This paper proposes the lubrication characteristics of the worn slipper in the slipper–swashplate pair. The mathematical analysis of lubrication characteristics of slipper with…
Abstract
Purpose
This paper proposes the lubrication characteristics of the worn slipper in the slipper–swashplate pair. The mathematical analysis of lubrication characteristics of slipper with the measured surface roughness distribution is introduced. Based on the results from the test rig, it carries out the result compassion in different operating conditions.
Design/methodology/approach
This paper introduces the measured surface roughness distribution of new and used slippers and generates the oil film thickness distribution with it. An average flow Reynolds equation of the pressure distribution is introduced too. The experimental results are carried out on a novel adjustable oil film thickness test rig.
Findings
The surface roughness of the worn slipper enlarges the reacting force and torque only if the oil film thickness is small. When the ratio of oil film thickness to the root mean square of surface roughness is much smaller than 3, the influence of it on torque is obvious.
Originality/value
Different surface roughness of worn slipper proposed in this paper has an influence on the lubrication characteristics. As the slipper is worn after a period of use, the changed lubrication characteristics should be considered in the slipper design.
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The purpose of this paper is to propose an adjustable oil film thickness test rig for detecting lubrication characteristics of the slipper. The mathematical analysis of…
Abstract
Purpose
The purpose of this paper is to propose an adjustable oil film thickness test rig for detecting lubrication characteristics of the slipper. The mathematical analysis of lubrication is introduced. Based on the results from the test rig, the results comparison from test rig and mathematical analysis is carried out.
Design/methodology/approach
This paper introduces a mechanism which can adjust the oil film thickness between the slipper and swash-plate. Feasibility is ensured, and the accuracy of test rig is guaranteed by the three-coordinate measuring machine. Three displacement sensors show the oil film thickness and its shape. The reacting force and torque resulting from oil film can be achieved by three S-type force sensors and a torque sensor, respectively.
Findings
The relative error of the reacting force is small. The relative error reduces and is acceptable when the deformation of retainer is taken into account. The thickness and tilt angle of oil film have less effect on the reacting force. However, they are significantly impact on torque.
Originality/value
The test rig proposed in this paper is able to adjust the oil film thickness, which is used to detecting the lubrication characteristics in pump design.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0166/
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This paper aims to propose the slipper/swash plate pair loaded with a step motor-spring mechanism to reduce the energy consumption under different rotating rate conditions. The…
Abstract
Purpose
This paper aims to propose the slipper/swash plate pair loaded with a step motor-spring mechanism to reduce the energy consumption under different rotating rate conditions. The relationship between the operating conditions, oil film thickness and energy consumption is analyzed. The system dynamic model of the slipper/swash plate pair loaded with a step motor-spring mechanism is introduced. Based on the results of the experiment, the PI controller and step motor-spring mechanism are useful for reducing energy consumption.
Design/methodology/approach
This paper introduces the energy consumption of the slipper/swash plate pair. A system dynamic model of the slipper/swash plate pair loaded with a step motor-spring mechanism is introduced too. In the experiment, three step motor and S-type force sensor are used to control the oil film thickness.
Findings
PI controller and the step motor-spring mechanism are useful for controlling the oil film thickness and reducing the energy consumption under different rotating rate conditions. The accuracy of the oil film thickness control is acceptable and the response time is a bit long
Originality/value
PI controller and the step motor-spring mechanism are useful for controlling the oil film thickness and reducing the energy consumption under different rotating rate conditions. The accuracy of the oil film thickness control is acceptable and the response time is a bit long.
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This paper aims to carry out a thermal-hydraulic simulation model for pump and hydraulic system to predict the temperature increasing and pump performance. Based on the model, how…
Abstract
Purpose
This paper aims to carry out a thermal-hydraulic simulation model for pump and hydraulic system to predict the temperature increasing and pump performance. Based on the model, how to alleviate the temperature is introduced. Besides, the optimization of piston is carried out.
Design/methodology/approach
This paper analyzes the heat generation in lubricating interfaces of the pump with energy conversion theory. The heat transfer inside the pump is analyzed with the control volume method. The simulation model is constructed in AMESim because of its operating friendly nature. The experiment is carried out to prove the validity and accuracy of the simulation model.
Findings
Temperature has less effect on the mechanical loss of pump. However, it has a great impact on volumetric efficiency. To reduce the temperature on the piston surface, the size of the piston should be optimized.
Originality/value
This paper fulfills a novel thermal-hydraulic model to evaluate the temperature of the pump. Based on the model, the performance of the pump is determined and optimization is carried out.
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Hakan F. Oztop, Burak Kiyak and Ishak Gökhan Aksoy
This study aims to focus on understanding how different jet angles and Reynolds numbers influence the phase change materials’ (PCMs) melting process and their capacity to store…
Abstract
Purpose
This study aims to focus on understanding how different jet angles and Reynolds numbers influence the phase change materials’ (PCMs) melting process and their capacity to store energy. This approach is intended to offer novel insights into enhancing thermal energy storage systems, particularly for applications where heat transfer efficiency and energy storage are critical.
Design/methodology/approach
The research involved an experimental and numerical analysis of PCM with a melting temperature range of 22 °C–26°C under various conditions. Three different jet angles (45°, 90° and 135°) and two container angles (45° and 90°) were tested. Additionally, two different Reynolds numbers (2,235 and 4,470) were used to explore the effects of jet outlet velocities on PCM melting behaviour. The study used a circular container and analysed the melting process using the hot air inclined jet impingement (HAIJI) method.
Findings
The obtained results showed that the average temperature for the last time step at Ф = 90° and Re = 4,470 is 6.26% higher for Ф = 135° and 14.23% higher for Ф = 90° compared with the 45° jet angle. It is also observed that the jet angle, especially for Ф = 90°, is a much more important factor in energy storage than the Reynolds number. In other words, the jet angle can be used as a passive control parameter for energy storage.
Originality/value
This study offers a novel perspective on the effective storage of waste heat transferred with air, such as exhaust gases. It provides valuable insights into the role of jet inclination angles and Reynolds numbers in optimizing the melting and energy storage performance of PCMs, which can be crucial for enhancing the efficiency of thermal energy storage systems.
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Anjan Nandi and Nirmalendu Biswas
This study aims to investigate the thermal performance enhancements of phase change materials (PCMs) through the integration of extended fins and CuO nanoparticles under the…
Abstract
Purpose
This study aims to investigate the thermal performance enhancements of phase change materials (PCMs) through the integration of extended fins and CuO nanoparticles under the impact of solar irradiation. The research focuses on improving the melting behavior and thermal efficiency of PCM-based energy storage systems to facilitate the design of more efficient energy storage solutions.
Design/methodology/approach
The analysis is conducted on a top-heated rectangular thermal system filled with pure PCM and nanoparticle-enhanced PCM (NePCM) mixed with 0.01% Wt. CuO nanoparticles, with varying fin configurations considering PCM volume and surface area of fins constraint. The shape of the fin is modified from single to multiple numbers, maintaining the same surface area. The analysis is carried out both experimentally and numerically for the without fin case, and the study is extended numerically (utilizing the finite volume method) considering different sizes and positions of the fins. The study evaluates the impact of nanoparticle inclusion, fin geometry variations and the thermal performance of three different types of PCM (lauric acid, RT-35HC and P-58). Numerical results are validated against the in-house experimental results.
Findings
The study successfully validates the numerical simulations with experimental data, enhancing the credibility of the findings for real-world applications. The addition of 0.01% Wt. CuO nanoparticles to PCM resulted in a 16.36% enhancement in energy storage, as observed experimentally, whereas the numerical simulation showed an 8.55% increase. The inclusion of CuO nanoparticles accelerated the melting process across all fin configurations, with a notable enhancement parameter of 16.51% for the single fin arrangement. The introduction of a single fin structure increased the energy storage rate, but further additions of fins led to diminishing returns, with a maximum energy storage rate of 35.19 J/min achieved with CuO-enhanced PCM in the presence of single fin. The study also highlights RT-35HC as the most effective PCM, offering the highest energy storage and fastest melting speed, making it ideal for rapid thermal response applications.
Research limitations/implications
Future research could explore different types and concentrations of nanoparticles as well as a broader range of fin geometries and materials to further enhance the performance of PCM-based energy storage systems. Long-term experimental validation under real-world conditions would also enhance the applicability and reliability of the findings.
Originality/value
This study provides valuable insights into optimizing thermal energy storage systems by combining nanoparticle enhancement and fin geometry optimization. The results offer practical guidance for improving the efficiency and effectiveness of PCM-based energy storage units in various applications.