Experimental Testing Of Prototype Research Articles

Numerical modelling of global/local mechanisms and sensitivity analysis for the seismic vulnerability assessment of glass curtain walls

Façades represent complex and vulnerable components for buildings, due to the intrinsic fragility and brittleness of glass, and require specific design and calculation tools, both for ordinary and extreme design loads. In this context, the availability of consolidated and strategic modelling strategies is of utmost importance for structural safety considerations and optimal decisions. In this paper, the attention is focused on the assessment of different modelling strategies for the global and local behaviour analysis of Glass Curtain Walls (GCWs) under in-plane seismic loads. Benefits and limitations are discussed for a more refined (but expensive, “MREF”) and a simplified (and computationally efficient, but weak in capturing local phenomena, “MSIMP”) model assemblies developed in ABAQUS and SAP2000, respectively. Careful consideration is given for typical mechanisms, local responses, key performance indicators for the façade components (i.e., stress and deformation peaks) for a reference GCW under monotonic and cyclic loads, as well as for major effects due to general input parameters (i.e., contact mechanisms, clearance, friction, bare frame features, secondary components, etc.), based on a parametric sensitivity investigation. The parametric comparative results are critically discussed, with the support of an experimental prototype test from literature, and the most influencing parameters are emphasized, to improve and facilitate the development of further design and modelling optimization strategies.

Abstract TP288: Selective Brain Hypothermia Induced by Thermoelectric Cooling

Background: Stroke or Traumatic Brain Injury (TBI) are leading causes of disability and death in the United States. Hypothermia is a known neuronal protectant. Current hypothermia interventions include intravascular, intranasal, and surface brain cooling technologies but these interventions have not been well utilized clinically. Cooling the brain a few degrees below normothermia (T<36°C) has been shown to yield significant neuroprotective effects. Noninvasive surface cooling methods are most desirable given their less patient complications, provided the desired therapeutic hypothermia effect (T 33-36°C) can be maintained. Method: These investigators propose a novel noninvasive solid state technology that employs addressable Peltier thermoelectric cooling elements to generate hypothermia. ThermoPelt’s closed-looped microcontroller design provides the ability to address individual Peltier elements to selectively reduce the temperature of localized regions of the brain, thus allowing precision therapeutic hypothermic conditions to be realized. Results: Assessment of ThermoPelt performance was accomplished with use of virtual prototype (engineering mathematical model representations of the brain) and early, in vitro experimental physical prototype testing. Preliminary results obtained from virtual and physical prototype tests verify ThermoPelt feasibility to achieve hypothermic conditions. Conclusion: In this new method of generating hypothermia, the preliminary findings demonstrate that our noninvasive ThermoPelt technology is capable of reducing brain temperature at controlled rates to selectively target specific head and neck regions.

A Compact Three-Dimensional Two-Layer Flexible Hinge

The paper proposes a new three-dimensional flexible hinge formed of several serially linked straight- and circular-axis segments that are disposed of in two layers. The novel hinge configuration is capable of large displacements and can be implemented in precision-compliant mechanisms that need to cover large spatial workspaces. Based on simplified geometry, an analytical compliance model is formulated that connects the loads to the displacements at one end of the hinge. Finite element simulation and experimental prototype testing of actual-geometry hinge configurations confirm the analytical model predictions. A related compliance-based analytical model evaluates the maximum loads that can be applied to the hinge and the resulting displacements. The two small-deformation analytical models are subsequently utilized to investigate the relationship between geometric parameters and the hinge performance qualifiers.

A Novel Electric Vehicle Battery Management System Using an Artificial Neural Network-Based Adaptive Droop Control Theory

The novelty of this research lies in the development of a new battery management system (BMS) for electric vehicles, which utilizes an artificial neural network (ANN) and fuzzy logic-based adaptive droop control theory. This innovative approach offers several advantages over traditional BMS systems, such as decentralized control architecture, communication-free capability, and improved reliability. The proposed BMS control system incorporates an adaptive virtual admittance, which adjusts the value of the virtual admittance based on the current state of charge (SOC) of each battery cell. This allows the connected battery cells to share the load evenly during charging and discharging, which improves the overall performance and efficiency of the electric vehicle. The effectiveness of the proposed control structure was verified through simulation and experimental prototype testing with three linked battery cells. The small signal model testing demonstrated the stability of the control, while the experimental results confirmed the system’s ability to evenly distribute the load among battery cells during charging and discharging. We introduce a unique battery management system (BMS) for electric cars in this paper. Our suggested BMS was implemented and tested satisfactorily on a 100 kWh lithium-ion battery pack. When compared to typical BMS systems, the results show a surprising 15% increase in overall energy efficiency. Furthermore, the adaptive virtual admission function resulted in a 20% boost in battery life. These large gains in energy efficiency and battery longevity demonstrate our BMS’s efficacy and superiority over competing systems. Overall, the proposed BMS represents a significant innovation in the field of electric vehicle battery management. This combination of ANN and adaptive droop control theory based on fuzzy logic provides a highly efficient, reliable, and economical solution for EV battery cell management.

Geothermal Pavements: Experimental Testing, Prototype Testing, and Numerical Analysis of Recycled Demolition Wastes

Geothermal pavements have the potential to reduce the pavement surface temperature by circulating fluid in pipes within the pavement structure. This research investigated an innovative geothermal pavement system with multiple benefits, such as reducing the surface temperature and harvesting heat energy for power generation. This research aimed to provide an understanding of the mechanical properties of geothermal pavements constructed with construction and demolition (C&D) waste materials through large-scale physical testing, experimental testing, small-scale prototype testing, and numerical simulation. The mechanical properties of the geothermal pavement system were assessed under long-term traffic loading conditions using a prototype test system. The repeated load triaxial and repeated-load California bearing ratio tests were also undertaken to evaluate the effect of pipe inclusion on the permanent deformation, stiffness, and strength of the pavement base. A numerical model was subsequently developed and calibrated using the data from small-scale prototype testing. In addition, the effects of the flow rate and pipe materials on the thermal performances of the geothermal pavements were also investigated in this research. The inclusion of pipes in the pavement base layer was found to have negligible detrimental effects on the deformation behavior of RCA. The resilient moduli of recycled concrete aggregate (RCA) samples slightly decreased with the inclusion of pipes. An HDPE pipe reduced the stiffness of the RCA + HDPE mix. On the other hand, a copper pipe’s high stiffness improved the mix’s strength. The numerical simulations indicated that for the HDPE pipe, increasing the flow rate from 500 mL/min to 2000 mL/min reduced the surface temperature by approximately 1.3%, while using the copper pipe resulted in an approximately 4% further decrease in the surface temperature compared to the HDPE pipe.

Demonstrating non-isothermal vacuum membrane air dehumidification for efficient next-generation air conditioning

Vacuum membrane air dehumidification has gained significant interest in recent years as a highly efficient means of air dehumidification. Prior theoretical modeling work by the authors introduced the Active Membrane Energy Exchanger (AMX) concept, which combines active heat exchange and vacuum membrane dehumidification into one non-isothermal system, and found that it could outperform other air conditioning technologies under many conditions. However, no experimental literature exists on combining active heat exchangers and vacuum membrane dehumidification. The goal of the present study is to evaluate the dehumidification (mass transfer) performance of the AMX concept relative to isothermal membrane dehumidification through three main methodologies: (1) membrane material-level characterization, (2) experimental prototype development and testing, and (3) computational fluid dynamics (CFD) simulations. The dense membranes used in this work showed up to a 40% increase in water vapor permeance at cooler temperatures, and the prototype system showed up to a 6% increase in humidity removal when the air was simultaneously cooled. Furthermore, the membrane module-integrated heat exchange tubes provided additional mixing and turbulence, leading to a 4–8% increase in humidity removal. The upper limit coefficient of performance was equal to approximately 2.2, necessitating advanced system designs to improve efficiency. This study is the first to highlight that combining the cooling and vacuum dehumidification processes can improve dehumidification performance.

“PNSVEI” - Model of innovation development in health education

Abstract Issue Health awareness plays an important role in strengthening health potential and determines engagement in health promotion and prevention activities, especially during pandemic. For this reason, an innovative approach to health education is necessary to encourage society to become active in this area. Description of the problem The aim of the presentation is to show a model of innovation development in health education called the “PNSVEI” (Problem, Need, Solution, Validation, Implementation). This model has been developed based on the experiences collected during health educational products development and their implementation during regular educational interventions focused on knowledge improvement regarding healthy lifestyle among Polish school students in the last five years. Results The model consists of two main phases: development and validation of solution in health education. The development step involves defining the problem and need of the target group, and solution prototype development based on the defined need and co-creation process. Validation includes experimental prototype testing in cooperation with different stakeholders, final prototype development, possible intellectual property process, than research evaluation and implementation to the society. Lessons The “PNSVEI” Model shows that the research evaluation and innovation implementation in health education area should be preceded by multi-directional actions and requires the cooperation of researchers with different stakeholders. Intellectual property certificates increase possibility to acquire business sponsorship what may give the chances of raising funds for future evaluations of solutions by researchers. Defining the needs of the target group, their engagement in the co-creation process and experimental prototype testing increase the chances of implementing health educational solutions to the population. Key messages Implementation of innovation in health education should be preceded by multi-directional actions. Need definition of stakeholders increase the chance of implementation in health education.

Performance Optimization of Ejector using Computation Fluid Dynamics

Ejector is a device used for carry low pressure fluids with no mechanical force, high pressure flow. This contains the main nozzle, chamber for suction, chamber for mixing and diffuser.It is used in vaccum pumps, condensers, steam refrigeration, Because of its simple structure, gas mixing, pneumatic transport (no moving parts) and reliable operation. It is also used in pumps for lifting slurries and waste material containing solids from tanks and sumps. Due to their simplicity and high reliability, however, jet ejectors are widely used in industries with low efficiency. The project's goal is to optimize the efficiency of jet ejectors for each operating condition.Consequently, the primary fluid consumption and operating cost is minimized. A commercial computational fluid dynamics tool would be used to analyse the flow characteristics inside the ejector geometry. The results of the CFD simulation could be used to understand the effect of fluid velocity and pressure ratio on the ejector performance. The analysis would also be carried out by varying the primary and secondary nozzle dimensions. Performance of ejectors under various operating conditions is generally obtained through an experimental testing of prototype or scaled ejectors. The availability of performance parameters for such ejectors is limited, and experimental testing can be cost prohibitive.

Modeling Gerotor Pump Performance in Artificial Lift for Single-Phase and Multiphase Conditions

Summary Gerotors are positive displacement pumps and candidates for artificial lift in the oil and gas industry. This study evaluates the performance of a unique gerotor pump design under single-phase and multiphase conditions. The gerotor pump performance is modeled with computational fluid dynamics (CFD) to develop a virtual prototype of the multiphase performance behavior. The gas/liquid flow is modeled using a homogeneous multiphase approach. A prototype 3D model of a 400 series gerotor pump suitable for application in a 5½-in. casing is developed. The pump volume displacement is consistent with that to be used in subsequent laboratory experimental tests and field prototype testing. Transient 3D CFD is used to simulate the gerotor pump performance under single-phase and multiphase flow conditions. The complex gerotor motion is modeled in CFD using a dynamic meshing technique. Pump rotor speeds applicable to the range of testing conditions were applied. The gas and liquid phase properties correspond to mineral oil and air at the prototype test conditions. The results of the gerotor pump performance are presented for single-phase and multiphase conditions over a range of gas volume fractions (GVFs) from 0 to 0.75. The CFD results show that the flow rate decreases approximately linearly with pump differential pressure, which is typical of positive displacement pumps. Pump performance and efficiency curves are developed relating the pump differential pressure and flow rate. The CFD model methodology is presented with consideration to appropriate selection of the numerical methods, multiphase model, mesh design, dynamic mesh motion, and other aspects to improve the reliability of the numerical simulations. For the same differential pressure, increasing the GVF decreases the gerotor total pumping volume rates. The results establish a first baseline for the pumping system for subsequent comparison with physical model testing to ascertain gas/liquid handling capability of the pump for further optimization for field application. This study evaluates and highlights the potential applicability of gerotors as an alternative artificial lift technology for multiphase pumping. This technology with further development in addition to its inherent mechanical simplicity and compactness can serve as a promising candidate for surface and downhole multiphase pressure boosting for production in the oil and gas industry.

Simulation and Analysis of Variable Antenna Designs for Effective Stroke Detection

The variety of applications of patch antenna for portable applications has opened the avenues for the possibilities of having compact, cost-efficient, and life-saving devices. Considering the challenges of portability and cost in making it feasible for detecting strokes in the masses of developing countries where the demand is quite high, this study builds the groundwork for such device fabrication. In total five antenna designs were investigated for their assessment in identifying the stroke. Two main studies of electromagnetic wave interaction and bio-heating of the human head phantom had been accomplished and the results are compared. The main comparison and identification of the stroke location with the human head phantom are presented by the specific absorption rate (SAR), both visualized as volumetric plot and stacked contour slices for clarifying the shape and positioning of the stroke in vertical and horizontal dimensions. The results show that the SAR values for Antenna A & D are the lowest with the values of 1.44 x 10-5 W/kg and 1.96 x 10-5 W/kg, respectively. But the induced electric field and isothermal temperature achieved were highest by Antenna D, with values of 0.25 emw and 133.92 x 10-8 K, respectively; and, the 2-D far-field radiation patterns confirmed better performance by it amongst all others. Hence, making the Antenna D as the most preferred choice for the prototyping stage. The overall trade-off of key parameters is studied herein in this simulation study and based on that the most suitable antenna design is proposed for the experimental prototype testing. The results suggest that the simulation results give a clear insight into the feasibility of stroke detection with the proposed setup and presents high viability for portable, low-cost, and rapid stroke detection applications.

Optimal Design of TEFC Induction Machine and Experimental Prototype Testing for City Battery Electric Vehicle

This article presents the optimal design and experimental prototype testing of a low-cost motor applied for a city battery electric vehicle, zero emission A-segment. Respecting the car performance specifications, the aluminum cage rotor induction machine is designed to reduce motor cost using totally enclosed fan-cooled technology and a commercial speed encoder of internal combustion engine. An optimization approach and finite elements analysis validation are coupled with thermal calculations and used to size the thermo-electromagnetic parts of the machine. The prototype is manufactured with full instrumentation. During the experiments, an indirect flux-oriented control model is built based on simulations in MATLAB/Simulink environment. Using this real time control platform, the motor control is calibrated on the prototype in test-bench, to ensure the optimum energy consumption and the current and speed regulations in the entire large operating range. Finally, the experimental prototype testing results are shared to show the ideal design solution in term of peak performances, efficiency, thermal and noise, vibration, and harshness behaviors.

Solid-State Bipolar Pulsed-Power Modulator Based on a Half-Bridge Power Cell Structure

This paper addresses the design of a solid-state bipolar pulsed-power modulator based on a series of stacked power cells that realize a simple and robust structure. Each cell is charged in parallel by an LCC resonant converter independently of the discharging loop. A passive cell-balancing design is implemented. The power cell using insulated gate bipolar transistors (IGBTs) can operate in bypass mode without an additional component, and the circuit operation was analyzed. A simple gate driving method, which provides synchronized gate signals without an extra power source of each gate driver using two control loops and isolation transformers, is implemented for the proposed bipolar pulsed-power modulator based on stacked cells. Moreover, an unexpected gate turn-on problem was solved by an additional off signal. To validate the proposed structure and the gate driving scheme, a three-cell, 1.2-kV, 110-A, 1.5- to 4- $\mu \text{s}$ , 3-kHz laboratory experimental prototype test was conducted. The results proved the reliability of the proposed solid-state bipolar pulsed-power modulator.

On the Measurement and Modeling of the Heat Transfer Coefficient of a Hollow-Shaft Rotary Cooling System for a Traction Motor

This paper addresses the heat transfer coefficient (HTC) associated with the hollow-shaft rotor cooling of a traction motor. In such a hollow-shaft cooling system, the coolant is made to flow through the shaft hole in order to cool the rotor. The HTC is estimated using computational fluid dynamics (CFD), where the effect of rotational velocity as well as the coolant flow rate has been accounted for. Experiments are then used to validate the accuracy of CFD models with the assistance of an analytical lumped-parameter thermal network approach. On the basis of CFD simulations and the experimental prototype testing, it is concluded that the rotational speed can significantly increase the convective heat transfer of the shaft hole about 3.8 times at 4500 r/min above the level of the stationary condition. As a result of such analysis, a new dimensionless correlation of the Nusselt number with the Reynolds number is derived.

An Adaptive Carrier Frequency Optimization Method for Harmonic Energy Unbalance Minimization in a Cascaded H-Bridge-Based Active Power Filter

Cascaded H-bridge (CHB) based active power filters (APF) can compensate high-order harmonics in medium and high-voltage systems with relatively low switching frequency. This paper reveals that a severe dc capacitor energy unbalance can be induced by harmonic energy exchange if the frequency of APF output current coincides with the switching harmonic frequency of CHB cells. The mechanism of harmonic energy exchange is analyzed, and it is found that the dc capacitor energy unbalance is essentially affected by the carrier frequency of CHB. A noninteger ratio carrier frequency can be adopted to avoid the divergence of dc voltage, but there is still a significant low-frequency ripple on the dc voltage. This paper proposes an adaptive carrier frequency optimization method. By predicting the dc voltage ripple amplitude under different carrier frequencies, this method can adaptively select the optimal carrier frequency to minimize the dc voltage ripple. The proposed method is also proved to be robust against system parameter variations, and it can be implemented by a practical and simple linear computation method. Results obtained from simulation, experimental prototype, and field test are finally presented to verify the proposed adaptive carrier frequency optimization method.

Hydrodynamic loadings on a horizontal axis tidal turbine prototype

Until recently tidal stream turbine design has been carried out mainly by experimental prototype testing aiming at maximum turbine efficiency. The harsh and highly turbulent environments in which tidal stream turbines operate in poses a design challenge mainly with regards to survivability of the turbine owing to the fact that tidal turbines are exposed to significant intermittent hydrodynamic loads. Credible numerical models can be used as a complement to experiments during the design process of tidal stream turbines. They can provide insights into the hydrodynamics, predict tidal turbine performance and clarify their fluid–structure interaction as well as quantify the hydrodynamic loadings on the rotor. The latter can lead to design enhancements aiming at increased robustness and survivability of the turbine. Physical experiments and complementary large-eddy simulations of flow around a horizontal axis tidal turbine rotor are presented. The goal is to provide details of the hydrodynamics around the rotor, the performance of the turbine and acting hydrodynamic forces on the rotor blades. The simulation results are first compared with the experimental and good agreement between measured and simulated coefficients of power are obtained. Acting bending and torsional moment coefficients on the blade-hub junction are computed for idealised flow conditions. Finally, realistic environmental turbulence is added to the inflow and its impact on the turbine’s performance, hydrodynamics and rotor loadings is quantified.

Study on a high-performance solar thermoelectric system for combined heat and power

In this paper, a high-performance solar thermoelectric system for combined heat and power is developed and investigated. This new system has achieved a higher performance by considering some of the features, including a simplified structure, lower contact thermal resistance, lower convection heat loss, and better heat transfer performance. The mathematical model was built and analyzed. And the models are verified via the experimental prototype test. In addition, the performance of the system under different environmental conditions and operating parameters are evaluated and predicted. The results show that the proposed system can be used for cogeneration of heat water and electric power. And when the solar irradiation is larger than 700W/m2, and water temperature of 13°C, the maximum instantaneous electrical power output was found to be 0.659W at the load resistance 4.2Ω, and the power generation efficiency of the thermoelectric generator (TEG) is 1.956%, which is close to that of a low temperature organic Rankine cycle system. These results indicate the feasibility of the proposed high-performance solar thermoelectric system and give hints for future improvement of the solar thermoelectric system for combined heat and power.

Compliant constant-force linear-motion mechanism

A fully compliant constant-force mechanism that uses an initially angled parallel-guiding mechanism is proposed. A pseudo-rigid-body model (PRBM) of the mechanism is developed and validated using both finite element models and experimental prototype testing. The PRBM is used as a preliminary design tool to identify parameters that result in a constant-force mechanism. An adjustable version of the mechanism is also proposed and is used to assess the range of validity of the PRBM and highlights how the system response can be varied by changing the flexible beams inclination. A finite element based optimization is used to create a modified version of the mechanism that incorporates beam-end rotation effects and offers greater performance. Potential applications for the mechanism are discussed and it is demonstrated as a component of a statically balanced system.

Study on the Plastic Bottle Recycling Based on Evolution Tree for Technical System

Technical system theory of evolution tree was used in the study of the plastic bottle recycling, and established the evolutionary line of plastic bottle recycling on the basis of the analysis of plastic bottle recycling recovery evolution tree, and summed up a new smart plastic bottle recycling program. The new recovery recovers and smashes the plastic bottles through technical system, and communicates with users through automatically reward system and rewards the latter. The experimental prototype test results show: post treated fragments of plastic bottles are small, which are convenient to transport and take advantage of; the operation of recovery is easy, and the interface of man-machine interaction is friendly which is easy to expand functions.

Innovative Design of Plastic Bottle Recycling Box Based on ARM

Aiming at the problems of on-site plastic bottles recycling and the reuse of waste, the automatic recycling system was developed on the basis of ARM. As the main controller, ARM not only controls the mechanical system of the collector to recover and break plastic bottles, but also communicates with and rewards the user by the automatic reward system through the wireless network. The experimental prototype test results show: post treated fragments of plastic bottles are small, which are convenient to transport and take advantage of; the operation of recovery is easy, and the interface of man-machine interaction is friendly which is easy to expand functions.

Incorporating dust lift-off into a CFD model of a blast furnace gravity dust-catcher

A gravity dust-catcher separates a mixture of dusts from the spent top gas flow of a blast furnace. These dusts are predominantly made up of limestone, iron ore and coke/coal. As a result of the turbulent gas flow patterns within a dust-catcher, modelling of the flow pattern can be very complex, attributed to the turbulent vortices that can be formed within the main body of the structure. Using data from an experimental prototype test rig, a simple model to capture the lift-off characteristics of particle lift-off from dust pile surfaces is created and incorporated into a computational fluid dynamics (CFD) model of the dust-catcher.The variation of particle separation performance over a typical blast furnace (BF) operational cycle is analysed. An attempt is made to explain the observed phenomena in terms of particle–fluid interaction. It is found that particle separation efficiency is largely unaffected by dust lift-off at low dust-catcher hopper fullness levels, but is significant at higher levels. It is found that the topography of the dust surface is important when predicting particle lift-off trends. It is concluded that this is due to the exposure experienced by a given particle when subjected to a surface velocity.