Design Of Test Rig Research Articles

In situ investigation of the influence of varying load conditions on tooth deformation and wear of polymer gears

A new method for in situ deformation and wear measurement of polymer gears has been developed at the LKT and validated for polyamide-66 (PA66) gears at constant loading torque and rotational speed. This contribution contains a more comprehensive validation of the newly developed test method by examining polybutylenterephtalate (PBT) gears under varying loading conditions. The deformation test method is based on measuring and analysing the timing differences between the index pulse signals of rotary encoders on the input and output shaft of the test rig. Since the total tooth deformation is a combination of different effects, such as elastic and plastic deformation, thermal expansion and wear, different testing modes with a low and a high torque level are implemented to separate the effects of elastic deformation on the one hand and plastic deformation and wear on the other hand. As a consequence, the new test rig design allows a deeper understanding of the wear and deformation behaviour of polymer steel gear sets over time. This potential is used to analyse the interactions of different loading conditions on the time-dependent deformation of plastic gears. The influence of both, different transmitting torques and rotational speeds is examined.The test method shows good correlation with well-established ex situ measurements for different combinations of rotational speeds and loading torques and thus could be validated. Long-term gear tests under varying rotational speeds and loading torques show increasing wear and deformation at higher speeds and torques confirming the state of the art described in the literature. In addition, the time dependent deformation behaviour at different load conditions due to superposition of wear and plastic deformation could be analysed in detail.

DESIGN OF A DROP IMPACT TEST RIG FOR ACCELEROMETER VALIDATION FOR TURBOCHARGER APPLICATION

Automotive turbochargers increase internal combustion engine power and efficiency in passenger and commercial vehicles. The vibrational characteristics need to be closely monitored during testing as it indicates the state of the turbocharger and its components. For this purpose, an accurate accelerometer is a must. This paper presents the design of a drop impact test rig for accelerometer validation. The design is based on ASTM E1876 standard and able to cover a frequency range of 0-6000 Hz. This represents a typical turbocharger operating speed of up to 120,000 rpm, with four common types of vibrational mode expected – synchronous, sub-synchronous, harmonic, and non-synchronous. Three materials have been selected for the specimen plate, namely ABS, Copper and AISI 1050 steel. The abovementioned frequency range can be satisfied by varying the specimen thickness. The drop impact test rig allows four different drop heights. Further combined with four different steel ball sizes, the magnitude of induced acceleration can be manipulated during the drop test. This drop impact test rig enables on-site accelerometer validation before any turbocharger gas stands testing, which is crucial for an accurate vibrational measurement.

Design and Prototyping of a Simple Test Rig for Fuel Cock Assy

This work focuses on the design, manufacturing, and testing of a simple test rig for fuel cock assy. The test rig is needed to facilitate the testing of the fuel cock assy prototype that has been reverse-engineered before the component is directly applied and used in motorcycles. Several design concepts of test rigs are proposed and evaluated. The main parts of the test rig are the fuel hose, valve, T-connector, vacuum pressure gage, and hand-suction pump. Upon completion of the assembling process, a series of testing is conducted to see the performance of the test rig. The result indicates that the test rig is working well despite its simplicity. In addition, there is still room for improvement, among others, is the design of supporting stand to gain a better aesthetic value. As for future work, the prototype has ample opportunity to be upgraded into a sophisticated test rig by adding sensors and microcontrollers to allow automatic testing.

Development of a rotor test rig with a novel controllable preload foil-air bearing

The introduction of a lobed clearance profile into a foil-air bearing can improve rotordynamic performance through the delay of the onset of instability speed and consequent suppression of sub-synchronous vibrations. This can be achieved by shimming (preloading) the foil at three angular locations along its interface with the sleeve. This paper presents the design, manufacture and testing of a rotor test rig with a novel controllable preload foil-air bearing design. The design's motorised micrometer screw assemblies securely prescribe a given preload in real time, eliminating the introduction of potential problems associated with the structural compliance of piezoelectric preloading mechanisms. The shaft of a previous test rig is redesigned to achieve a significantly higher speed with the same motor. The design work is guided by simulations. Experiments confirm that the projected preload is sufficient to virtually eliminate sub-synchronous vibration over the operating speed range. The experiments also confirm that the top speed could be significantly increased by redesigning the shaft for a higher bending critical speed. Although preload increases the friction torque, this is mitigated through the application of diamond-like carbon to the journal, and can be further mitigated by applying preload only in regimes of sub-synchronous vibration activity.

Проектирование стенд-макета для исследования внутрикорпусных движителей подводных объектов

Object and purpose of research. This research was intended to design and manufacture a dummy test rig for self-propulsion testing of various in-hull propulsors. This test rig will be used to test waterjet designs for underwater objects. Materials and methods. Analytical assessments on geometry of propeller and stator blades, numerical simulation of operational condition for two-row blade system operating in the water duct as per in-house KSRC techniques. Main results. Interaction of internal waterjets with the hull of underwater object has never been studied before. To estimate this interaction, it was decided to perform self-propulsion tests with a suitable hull model. This work included design and manufacturing of a dummy test rig representing a hull of underwater object and enabling hydrodynamic measurements for an in-hull waterjet. Another result of this work was design and manufacturing of a four-row in-hull propulsion unit. Conclusion. The dummy test rig manufactured in this work could be further used to optimize in-hull waterjets of various configurations. Apart from the configuration described in this paper, it could also be feasible to design, manufacture and apply a combined rim-driven propulsion motor in the initial part of the water duct.

Design of an Innovative Test Rig for Industrial Bearing Monitoring with Self-Balancing Layout

The remote prognosis and diagnosis of bearings can prevent industrial system failures, but the availability of realistic experimental data, being as close as possible to those detected in industrial applications, is essential to validate the monitoring algorithms. In this paper, an innovative bearing test rig architecture is presented, based on the novel concept of “self-contained box”. The monitoring activity is applicable to a set of four middle-sized bearings simultaneously, while undergoing the independent application of radial and axial loads in order to simulate the behavior of the real industrial machinery. The impact of actions on the platform and supports is mitigated by the so-called “self-contained box” layout, leading to self-balancing of actions within the rotor system. Moreover, the high modularity of this innovative layout allows installing various sized bearings, just changing mechanical adapters. This leads to a reduction of cost as well as of system down-time required to change bearings. The test rig is equipped with suitable instrumentation to develop effective procedures and tools for in- and out-monitoring of the system. An initial characterization of the healthy system is presented.

Design and Development of a Twin Disc Test Rig for the Study of Squeal Noise from the Wheel – Rail Interface

Design and Development of a Twin Disc Test Rig for the Study of Squeal Noise from the Wheel – Rail Interface

A Novel Reciprocating Tribometer for Friction and Wear Measurements with High Contact Pressure and Large Area Contact Configurations

There are many moving machine assemblies with conformal tribological contacts at very high contact pressures, e.g., sliding bearings, propeller shaft bearings and machine guideways. Furthermore, applications such as trunnion and guide vane bearing in Kaplan turbines have very low sliding speeds and oscillatory types of motion. Although there is a vast selection of tribology test rigs available, there is still a lack of test equipment to perform friction and wear tests under high contact pressure, reciprocatory sliding and large area contact. The aim of this work is thus to develop a novel reciprocating tribometer and test method that enables friction and wear tests under low-speed reciprocatory sliding with contact pressures up to 90 MPa in a flat-on-flat contact configuration. First, a thorough description of the test rig design is given. Secondly, the influence of contact pressure and stroke length on the tribological properties of a stainless steel and polymer composite material combination is studied. The significance of considering creep, friction during the stroke and contact temperature is specifically highlighted. The novel tribometer can be used to screen different bearing and shaft material combinations and to evaluate the friction and wear performance of self-lubricating bearings for the specific operating conditions found in Kaplan turbines.

A Novel Test Rig Using Air for Investigation of Vibration and Interaction of Two Steam Turbine Control Valves

Abstract The governing of steam turbines is often realized by a set of two or more valves, which control the amount of steam entering the turbine. During part-load operation forces caused by pressure fluctuations and turbulence are acting on the throttling valve and lead to spindle vibrations. Besides these mechanisms, it is assumed that there is also an interaction between the control valves, which leads to another source of vibration. In this paper, the design of a new test rig using air with two parallel control valves is presented. One aspect of the design is the chosen scaling method, which includes a material selection for the valve spindle, and ensures comparability and transferability of the vibrational behavior to the full scale with steam. Another aspect is the selection of measurement equipment. The results show that the reasons for valve vibrations can be located both upstream and downstream of the valve seat. Forces caused by pressure fluctuations in and behind the valve gap lead to similar oscillations at both valves. In addition, the upstream valve causes disturbances that lead to partly differing behavior of the second valve.

(Invited) Design and Testing of a High-Pressure PEM Water Electrolyzer System Test Rig

Renewable energy-based hydrogen production via low temperature water electrolysis is attracting increased interest globally. Proton exchange membrane water electrolysis (PEMWE) offer several benefits over the more mature alkaline water electrolysis technology. The PEMWE-technology is particularly suitable for balancing variable power due to its great load-following capability. The PEMWE-technology can also be designed to operate at high current densities and pressures, which can reduce the system footprint and make the technology particularly suitable for distributed hydrogen production using solar PV energy. However, to reach the cost targets for green hydrogen more R&D on PEMWE stacks and systems is required to improve the overall system efficiency, durability, and capital costs.Institute for Energy Technology (IFE) has designed and built a flexible PEM water electrolyzer system platform for testing of small-scale prototype electrolyzers up to 33 kW and 200 bar differential pressure. This PEMWE system laboratory is part of a national research infrastructure on hydrogen and fuel cells in Norway (NFCH Centre) at the IFE Hynor Hydrogen Technology Center (IFE Hynor) at Kjeller. The PEMWE test rig is integrated with a sophisticated power conditioning system which consists of three custom-built DC/DC-converters (for PEMWE, PEMFC, and Li-ion battery systems), all coupled to the same DC-bus. This configuration makes it possible to use the Li-ion battery system to test different hybrid electric topologies for the water electrolyzer system and to emulate different loads (e.g., grid load profiles, solar PV input). IFE has also installed a 16 kWp PV-system on the roof of the IFE Hynor research building, which can be connected to the DC-bus on a need basis.The one-of-a-kind high-pressure PEMWE test facility at IFE is very well suited to study the performances of next-generation PEMWE stacks and systems, and to tailor and test control strategies that safeguard the system and maximizes efficiency and durability when operated using variable power based on renewable energy. The standard delivery pressure of PEMWE systems is today around 30 bar, but to realize H2-generation systems at several hundred bars there are several challenges related to system operability and safety that need to be addressed and solved. The first design of the high-pressure PEMWE test facility at IFE was first presented at a conference two years ago (EFCF 2019). The system has now been completed and commissioned with a state-of-art prototype high-pressure (350 bar) PEMWE stack with a production capacity of 2 Nm3/h. Details of the final design and operational procedures will be presented together with results and data from the first high-pressure PEMWE-stack test campaigns. Figure 1

Particle Image Velocimetry measurements inside a tapered roller bearing with an outer ring made of sapphire: Design and operation of an innovative test rig

Experimental studies on rolling-element bearing lubrication represent an ambitious engineering challenge. In the present study, the design of a dedicated test rig to perform Particle Image Velocimetry (PIV) measurements on the lubricant inside a tapered roller bearing is presented. Through the usage of a sapphire outer ring, it has been possible to optically access the inside of a bearing without compromising its kinematics. PIV measurements allowed the reconstruction of the lubricant velocity field in the cavity between the cage and the outer ring at different rotational speeds. Results show that as the speed of rotation increases, bubbles due to aeration phenomena tend to appear and modify the behavior of the lubricant considerably.

Non-reactive test rig for combustor-turbine interaction studies in industrial gas turbines

Purpose This paper aims to present the design of a particular non-reactive test rig for combustion swirlers and first stage turbine nozzles. The test rig is required for important experimental activities aimed at the optimization of a specific class of gas turbines. Design/methodology/approach A multi-disciplinary team performed the design process by following a tailored design approach, which has been developed for the specific case. The design outcomes allowed to build a fully functional test rig to be introduced in a test cell and then to perform preliminary experiments about the fluid dynamic behaviour of the turbine elements. Findings The followed design approach allowed to efficiently perform the task, by supporting the information exchange among the different subjects involved in both the conceptual and the embodiment design of the test rig. Additionally, the performed experiments allowed to achieve a final configuration that makes the test rig a valuable test case for combustor-turbine interaction studies. Research limitations/implications The study described in this paper is focused on the design of a specific test rig, used for first validation tests. However, the achieved results (both in terms of design and test) constitutes the underpinning of the in-depth investigations to be performed in the next steps of the experimental campaign. Originality/value To the best of the authors’ knowledge, the present paper is the first one that comprehensively describes the design activity of an experimental test rig for turbine application, also providing indications about the specific methodological procedure used to manage the process.

The Research of Aircraft Fuel System Icing Test

When a civil aircraft is flying in high altitude and low temperature environment, once the fuel feed system freezes, the fuel pressure and flow of engine and APU will decrease, resulting in the loss of aircraft power and even the occurrence of flight accidents. In this paper, the icing test platform of aircraft fuel system is set up, the test configuration and measurement system design method are given. By carrying out icing test of a certain type of fuel system, the test results show the safety and rationality of the aircraft fuel system design and test rig design, so as to provide guidance and reference for the implementation of icing test of aircraft fuel system.

Taylor-Couette-Poiseuille flow heat transfer in a high Taylor number test rig

As technology advances, rotating machinery are operating at higher rotational speeds and increased pressures with greater heat concentration (i.e. smaller and hotter). This combination of factors increases structural stresses, while increasing the risk of exceeding temperature limits of components. To reduce stresses and protect components, it is necessary to have accurately designed thermal management systems with well-understood heat transfer characteristics. Currently, available heat transfer correlations operating within high Taylor number (above 1×10^10) flow regimes are lacking. In this work, the design of a high Taylor number flow experimental test rig is presented. A non-invasive methodology, used to capture the instantaneous heat flux of the rotating body, is also presented. Capability of the test rig, in conjunction with the use of high-density fluids, increases the maximum Taylor number beyond that of previous works. Data of two experiments are presented. The first, using air, with an operating Taylor number of 8.8± 0.8 ×10^7 and an effective Reynolds number of 4.2± 0.5 ×10^3, corresponds to a measured heat transfer coefficient of 1.67 ± 0.9 ×10^2 W/m2K and Nusselt number of 5.4± 1.5×10^1. The second, using supercritical carbon dioxide, demonstrates Taylor numbers achievable within the test rig of 1.32±0.8×10^12. A new correlation using air, with operating Taylor numbers between 7.4×10^6 and 8.9×10^8 is provided, comparing favourably with existing correlations within this operating range. A unique and systematic approach for evaluating the uncertainties is also presented, using the Monte-Carlo method.

A novel test rig to study the effect of fretting wear on the forced response dynamics with a friction contact

This paper presents a novel test rig to study the effect of fretting wear and of the contact surface evolution on the forced response of systems with dry friction contact. This rig allows simulating contacts similar to the type of contacts present between the shrouds at the blade tip. Several research groups have been studying how fretting wear affects the dynamic response of mechanical systems, developing numerical prediction tools that consider dry friction contact and nonlinearity. The aim of this work is to experimentally study the evolution of contact interfaces and how this evolution affects the system dynamics. Experimental results will aid to validate the numerical predictions. The test rig developed for this activity is made of a cantilever beam fixed at one end and with a friction contact at the free end. The contact couple is made of two replaceable specimens. The contact is loaded via a lifting mechanism through a screw with fine thread. Fretting wear test was performed at a constant frequency and force amplitude, exciting the beam with an electromagnetic shaker. To emphasize the change of the dynamic response, frequency sweeps were performed at various intervals during the wear test. The full range test with ‘changing preload’ due to progressing wear was performed until a full loss of contact. This paper describes the test rig design, intent, set-up, instrumentation, test plan and results. Results include the frequency response curves for unworn contact, wear profiles at multiple intervals and the effect of wear on the frequency response. Though energy dissipation per cycle is quite small, wear leads to material loss at the contact with a sufficiently large number of cumulative cycles and substantially affects the dynamic response. Results collected in this research activity are of particular importance to validate numerical tool that aim to simulate the dynamic behaviour of systems with dry friction contacts that undergo material loss caused by wear.

Data set generation at novel test-rig for validation of numerical models for modeling granular flows

Significant effort has been exerted on developing fast and reliable numerical models for modeling particulate flow; this is challenging owing to the complexity of such flows. To achieve this, reliable and high-quality experimental data are required for model development and validation. This study presents the design of a novel test-rig that allows the visualization and measurement of particle flow patterns during the collision of two particle streams. Valuable data sets are provided for the validation of numerical models dedicated to granular flows. The experimental work was conducted for three particle distributions and different configurations of the test rig setup. Additionally, a standard discrete element method for modeling particle transport was applied to the test-rig configuration and the effects of the material spring constant on the predicated flow patterns are investigated. An additional purpose of these simulations was also to collect necessary data for further collision model validation, developed based on a reduced-order technique.

Development of a floating liner test rig and lubrication model for the study of the piston compression ring friction force under fully flooded and starved lubrication

Advances in internal combustion engines make it necessary to study in depth their contribution to engine efficiency, and thus to friction mechanical losses, especially those generated in the piston-cylinder liner assembly. In this paper, the design of a novel test rig is presented, based on the floating liner principle, with the key objective of having the capability of developing multiple parameters tests in a relatively quick and easy way. The final design integrates a single-cylinder internal combustion engine, a mechanical solution that allows the liner to float, three piezoelectric force sensors and a novel design of lateral support based on ball transfer units. Reproducibility and repeatability of tests were assessed demonstrating the capability of the test rig to develop reliable friction measurements. Some parameters tests were developed to evaluate the sensitivity of the friction force measurements to variations in the working conditions, oil temperature and engine speed. A theoretical model for the piston compression ring is presented for both fully flooded and starved lubrication conditions, including asperity interactions and lubricant rheology. Comparisons of these approaches with experimental results showed that, for the working conditions of the test rig, lubrication of the compression ring is better estimated under fully flooded lubrication condition, as the starved lubrication analysis results in over-estimated friction force values at higher engine speed regimes.

Design and Research of New Type High-speed Hydrostatic Spindle Test Rig

Aiming at the air dynamic pressure foil bearing performance test rig, design and research a new high-speed static pressure spindle test rig. Carry out aerodynamic design of the driving turbine and compressor, obtain the three-dimensional impeller shape and carry out the strength calculation, design a new high-speed static pressure spindle test rig; use the finite element method to model the test bed rotor system, and use the transfer matrix method to analyse the shaft system structure critical speed and mode, so that the test rig can effectively avoid the critical speed and run stably. Analyse the unbalanced response and stability of the rotor system, and reasonably arrange the test rig device to achieve the purpose of measuring the performance of the dynamic pressure foil bearing, and ensure that the turbine static pressure spindle test rig can provide for the measurement of the air dynamic pressure foil bearing performance stable high speed.

Influence of Alternating Temperature Levels on the Wear Behavior of Radial Lip Seals: Test Rig Design and Wear Analysis

Influence of Alternating Temperature Levels on the Wear Behavior of Radial Lip Seals: Test Rig Design and Wear Analysis

КОНЦЕПЦИЯ МЕХАТРОННОЙ УСТАНОВКИ ДЛЯ ИССЛЕДОВАНИЯ РЕОЛОГИЧЕСКИХ СВОЙСТВ ФИЗИОЛОГИЧЕСКИХ ЖИДКОСТЕЙ

The properties of physiological fluids, blood primarily, contain important information about the state of a body. This article deals with the development of a new portable device of inertial viscometer for the physiological fluids. Based on the analysis of mathematical and simulation models of viscous media flows in capillaries, recommendations for the choice of design parameters are formulated. Processing the data of a video capillaroscopy for the intralipid flow under conditions close to the conditions for measuring blood viscosity showed the possibility of using the laser speckle contrast imaging method to determine the velocity profile over the channel thickness. The results obtained have created sufficient grounds for the design of a mechatronic test rig and its information-measuring system.