scholarly journals A Novel Design and Performance Evaluation Technique for a Spool-Actuated Pressure-Reducing Valve

Actuators ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 232
Author(s):  
Haroon Ahmad Khan ◽  
So-Nam Yun ◽  
Eun-A Jeong ◽  
Jeong-Woo Park ◽  
Byung-Il Choi

Solenoid-actuated pressure-reducing valves are commonly used in hydraulic machinery. Most studies on solenoid-actuated pressure control devices are focused on the electrical input signals or on the control techniques for the solenoid valves, but no study has been done that determines the influence of the design parameters on the valve’s output. Before designing a controller, it is imperative to know the valve’s performance by determining the significance of each valve parameter. In this study, established physical laws from fluid dynamics and mechanics are used to build a model that is solved using the ODE 45 solver of Simulink in the time domain. The actuating force, up to 15 N, exerted on the spool and the inlet pressure, ranging from 50 to 80 bar, are obtained through experimentation. It is found that the output pressure fluctuates significantly if the outlet is blocked, while at the fully opened outlet condition, a flow rate of 12 (L/min) was obtained. A pin diameter of 2.15 mm enables us to vary the output pressure between 0 and 41 bar. We found that higher inlet pressure leads to lower output pressure as the outlet is opened. No linearization of the actual mathematical model is performed, which makes the study unique.

2021 ◽  
Vol 13 (7) ◽  
pp. 168781402110343
Author(s):  
Mei Yang ◽  
Yimin Xia ◽  
Lianhui Jia ◽  
Dujuan Wang ◽  
Zhiyong Ji

Modular design, Axiomatic design (AD) and Theory of inventive problem solving (TRIZ) have been increasingly popularized in concept design of modern mechanical product. Each method has their own advantages and drawbacks. The benefit of modular design is reducing the product design period, and AD has the capability of problem analysis, while TRIZ’s expertise is innovative idea generation. According to the complementarity of these three approaches, an innovative and systematic methodology is proposed to design big complex mechanical system. Firstly, the module partition is executed based on scenario decomposition. Then, the behavior attributes of modules are listed to find the design contradiction, including motion form, spatial constraints, and performance requirements. TRIZ tools are employed to deal with the contradictions between behavior attributes. The decomposition and mapping of functional requirements and design parameters are carried out to construct the structural hierarchy of each module. Then, modules are integrated considering the connections between each other. Finally, the operation steps in application scenario are designed in temporal and spatial dimensions. Design of cutter changing robot for shield tunneling machine is taken as an example to validate the feasibility and effectiveness of the proposed method.


Author(s):  
Matthias Balázs ◽  
Martin Spieck

Abstract The DLR Planetary Roller Spindle Drive (PRSD), a new linear actuator developed at the German Aerospace Center (DLR), transforms fast rotation of a drive into slow but powerful linear movement. To optimize dynamical behaviour and performance of modified PRSD design versions, modelling and calculation methods have been developed, taking into account the very special requirements of this new design. To analyze the operating characteristics and performance figures, the DLR Planetary Roller Spindle Drive was modelled as a multibody system (MBS). Special attention was directed on the description of the complex contact mechanics between the PRSD elements. Accompanying experiments ensured the accuracy of the modelling. Analysis of the MBS model of an existing PRSD in the time domain showed satisfying accordance with testbench measurements.


Author(s):  
Khaled A. Galal ◽  
Ghassan R. Chehab

One of the Indiana Department of Transportation's (INDOT's) strategic goals is to improve its pavement design procedures. This goal can be accomplished by fully implementing the 2002 mechanistic–empirical (M-E) pavement design guide (M-E PDG) once it is approved by AASHTO. The release of the M-E PDG software has provided a unique opportunity for INDOT engineers to evaluate, calibrate, and validate the new M-E design process. A continuously reinforced concrete pavement on I-65 was rubblized and overlaid with a 13–in.-thick hot-mix asphalt overlay in 1994. The availability of the structural design, material properties, and climatic and traffic conditions, in addition to the availability of performance data, provided a unique opportunity for comparing the predicted performance of this section using the M-E procedure with the in situ performance; calibration efforts were conducted subsequently. The 1993 design of this pavement section was compared with the 2002 M-E design, and performance was predicted with the same design inputs. In addition, design levels and inputs were varied to achieve the following: ( a) assess the functionality of the M-E PDG software and the feasibility of applying M-E design concepts for structural pavement design of Indiana roadways, ( b) determine the sensitivity of the design parameters and the input levels most critical to the M-E PDG predicted distresses and their impact on the implementation strategy that would be recommended to INDOT, and ( c) evaluate the rubblization technique that was implemented on the I-65 pavement section.


Author(s):  
Lei Yu ◽  
William T. Cousins ◽  
Feng Shen ◽  
Georgi Kalitzin ◽  
Vishnu Sishtla ◽  
...  

In this effort, 3D CFD simulations are carried out for real gas flow in a refrigeration centrifugal compressor. Both commercial and the in-house CFD codes are used for steady and unsteady simulations, respectively. The impact on the compressor performance with various volute designs and diffuser modifications are investigated with steady simulations and the analysis is focused on both the diffuser and the volute loss, in addition to the flow distortion at impeller exit. The influence of the tongue, scroll diffusion ratio, diffuser length, and cross sectional area distribution is examined to determine the impact on size and performance. The comparisons of total pressure loss, static pressure recovery, through flow velocity, and the secondary flow patterns for different volute designs show that the performance of the centrifugal compressor depends upon how well the scroll portion of the volute collects the flow from the impeller and achieves the required pressure rise with minimum flow losses in the overall diffusion process. Finally, the best design is selected based on compressor stage pressure rise and peak efficiency improvement. An unsteady simulation of the full wheel compressor stage was carried out to further examine the interaction of impeller, diffuser and the volute. The unsteady flow interactions are shown to have a major impact on the performance of the centrifugal stage.


Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2163 ◽  
Author(s):  
Sanghyun Yoon ◽  
Jinhwan Kim ◽  
Kyung-Ho Cho ◽  
Young-Ho Ko ◽  
Sang-Kwon Lee ◽  
...  

In this study, inertial mass-based piezoelectric energy generators with and without a spring were designed and tested. This energy harvesting system is based on the shock absorber, which is widely used to protect humans or products from mechanical shock. Mechanical shock energies, which were applied to the energy absorber, were converted into electrical energies. To design the energy harvester, an inertial mass was introduced to focus the energy generating position. In addition, a spring was designed and tested to increase the energy generation time by absorbing the mechanical shock energy and releasing a decreased shock energy over a longer time. Both inertial mass and the spring are the key design parameters for energy harvesters as the piezoelectric materials, Pb(Mg1/3Nb2/3)O3-PbTiO3 piezoelectric ceramics were employed to store and convert the mechanical force into electric energy. In this research, we will discuss the design and performance of the energy generator system based on shock absorbers.


Author(s):  
Yuri I. Biba ◽  
Zheji Liu ◽  
D. Lee Hill

A complete effort to redesign the aerodynamic characteristics of a single-stage pipeline compressor is presented. The components addressed are the impeller, diffuser region, and the volute. The innovation of this effort stems from the simultaneous inclusion of both the noise and aerodynamic performance as primary design parameters. The final detailed flange-to-flange analysis of the new components clearly shows that the operating range is extended and the tonal noise driven by the impeller is reduced. This is accomplished without sacrificing the existing high efficiency of the baseline machine. The body of the design effort uses both Computational Fluid Dynamics (CFD) and vibro-acoustics technology. The predictions are anchored by using the flange-to-flange analysis of the original design and its experimental performance data. By calculating delta corrections and assuming that these deltas are approximately the same for the new design, the expected performance is extrapolated.


2021 ◽  
Vol 7 (1) ◽  
pp. 49-58
Author(s):  
Mohammad Awwad

Background: Water floods have a considerable impact on roads sustainability by creating roads cracks, breaking down and holes, and failure for some other parts. The existence of good drainage system serviced the road and draining the water resulted from rain floods is crucial. These significant influences can be classified as positive or negative, low, moderate, or high. Aim and Objectives: This paper discusses the water floods and rainfall effects on roads and highways in Jordan as well as the drainage system on road sustainability and performance. The main aim of this paper is to investigate and analyse water as rainfall or floods affecting roads and highways in Jordan. The importance of this study is represented by studying and analysing the effects of rainfall and water floods on road construction and sustainability in Jordan after the latest high rain sizes of this winter and water floods, which affect the roads and highways in a good percentage. The other importance of the study is represented in offering solutions to problems caused by the environmental effects, specially floods and high rainfall rates. Methodology: all data and information about status of Jordanian roads during winter and floods are collected from real cases of about 40 main and semi-main roads in Jordan.  Results and Conclusions: A good drainage system and repair operations and maintenance generally have a positive impact on road sustainability and survival age. The effects of slopes of the road and surface of the asphalt, rainfall intensity, and water flow velocity on drainage length and drainage time and water depth are discussed here. Doi: 10.28991/cej-2021-03091636 Full Text: PDF


2018 ◽  
Vol 7 (4) ◽  
pp. 1-27
Author(s):  
Renas K.M. Sherko ◽  
Yusuf Arayici ◽  
Mike Kagioglou

A significant amount of energy is consumed by buildings due to ineffective design decisions with little consideration for energy efficiency. Yet, performance parameters should be considered during the early design phase, which is vital for improved energy performance and lower CO2 emissions. BIM, as a new way of working methodology, can help for performance-based design. However, it is still infancy in architectural practice about how BIM can be used to develop energy efficient design. Thus, the aim is to propose a strategic framework to guide architects about how to do performance-based design considering the local values and energy performance parameters. The research adopts a multi case study approach to gain qualitative and quantitative insights into the building energy performance considering the building design parameters. The outcome is a new design approach and protocol to assist designers to successfully use BIM for design optimization, PV technology use in design, rules-based design and performance assessment scheme reflecting local values.


Sign in / Sign up

Export Citation Format

Share Document