temperature decreased. As the environmental temperature increased, the cucumber leaf temperature and leaf cooling capacity increased, and the leaf cooling capacity improved with the N supply. Leaf temperature was negatively correlated with transpiration rate, and the increased transpiration rate contributed to higher heat dissipation and leaf cooling capacity under a high nitrogen supply. Leaf water content and water potential increased with N supply, which resulted in higher leaf specific heat capacity and heat absorption. However, nitrogen-deficient plants increased the nonstructural carbon content (NSC), structural carbon content (SC), and NSC/SC ratio, thus increasing plant adaptation to environmental stresses. Conclusions Nitrogen supply improved leaf cooling capacity by increasing the leaf transpiration rate and specific heat capacity, thereby regulating the balance between heat dissipation and absorption. Improving leaf cooling capacity by N supply may be a new strategy to increase plant adaptation to increased environmental temperatures.

This study investigated cooling capacity concerns in 2-pipe economy fan coil units used in Korea, prompted by frequent field replacement claims and HVAC design engineer feedback. Comprehensive field testing of approximately 100 economy FCUs revealed significant performance discrepancies. KS B 6377 certified models (n=49) performed 6.9% below ratings, while uncertified models (n=54) averaged 9.0% below rated airflow specifications. Detailed in-situ evaluation of selected models showed uncertified units achieving only 68% of rated airflow at maximum fan speed, whereas certified models delivered 138% of rated airflow. Laboratory testing of certified models revealed internal inconsistencies, with cooling capacity ranging from 85.4% to 118.2% of rated capacity as a result of varying airflow rates despite meeting NC-40 acoustic criteria. Reduced cooling capacity results from intentionally diminished airflow rates used for noise mitigation—a concerning compromise of thermal comfort for acoustic compliance. Recommendations include implementing advanced low-noise fan technologies and specifying precise fan flowrate conditions in KS B 6377 certification standards.

Indirect evaporative coolers (IECs) use the latent heat of water evaporation to cool air. This system has the advantage of operating at low power without a compressor and does not increase the absolute humidity of the air. However, an IEC is difficult to use on its own because its cooling capacity is limited by the theoretical constraint of the wet-bulb temperature of the ambient air. Therefore, an air conditioning unit (ACU) was integrated with an IEC and experimentally evaluated in this study. The dry and wet channels of the IEC were integrated with an ACU evaporator and a condenser, unlike previous studies where IECs were integrated solely with either an evaporator or a condenser. This reduced the cooling load on the evaporator and helped the condenser to dissipate heat to improve the performance of the existing ACU. In addition, the IEC was equipped with baffles to improve its performance. To assess the extent of the performance improvement due to integration with the IEC, comparisons were also performed under the same experimental conditions with an ACU only. The results showed that under conditions with an indoor temperature of 32 °C, integrating the IEC with the ACU increased the average cooling capacity by 13.1% and decreased the average power consumption by 8.60% during the test period, compared to using only the ACU. Consequently, the average coefficient of performance (COP) increased by 19.5% compared to using only the ACU under the same conditions.