Design Methodology and Experimental Results of a Test Facility for Active and Conventional Railway Suspensions

Purpose This study aimed to investigate whether increasing the social presence within an Airbnb lodging environment could nudge guests toward altruistic cleaning behaviors. Design/methodology/approach The study was based around a theoretical framework combining the social-market versus money-market relationship model, nudge theory and social presence theory. A series of three field experiments were conducted, in which social presence was manipulated to test its impact on guest cleaning behaviors prior to departure. Findings The experimental results confirmed the underlying hypothesis that an Airbnb listing’s enhanced social presence can subtly induce guests to help clean their rental units prior to departure. Originality/value This study is the first to examine behavioral nudging in an Airbnb context. It is also one of the first field experiments involving Airbnb. The study findings offer clear theoretical and practical implications.

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Effects of Wind on the Heat Flow of FPSO Topsides Subject to Fire: An Experimental and Numerical Study

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 2 ◽

10.1115/omae2010-20761 ◽

2010 ◽

Author(s):

Joon Young Yoon ◽

Seong Hwan Kim ◽

Gwon Cheol Yu ◽

Jung Kwan Seo ◽

Bong Ju Kim ◽

...

Keyword(s):

Thermal Diffusion ◽

Numerical Study ◽

Wind Tunnel Test ◽

Experimental Results ◽

Test Facility ◽

Test Model ◽

Cfd Simulations ◽

Fire Engineering ◽

Diffusion Characteristics ◽

Fire Loads

The aim of this paper is to examine the effect of wind on the thermal diffusion characteristics of floating production storage and offloading (FSPO) topside models subject to fire. It is motivated by the need to identify the fire loads on FPSO topsides, taking into account the effects of wind speed and direction. The results of an experimental and numerical study undertaken for these purposes are reported here. This paper is part of Phase II of the joint industry project on explosion and fire engineering of FPSOs (EFEF JIP) [1]. An experiment was performed on a 1/14-scale FPSO topside model using a wind tunnel test facility. The locations of the heat source of the fire were varied, as were the speed and direction of the wind, and the temperature distribution was measured. Computational fluid dynamics (CFD) simulations using the ANSYS CFX program were performed on the test model, with the results obtained compared with the experimental results. It is concluded that wind has a significant effect on the thermal diffusion characteristics of the test model and that the CFD simulations are in good agreement with the experimental results. The insights developed in this study will be very useful for the fire engineering of FPSO topsides.

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Design and Testing of a Can Combustor for a Small Gas Turbine Application

ASME 2013 Gas Turbine India Conference ◽

10.1115/gtindia2013-3691 ◽

2013 ◽

Author(s):

K. V. L. Narayana Rao ◽

N. Ravi Kumar ◽

G. Ramesha ◽

M. Devathathan

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Gas Turbines ◽

Pressure Loss ◽

High Energy ◽

Experimental Results ◽

High Mass ◽

Test Facility ◽

Design Requirements

Can type combustors are robust, with ease of design, manufacturing and testing. They are extensively used in industrial gas turbines and aero engines. This paper is mainly based on the work carried out in designing and testing a can type combustion chamber which is operated using JET-A1 fuel. Based on the design requirements, the combustor is designed, fabricated and tested. The experimental results are analysed and compared with the design requirements. The basic dimensions of the combustor, like casing diameter, liner diameter, liner length and liner hole distribution are estimated through a proprietary developed code. An axial flow air swirler with 8 vanes and vane angle of 45 degree is designed to create a re-circulation zone for stabilizing the flame. The Monarch 4.0 GPH fuel nozzle with a cone angle of 80 degree is used. The igniter used is a high energy igniter with ignition energy of 2J and 60 sparks per minute. The combustor is modelled, meshed and analysed using the commercially available ansys-cfx code. The geometry of the combustor is modified iteratively based on the CFD results to meet the design requirements such as pressure loss and pattern factor. The combustor is fabricated using Ni-75 sheet of 1 mm thickness. A small combustor test facility is established. The combustor rig is tested for 50 Hours. The experimental results showed a blow-out phenomenon while the mass flow rate through the combustor is increased beyond a limit. Further through CFD analysis one of the cause for early blow out is identified to be a high mass flow rate through the swirler. The swirler area is partially blocked and many configurations are analysed. The optimum configuration is selected based on the flame position in the primary zone. The change in swirler area is implemented in the test model and further testing is carried out. The experimental results showed that the blow-out limit of the combustor is increased to a good extent. Hence the effect of swirler flow rate on recirculation zone length and flame blow out is also studied and presented. The experimental results showed that the pressure loss and pattern factor are in agreement with the design requirements.

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Experimental Investigation of the Maximum Heat Transport in Triangular Grooves

Journal of Heat Transfer ◽

10.1115/1.2822694 ◽

1996 ◽

Vol 118 (3) ◽

pp. 740-746 ◽

Cited By ~ 67

Author(s):

H. B. Ma ◽

G. P. Peterson

Keyword(s):

Experimental Investigation ◽

Heat Transport ◽

Heat Pipes ◽

Effective Area ◽

Experimental Results ◽

Test Facility ◽

Working Fluid ◽

Maximum Heat ◽

Pressure Losses ◽

Micro Heat Pipes

An experimental investigation was conducted and a test facility constructed to measure the capillary heat transport limit in small triangular grooves, similar to those used in micro heat pipes. Using methanol as the working fluid, the maximum heat transport and unit effective area heat transport were experimentally determined for ten grooved plates with varying groove widths, but identical apex angles. The experimental results indicate that there exists an optimum groove configuration, which maximizes the capillary pumping capacity while minimizing the combined effects of the capillary pumping pressure and the liquid viscous pressure losses. When compared with a previously developed analytical model, the experimental results indicate that the model can be used accurately to predict the heat transport capacity and maximum unit area heat transport when given the physical characteristics of the working fluid and the groove geometry, provided the proper heat flux distribution is known. The results of this investigation will assist in the development of micro heat pipes capable of operating at increased power levels with greater reliability.

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Fabrication and performance evaluation of two multi-layer passive micromixers

Sensor Review ◽

10.1108/sr-04-2017-0054 ◽

2018 ◽

Vol 38 (3) ◽

pp. 321-325 ◽

Cited By ~ 4

Author(s):

Xueye Chen ◽

Jienan Shen ◽

Zengliang Hu

Keyword(s):

Reynolds Number ◽

Performance Evaluation ◽

Design Methodology ◽

Experimental Results ◽

Microfluidic Chips ◽

Mixing Index ◽

Number Range ◽

Content Type ◽

Chaotic Convection ◽

And Performance

PurposeThe purpose of this study is to provide a micromixer for achieving effective mixing of two liquids. The mixing of two liquids is difficult to achieve in microfluidic chips because they cannot form turbulence at small dimensions and velocities.Design/methodology/approachIn this paper, four kinds of passive micromixers based on splitting–recombination and chaotic convection are compared. First, a better E-shape mixing unit based on the previous F-shape mixing unit has been designed. Then, the E-shape mixing units are further combined to form three micromixers (i.e. E-mixer, SESM and FESM).FindingsFinally, the mixing experimental results show that the mixing indexes of E-mixer, SESM and FESM are more than those of F-mixer when the Reynolds number range is from 0.5 to 100. And at Re = 15, the lowest mixing index of E-mixer is 71%, which is the highest of the four micromixers.Originality/valueAt Re = 80, the highest mixing index of F-mixer and E-mixer is 92 and 94 per cent, respectively, and then it begins to decrease. But the mixing index of SESM and FESM remains close to 100 per cent.

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Using fractional order weakening buffer operator to forecast the main indices of online shopping in China

Grey Systems Theory and Application ◽

10.1108/gs-08-2018-0036 ◽

2019 ◽

Vol 9 (1) ◽

pp. 128-140 ◽

Cited By ~ 2

Author(s):

Xiao Hui Gao ◽

Lifeng Wu

Keyword(s):

Fractional Order ◽

High Speed ◽

Design Methodology ◽

Online Shopping ◽

Experimental Results ◽

Order Number ◽

Growth Trend ◽

Content Type ◽

Economic Indices ◽

Expansion Period

Purpose The purpose of this paper is to predict the main economic indices of online shopping in China. Design/methodology/approach A fractional order weakening buffer operator (WBO) for the GM(1,1) model is put forward in order to solve the problem of limited nonlinear data. The order number of WBO can adjust in line with the scenario. Findings The experimental results indicate that the proposed method can consider the scenario and obtain more accurate forecasting results. Originality/value This study found that the slowdown of growth trend after the previous high speed expansion period will continue, and the online shopping sellers should make more efforts to develop potential consumers to increase its turnover.

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Test Results on the ARL 19 Supersonic Blade Cascade

Journal of Turbomachinery ◽

10.1115/1.3262218 ◽

1988 ◽

Vol 110 (4) ◽

pp. 450-455 ◽

Cited By ~ 1

Author(s):

A. Fourmaux ◽

R. Gaillard ◽

G. Losfeld ◽

G. Meauze´

Keyword(s):

Theoretical Analysis ◽

Data Reduction ◽

Experimental Results ◽

Test Facility ◽

Experimental Program ◽

Test Model ◽

Test Results ◽

Blade Cascade

This paper presents the ONERA contribution in a joint experimental program on the aerodynamics of supersonic airfoil cascades. The first part deals with the specific ONERA way of running cascade tests: description of the test facility, the test model, the instrumentation, and data reduction. Then, after a brief theoretical analysis of the ARL 19 cascade, some experimental results are presented and discussed.

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Village-Scale Electrodialysis Desalination: Field Trial Validation

Volume 2B: 43rd Design Automation Conference ◽

10.1115/detc2017-68410 ◽

2017 ◽

Author(s):

Natasha C. Wright ◽

Amos G. Winter

Keyword(s):

Water Quality ◽

Field Trial ◽

Design Methodology ◽

Specific Energy Consumption ◽

Cost Effective ◽

Experimental Results ◽

Water Recovery ◽

Research Facility ◽

High Recovery ◽

Product Water

This paper presents the design and initial testing of a village-scale photovoltaic (PV) powered electrodialysis reversal (EDR) desalination system for rural India. The system was built by the authors and tested at the Brackish Groundwater National Desalination Research Facility in New Mexico. EDR has the potential to be more cost effective than currently installed village-scale reverse osmosis (RO) systems in off-grid locations due to the lower specific energy consumption of EDR versus RO at high recovery ratios. Lower energetic demand leads to lower solar power system costs for off-grid areas. The system tested in this study is designed to validate that energetic, product water quality, and water recovery requirements can be met. An analytical model of the system that accounts for the composition of natural groundwater is presented and compared to initial experimental results. Additionally, results from the USAID Desal Prize are presented showing the system’s performance in regards to recovery ratio and product water quality. This paper presents the design methodology, resulting system parameters, and experimental results for an initial village-scale PV-EDR field trial.

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Reducing torque ripple of BLDC motor by integrating DC-DC converter with three-level neutral-point-clamped inverter

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-02-2015-0066 ◽

2016 ◽

Vol 35 (3) ◽

Cited By ~ 2

Author(s):

Viswanathan V ◽

Jeevananthan S

Keyword(s):

Design Methodology ◽

Torque Ripple ◽

Drive System ◽

Neutral Point ◽

Experimental Results ◽

Switching Frequency ◽

Servo Drive ◽

Circuit Topology ◽

Brushless Dc ◽

Commutation Torque Ripple

Purpose This paper presents a novel circuit topology based on a three-level neutral-point-clamped (NPC) inverter and a super-lift Luo-converter for minimizing torque ripple in a brushless DC motor (BLDCM) drive system. In the BLDCM, the stator winding inductance generates current ripple, distort the rectangular current shape, which produces the torque ripples. In addition, the torque ripple generates vibration, speed ripple and prevents the use of BLDCM in high-precision servo drive systems Design/methodology/approach Torque ripple can be mitigated by using the three-level NPC inverter, which applies half of dc-link voltage across the BLDCM terminals and this reduces the torque ripple during non-commutation period. The commutation torque ripple is reduced by employing the super-lift Luo-converter at the input of the three-level NPC inverter, which lifts the dc-link voltage to the desired value depending upon the BLDCM speed. Simulations and experimental results show that the proposed circuit topology is an attractive option to reduce the torque ripple significantly. Findings Experimental results show that the proposed topology can reduces the torque ripple significantly at higher speed, and operates with lower power losses than the two-level inverter-fed BLDCM drive system at higher switching frequency. Originality/value This paper has proposed a novel topology using a super-lift Luo-converter and a three-level NPC inverter to address the torque ripple issue in BLDCM drive system.

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