Outlet Configurations Research Articles

Outlet Configuration of a Reversed Circular Flow Jet Impingement Photovoltaic Thermal (PVT)

The utilization of the jet impingement technique is a prevalent approach in enhancing the efficiency of photovoltaic thermal (PVT) collector through the augmentation of heat transfer rate. The present work introduces a novel approach known as the reverse circular flow jet impingement (RCFJI) on a PVT collector. The performance analysis of the PVT collector was assessed through the utilization of CFD simulation. The RCFJI was installed to a jet plate which incorporates 36 holes. The holes were positioned at a spacing of 113.4 mm (x-axis) and 126 mm (y-axis). The air outlet channel of the jet plate has been configured into four different configurations: one hole (1h), three holes (3h), four holes (4h) and five holes (5h) to analyze the best outlet configuration leading to the highest energy performance. The simulation evaluation encompassed a range of solar irradiance spanning from 600 W/m<sup>2</sup> to 900 W/m<sup>2</sup>, while the mass flow rates varied from 0.01 kg/s to 0.14 kg/f for each geometrical design. Based on the research, the configuration that records the highest efficiency was 1h. The maximum photovoltaic efficiency recorded was 11.38% at 600 W/m<sup>2</sup> and mass fl ow rate of 0.14 kg/s. While the maximum thermal efficiency was 63.2% at solar irradiance 900 W/m<sup>2</sup> and mass flow rate of 0.14 kg/s.

Performance evaluation of irrigation outlets with physical model study in Indus basin irrigation system of Pakistan.

The efficiency of water distribution at primary, secondary, and tertiary levels in the Indus Basin Irrigation System (IBIS) has historically suffered due to poor design, suboptimal operation, and water scarcity. To address these issues, the system has been designed with ungated irrigation outlets to ensure equitable water allocation at secondary and tertiary levels. This research evaluates the hydraulic performance of three irrigation outlets: adjustable proportional module (APM), adjustable orifice semi-module (AOSM), and open flume (OF) using a physical model study. A distributary channel model with these outlets was constructed at the Centre of Excellence in Water Resources Engineering, where discharge coefficients (Cd) were calibrated and measured under various hydraulic and geometric conditions, including free and submerged flow conditions, and with adjustments to flow depths and outlet settings. The results showed variability in Cd values under free flow and submerged flow conditions with APM and AOSM ranging from 6.07 to 8.20 and 0.56 to 0.74, respectively, and OF between 2.46 and 4.31. Additionally, the behavior of outlet tampering on Cd values was also assessed under three scenarios: tampering with the half wing wall (1st), tampering with the full wing wall (2nd), and lowering the bed level downstream of the outlet (3rd). The increase in Cd values for APM and AOSM was + 10.84% and + 14.49% under 1st scenario, + 17.12% and + 22.36% under 2nd scenario, and + 24.25% and + 26.30% under 3rd scenario, respectively. The results reveal that even minor tampering with outlet structures can lead to significant deviations in performance, highlighting the importance of maintaining stringent control over outlet configurations to ensure equitable and efficient water distribution. There is a critical need for rigorous, site-specific calibration of irrigation outlets to optimize their performance under local conditions and redesigning outlet structures to minimize the impacts of tampering, thereby enhancing the overall sustainability of water use in large-scale irrigation systems. The findings from this study provide essential insights for irrigation engineers and policymakers tasked with upgrading and maintaining irrigation infrastructure. By adopting a more customized approach to outlet design and management, it is possible to significantly improve water use efficiency and achieve more sustainable irrigation practices.

Design and performance evaluation of the snowflake slope composite flow field based on a biomimetic principle

Design and performance evaluation of the snowflake slope composite flow field based on a biomimetic principle

Energy concentration pipe based on passive jet control for enhancing flow induced vibration energy harvesting

Energy concentration pipe based on passive jet control for enhancing flow induced vibration energy harvesting

Innovative coupled cooling strategy for enhanced battery thermal management: Synergistic optimization of jet impingement and immersion cooling

Innovative coupled cooling strategy for enhanced battery thermal management: Synergistic optimization of jet impingement and immersion cooling

An experimental study on the hydrogen utilization in air-cooled proton exchange membrane fuel cell stack with a novel anode outlet design

An experimental study on the hydrogen utilization in air-cooled proton exchange membrane fuel cell stack with a novel anode outlet design

Numerical analyses of water swirls in aquaculture tanks

Water swirls were observed in both model and prototype aquaculture tanks with bottom drains. This phenomenon was seldom replicated in studies of flow fields of water in aquaculture tanks with computational fluid dynamics. A commonality of these studies is that the linear eddy-viscosity turbulence models were employed. This study delves into the water swirls from the aspect of the generation of the turbulence kinetic energy; both the linear and nonlinear eddy-viscosity turbulence models are used, as well as a Reynolds stress turbulence model. A novel identification method is utilized to pinpoint vortex structures. Numerical results affirm the outstanding performance of the Reynolds stress model to estimate the flow fields of water in aquaculture tanks. Both the linear and nonlinear eddy-viscosity models overestimate the kinetic turbulence energy in the stagnation zone of swirls. The overestimation can be restrained by including the effect of the streamline curvature correction (SCC) to the turbulence production term. Even so, the SCC does not help to improve the estimating accuracy between the Reynolds stress tensor and the mean rate-of-strain tensor. While the nonlinear model offers some improvements, the Reynolds stress model provides a more effectvie solution. After that, we calculate the flow fields of water in aquaculture tanks with different inlet–outlet configurations with the Reynolds stress turbulence model. Both the vertical and horizontal scales of water swirls increase with inlet velocities and Froude numbers, where the Froude number is based on the bottom draining velocity and the water depth above the bottom drain. The vertical distributions of the water residence time in aquaculture tanks are shown to improve the design of tanks.

A topology optimization-based-novel design and comprehensive thermal analysis of a cylindrical battery liquid cooling plate

A topology optimization-based-novel design and comprehensive thermal analysis of a cylindrical battery liquid cooling plate

Effects of the outlet contraction ratio on the performance of liquid kerosene/air two-phase rotating detonation combustors

Effects of the outlet contraction ratio on the performance of liquid kerosene/air two-phase rotating detonation combustors

Improving the cooling effect of proton exchange membrane fuel cells by using biomimetic capillary cooling channels based on topology optimization method

Improving the cooling effect of proton exchange membrane fuel cells by using biomimetic capillary cooling channels based on topology optimization method

Analisis Tenaga Pesentakan Jet Aliran Pekeliling Terbalik (PJAPT) Ke Atas Pengumpul Fotovolta Terma Suria (PVT) Modul Dwimuka

Although photovoltaic thermal (PVT) offers ascertain of benefits, it also has its own limitations. The efficiency of PVT is diminished due to heat gain experienced by its photovoltaic module when subjected to solar radiation. Jet impingement has been recognised as a highly successful technique for the purpose of cooling solar modules, particularly in the context of bifacial module applications. An energy analysis of a reversed circular flow jet impingement on a bifacial PVT collector was perform through an indoor experiment utilizing a solar simulator. The jet plate outlet was varied into four different configurations: one hole (1h), three holes (3h), four holes (4h) and five holes (5h) to identify the jet plate outlet configuration that contributes to the best energy efficiency. The experiment was carried out using a constant solar irradiance of 900 W/m2 and mass flow rate between 0.01 kg/s to 0.14 kg/s. The study’s findings indicate that configuration 1h exhibited the best photovoltaic efficiency of 11.09%. Additionally, the highest thermal efficiency recorded was 63.2%. In summary, it can be concluded that configuration 1h exhibits an overall photovoltaic thermal efficiency of 74.28% when subjected to a mass flow rate of 0.14 kg/s. This configuration outperforms other jet plate outlet configuration in terms of energy performance.

The effects of outlet size, shape, and location on spatial temperature distribution reduction via direct jet impinging in power electronics

The effects of outlet size, shape, and location on spatial temperature distribution reduction via direct jet impinging in power electronics

Investigation of the single-phase immersion cold plate amid PAO-4 and Noah@3000A – An experimental approach and its numerical verification

Investigation of the single-phase immersion cold plate amid PAO-4 and Noah@3000A – An experimental approach and its numerical verification

Experimental and numerical investigations on micromixing performance of multi-orifice cross-flow jet mixers

Experimental and numerical investigations on micromixing performance of multi-orifice cross-flow jet mixers

The optimization method based on the coupling of genetic algorithm and ant colony algorithm for the exhaust outlet space arrangement

The exhaust outlet space arrangement is a crucial part to avoid casualties and economic losses in the event of contaminant gas leakage. To handle this problem, this work proposed a novel optimization method based on the coupling of the genetic algorithm (GA) and ant colony algorithm optimization (ACO), and the fitness function used in the optimization method is constructed as an implicit form. In this proposed optimization method, the ACO is used to obtain the implicit fitness function value, while the GA is selected to conduct the space arrangement optimization based on the iteration results transferred from ACO. With the help of this novel methodology, the influence of obstacles in space could be well considered into the space arrangement optimization, which leads to a reliable optimization result of the exhaust outlet configuration. Moreover, to validate the accuracy and efficiency of this coupling method, the optimization results are taken into the computational fluid dynamics numerical model to give a comparison with the conventional configuration. The comparison results indicate that the exhaust outlet arrangement following the optimization results shows a lower gas concentration value during the diffusion process. In addition, based on this optimal exhaust outlet space arrangement, the models with various leakage rates are also investigated and discussed in the numerical work. It is believed that the proposed method could provide an effective measure for the space arrangement optimization and the design of gas leakage protection.

Indoor Thermal Comfort Sector: A Review of Detection and Control Methods for Thermal Environment in Livestock Buildings

The thermal environment is crucial for livestock production. Accurately detecting thermal environmental conditions enables the implementation of appropriate methods to control the thermal environment in livestock buildings. This study reviewed a comprehensive survey of detection and control methods for thermal environments in livestock buildings. The results demonstrated that temperature, humidity, velocity, and radiation are major elements affecting the thermal comfort of animals. For single thermal environmental parameters, the commonly employed detection methods include field experiments, scale models in wind tunnels, computational fluid dynamics (CFD) simulation, and machine learning. Given that thermal comfort for livestock is influenced by multiple environmental parameters, the Effective Temperature (ET) index, which considers varying proportions of different environmental parameters on the thermal comfort of livestock, is a feasible detection method. Environmental control methods include inlet and outlet configuration, water-cooled floors, installation of a deflector and perforated air ducting (PAD) system, sprinkling, etc. Reasonable inlet configuration increased airflow uniformity by more than 10% and decreased ET by more than 9 °C. Proper outlet configuration improved airflow uniformity by 25%. Sprinkling decreased the temperature by 1.1 °C. This study aims to build a comprehensive dataset for the identification of detection and control methods in research of the thermal environment of livestock buildings.

Numerical modelling of ventilation strategies for mitigating cough particles transmission and infection risk in hospital isolation rooms

This study used numerical modelling to analyze air velocity, cough particle distribution and infection risks in an isolation room. It investigated air change rates, inlet/outlet vent positioning and assessed various ventilation rates and outlet configurations for reducing infection risks. Quantitative assessments revealed different particle escape timings. In Case 1, smaller particles (2–4 μm) took 8.2 s to escape, while in Case 2, this time extended to 22.7 s. At 48 ACH, there were significant improvements in removing particles of various sizes, particularly those sized 2–4 μm, 16–24 μm and 40–50 μm, reducing the infection risk. The use of the Wells-Riley model highlighted considerable reductions in infection probabilities with higher ACH. Specifically, infection risks were reduced to 5% in Case 1 and 17% in Case 2, underscoring the marked advantage of Case 1 in reducing infection probabilities, particularly for smaller particles. Furthermore, escalated ACH values consistently correlated with decreased infection probabilities across all particle sizes, highlighting the pivotal role of ventilation rates in mitigating infection risks. The study comprehensively investigated the distribution of air velocity, dynamics of cough particles and infection risk associated with different ventilation strategies in isolation rooms.

Numerical Investigations of the Thermal-Hydraulic Characteristics of Microchannel Heat Sinks Inspired by Leaf Veins

A microchannel heat sink (MCHS) is a potential solution for chip and battery thermal management. The new microchannel structure is beneficial for further improving the thermal-hydraulic performance of MCHSs. Inspired by leaf veins, six new channel structures were designed, and the effects of the channel structures (three parallel structures named PAR I, II, and III and three pinnate structures named PIN I, II, and III), channel depths (0.4, 0.8, and 1.6 mm), and heat fluxes (20, 50, and 80 kW/m2) were investigated via numerical simulation. The cooling medium was water, and the heating area was 40 × 40 mm2. Both PAR II and PIN III exhibit superior overall performance, characterized by the highest Nusselt number and the lowest heating wall temperature. Moreover, PIN III demonstrates the lowest standard deviation in heating wall temperature, while PAR II exhibits the lowest friction factor. The greater the channel depth is, the larger the solid–liquid contact area is, leading to a reduced wall temperature at the interface under identical conditions of inlet Reynolds number and heating wall heat flux. Consequently, an increase in the Nusselt number corresponds to an increase in the friction factor. The maximum value and standard deviation of the heating wall temperature increase with increasing heat flux, while the Nusselt number and friction factor remain unaffected. The overheating near the two right angles of the outlet should be carefully considered for an MCHS with a single inlet–outlet configuration.

Effects of inlet and outlet configurations on the topological optimization design of cooling plates for lithium-ion batteries

Effects of inlet and outlet configurations on the topological optimization design of cooling plates for lithium-ion batteries

Enhancing heat transfer in microchannels: A systematic evaluation of crescent-like fin and wall geometries with secondary flow

Enhancing heat transfer in microchannels: A systematic evaluation of crescent-like fin and wall geometries with secondary flow