Engine Test Method Research Articles

Failure mechanism analysis and support strength determination of deep coal mine roadways – A case study

In order to solve the problems related to deformations, failures, and difficulties in support controls of deep coal mine roadways, the typical failure forms and characteristics of deep coal mine roadways were investigated and analyzed in this study. The distribution laws of plastic zones of circular roadways under different lateral pressure coefficients were expounded using a theoretical analysis method, and the influence of plastic zone scopes on the failure forms of roadways was explained. In addition, considering the distribution characteristics of plastic zones, a calculation method of the required support strength based on the plastic zone scopes was proposed. The primary and secondary factors affecting the support strength were then determined. A numerical simulation method was applied in order to analyze the distribution characteristics of the displacements and plastic zones of deep mine circular roadways under the conditions of no support scheme, an existing support scheme, and a support scheme determined by the proposed support strength calculation method (referred to in this study as the optimized support scheme), respectively. The simulation results showed that the support effects of the optimized support scheme were superior to those of the existing support scheme, and thereby more conducive to maintaining roadway stability. In addition, an on-site engineering test method was used to identify support schemes for bolting and shotcrete with wire mesh + concrete-filled steel tubular supports based on the plastic zone scopes and the support strength of roadways in order to determine the support parameters. As indicated by the field monitoring results, the proposed support strength calculation method and optimized support scheme had shown the ability to effectively control the large deformations of the tested roadway, and thereby guarantee its overall stability.

Characteristics and mechanism of large deformation of squeezing tunnel in phyllite stratum

The Maoxian Tunnel in Sichuan, China has experienced significant deformation and supporting failure in the surrounding phyllite rock. To address this problem, on-site engineering geological investigation and testing methods were deployed in the present study to examine the characteristics and mechanism of deformation in the tunnel. Scanning electron microscopy, rock hydraulic tests, and uniaxial compressive tests were used to investigate the hydraulic and mechanical properties of the surrounding rock, and to examine the mechanisms underlying the significant deformation. The results suggest that the large deformation in Maoxian Tunnel is a result of shear expansion and progressive failure of the soft rock under high stress. To enhance the integrity and self-sustaining ability of the rock mass, it is necessary to promptly construct support structures and reinforce the surrounding rock.

Methods and Advances in the Design, Testing and Development of In Vitro Diagnostic Instruments

With the continuous improvement of medical testing and instrumentation engineering technologies, the design, testing and development methods of in vitro diagnostic instruments are developing rapidly. In vitro diagnostic instruments are also gradually developing into a class of typical high-end medical equipment. The design of in vitro diagnostic instruments involves a variety of medical diagnostic methods and biochemical, physical and other related technologies, and its development process involves complex system engineering. This paper systematically organizes and summarizes the design, testing and development methods of in vitro diagnostic instruments and their development in recent years, focusing on summarizing the related technologies and core aspects of the R&D process, and analyzes the development trend of the in vitro diagnostic instrument market.

Development and Application of an Engine Test Method to Rate the Internal Injector Deposit Formation of Diesel Fuels and Additives

<div class="section abstract"><div class="htmlview paragraph">Design efforts to improve the hydraulic efficiency of high-pressure diesel fuel systems and thus further improve overall engine efficiency have resulted in the utilisation of low-spill control valves and reduced injector component clearances to reduce general leakage losses. Overall, these advances have contributed significantly to the high efficiency diesel engines of today. However, the combination of very high fuel pressures, cavitation and low fuel leakage volumes increases the heating of the remaining fuel, increasing temperature and, in turn, the propensity for deposits to form inside the injector. This deposit phenomenon is commonly known as Internal Diesel Injector Deposits (IDID) and can cause rough engine running and failed engine starts requiring injector cleaning or replacement. Methods studying this phenomenon are under development in the industry. Meanwhile this paper describes the development and application of an in-house engine test method to rate the IDID control performance of deposit control additives (DCA). A 2.0L, 4-cylinder light-duty engine is run with a fuel containing a contaminant to provoke the occurrence of deposit formation within a reasonable test duration. In ‘keep clean’ test mode the performance of the DCA is assessed based on its ability to prevent IDID symptoms that routinely manifest in unadditivated test runs, primarily between-cylinder deviation in exhaust port gas temperature as the operation of individual injectors is impaired by deposits. In ‘clean up’ test mode the DCA is assessed on its ability to reverse IDID symptoms that manifested in a preceding unadditivated test run. In initial tests the methodology has proved capable of differentiating between a novel DCA chemistry that exhibits good IDID control behaviour in keep clean and clean up modes and a conventional DCA chemistry that did not. Temperature deviations were reduced applying the novel DCA at premium dose in keep clean mode. In clean up mode, temperature deviations were reduced from the end of dirty up to the end of clean up, with premium plus dose rate of the novel DCA. In both cases the improvements were statistically significant at the 95% confidence level.</div></div>

Моторные масла для двухтактных бензиновых двигателей

The article considers the design and lubrication of small 2-stroke engines installed on snowmobiles, quad bikes, motorcycles and drones. The compositions of the 2-stroke engine oils, base oils and additives, actual specification JASO, NMMA, API, TISI and ISO are analysed. Concern the short characteristics of JASO engine test methods.

Development of an Engine Test to Rate the EGR Deposit Formation Propensity of Fuels in Light-Duty Diesel Engines

<div class="section abstract"><div class="htmlview paragraph">Exhaust Gas Recirculation (EGR) is employed in diesel engines to reduce engine-out NOx. Carbon-containing deposits form in the EGR systems of modern diesel engines as the particulate matter, hydrocarbons and other entrained species deposit from the exhaust gas flow as it cools. Much work has been done by Original Equipment Manufacturers (OEMs) to reduce deposits and mitigate their effects by optimized dimensioning of EGR coolers and valves, introduction of EGR cooler bypass for use in the most sensitive cold conditions and experimenting with oxidation catalysts upstream of the EGR system. Nevertheless, deposits forming in the high-pressure Exhaust Gas Recirculation (HP-EGR) systems of modern diesel engines can sometimes lead to a number of problems including emissions and fuel consumption deterioration, poor performance and drivability, as well as breakdowns. An engine test method has been developed to enable the impact of fuel on deposits in the HP-EGR system to be studied. This paper describes the work undertaken in the test development and initial fuel effects testing to prove the discriminatory power of the method. In the test method a 4-cylinder light-duty diesel engine of 1.6L displacement runs at conditions conducive to EGR deposit formation over 24 hours and the impact of fuels on deposit formation is determined through weighing of the EGR system components before and after the test. Initial tests comparing a B7 representative of European EN590 diesel fuel and a Fischer-Tropsch Gas-to-Liquid (GTL) gasoil fuel showed that 72% less deposit formed with GTL than with B7. This work provides a foundation for further study of fuel effects on EGR deposits.</div></div>

Experimental research on fatigue performance of aero-structure under two combined loads

In this paper, a new engineering test method which put forward the initial stage of aircraft design, bearing both acoustic and static loads, is carried out in Lab. From currently test effect, it could accurately simulate the real situation of aircraft panel under hydrostatic load and acoustic load, and the test result shows that the structure presents plastic deformation under the combined action of acoustic load and static load, which differs from the common failure mode of the structure under the action of the single strong noise load. Furthermore, the proposed method could provide guidance to support aircraft type selection.

Trends in automotive emissions legislation: impact on LD engine development, fuels, lubricants, and test methods – a global view, with a focus on WLTP and RDE regulations – Summary of the 6th International Exhaust Emissions Symposium (IEES)

Among the drivers influencing vehicular powertrain development, the field of vehicular exhaust emissions is experiencing wide-ranging and rapid changes. New emissions regulations such as Euro 6d and new test methods (RDE and WLTP) are the main challenges for the automotive industry caused by political, socioeconomic and technical factors. Air quality is very high on the political agenda and pressure remains to limit and reduce greenhouse gas emissions from the road transport sector. In addition to limits becoming increasingly stringent, the list of parameters subject to legal limits are slowly expanding – and, most importantly, these limits must be met under a wide range of conditions. A range of strategies are available to overcome these difficulties, which was explored during the 6th International Exhaust Emissions Symposium (IEES) hosted at BOSMAL in June 2018. This paper reports and summarises the topics of the 6th IEES and attempts a synthesis on the current status of the field of IC engines, hybrid powertrains and electric vehicles and what the coming years may hold for the automotive and fuel industries and other allied fields.

Structural Engineering Test for Determining the Circumferential Modulus of Circular Pipes and Tubes

Abstract This article proposes a structural engineering test method for determining the transverse flexural modulus of circular tubes and pipes made from fiber-reinforced polymer composite. The computed modulus from the proposed test can be used both in the design and in the qualification and acceptance procedures of these structural components. To validate the proposed test method, experiments were conducted on 23 metallic and 4 carbon fiber-reinforced polymer composite rings having different material properties, diameters, and thicknesses. In addition, three different test setups and measurement techniques were used where each ring was subjected to two collinear tension forces while recording both the force and the change-in-diameter along the line of action of the two forces. The recorded data was then used to compute the transverse moduli of the circular tubes. The transverse modulus values determined from the proposed test were compared with those obtained from material tensile and flexural coupon tests carried out on the same tube materials. The three test setups and measurement techniques yielded satisfactory results, suggesting that the proposed test method is viable for adoption in both laboratory and field testing while balancing its ease of use and cost.

The Development of Fuel Economy Test Method for Heavy Duty Diesel Engine Oil (The First HD Engine Test Method and the New JASO DH-2F Category)

The Development of Fuel Economy Test Method for Heavy Duty Diesel Engine Oil (The First HD Engine Test Method and the New JASO DH-2F Category)

Investigation of a Proposed Four Storey Building Sites Using Geophysical and Laboratory Engineering Testing Methods in Lagos, Nigeria

The spate of engineering structures collapse in Lagos metropolis with its attendant loss of lives and properties has assumed an alarming proportion in recent times. Efforts to mitigate such incidence has necessitated an integrated geophysical and geotechnical investigation of a proposed four storey building sites with a view to determine the suitability of the site for the proposed project. Resistivity investigation, un-drained multi-stage triaxial compression and oedometer consolidation tests were carried out to determine the engineering properties of the subsurface. The results revealed peaty clay to silty sand materials characterized by 35kN/m 2 75kN/m 2 cohesion values, (5°-13°) internal friction, 29.3% 64.5% natural water content and 1.652 – 1.972 Mg/m 3 bulk density. The allowable bearing capacity of 50 kN/m 2 , volume compressibility from 0.115 m 2 /MN to 0.666 m 2 /MN, initial void ratio and consolidation coefficient of 0.779 1.381 and 2.7 m 2 /year 8.3 m 2 /year respectively on the pressure range of 0 to 400 kN/m 2 and estimated settlement values of 114 to 273 mm were obtained for the site materials. These results are indicative of soft to stiff clays and presence of sands and silts in the essentially clayey deposit. The study area is thus underlain by extensive zone of ductile and low strength founding materials having medium to high compressibility and settlement value that exceeds the tolerable limit suitable for founding a four storey building and should therefore be avoided. These characteristics preclude the use of conventional shallow foundations, piles or vibro-replacement up

500Ps급 상용차량 디젤엔진을 이용한 선박용 디젤엔진 개발 연구

This study was carried out to develop a diesel engine for marine propulsion. This marine diesel engine was developed based on a 500Ps vehicle diesel engine. Many main parts, such as the intercooler, radiator, and engine controller were designed for the marine diesel engine. The intercooler was designed to be of sea water cooling type; inlet air is cooled by sea water. Engine coolant is cooled by sea water in the radiator too. The water cooling heat exchanger has high cooling performance. In the cooling system, consists of the intercooler and the radiator, the sea water passes through the intercooler and then the radiator, in sequence. This process is very effective compared to the reverse method in which sea water passes through the radiator and then the intercooler, in sequence. The control performance of the engine controller and the fuel injection rate were improved using an engine speed controller. This system was tested on an engine dynamometer and an exhaust gas analyzer using the marine diesel engine test method. Test results show that the 500Ps marine diesel engine satisfied the IMO NOx regulations; Tier II.

Field Methods for Characterizing Weak Rock for Engineering

Research Article| January 01, 2006 Field Methods for Characterizing Weak Rock for Engineering PAUL M. SANTI PAUL M. SANTI 1Department of Geological Engineering, Colorado School of Mines, Golden, CO 80401 Search for other works by this author on: GSW Google Scholar Environmental & Engineering Geoscience (2006) 12 (1): 1–11. https://doi.org/10.2113/12.1.1 Article history first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation PAUL M. SANTI; Field Methods for Characterizing Weak Rock for Engineering. Environmental & Engineering Geoscience 2006;; 12 (1): 1–11. doi: https://doi.org/10.2113/12.1.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract Many classification and testing methods for shale, slaking rock, weak rock, and weathered rock have been developed. However, few of these methods are suitable for field use or are applicable to a wide range of material types. The purpose of this paper is to present a summary of recent research and analysis evaluating classification and testing methods. This summary will assist the practitioner in properly identifying problem shale and weak rock units, in adequately describing their characteristics in the field, and in selecting and performing field tests to quantify their behavior. For identification of shale and weak rock units, three increasingly site-specific tools are presented. First is a map showing occurrences of weak rock units in the United States. Second is a detailed list of suspect rock types that may appear on regional or local geologic maps. Third is a summary of engineering properties that describe weak rock units, based on a review of technical literature. Some of these properties are compressive strengths between 1 and 20 MPa, slake durability less than 90 percent, clay content greater than 15 percent, poor induration, a significant amount (50 to 75 percent) of matrix between hard blocks, or high moisture content. Methods of field description were chosen based on a review of existing methods to assess their ease of application, breadth of application, and the usefulness of the engineering properties indicated by each system. Two modified methods are presented to indicate proportion and nature of corestones and matrix, strength, influence of discontinuities, and reactivity to water. Finally, field-testing methods that estimate strength, permeability, durability, and reaction to water are identified. These include point load index, Norwegian Geotechnical Institute Rock Mass Classification, jar slake, and hammer rebound classification. Predictive equations to estimate unconfined compressive strength, slake durability, and slake index are given. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

On Raleigh Equation and Accuracy of its Real Roots Calculations

Composite materials require adequate means of nondestructive testing, evaluation, and monitoring. Ultrasonic methods and tools are one means to meet these objectives. The latest advances of electrical and electronic engineering and nondestructive testing methods provide the foundation for a wide class of modern ultrasonic equipment. However, some recent experimental results require reevaluation of existing basic theories, especially in the field of acoustic wave propagation. More accurate calculations of the real roots of the Rayleigh equation with their value approximations by different polynomials given in this paper may be useful for improvement of nondestructive testing of materials. This work also considers additional roots of the Rayleigh equation as a basis for new types of surface waves.

AN ENGINEERING METHOD TO EVALUATE THE CRISP TEXTURE OF FRUIT AND VEGETABLES

ABSTRACTPrecise measurements of the deformation and fracture behaviour of food can be difficult because of problems associated with the produce, for example, sample preparation, gripping, size and geometry. The aim of this study was to characterise fruits and vegetables in terms of fracture properties using an established engineering test method and geometry, the Single‐Edge Notched Bend (SENB). The SENB geometry was found to be readily applicable to crisp food produce such as carrots, celery, and apples, which exhibit linear elastic behaviour up to fracture. Fracture toughness and fracture energies were found to be in the range 10–50 kPa m1/2 and 40–400 Jm−2, respectively. The structure of these materials was confirmed, using confocal microscopy, and related to the observed fracture behaviour. Cell size and intercellular spaces influenced the values of fracture toughness and fracture energy.

Establishment of engine test method for evaluating detergency performance of automobile diesel engine oils

A joint program between JALOS (Japanese Lubricating Oil Society) and JASO (Japanese Automobile Standards Organization) has established a “next generation” piston detergency test method for diesel engine oils aimed at impending low emission diesel engine hardware in Japan. Three test methods were examined with three different engines. The results showed that each method could discriminate the performance level of the oils tested. Finally, the IDI (NA) engine of Nissan Diesel TD25 was chosen for the new JASO detergency test method. As well as having high-temperature and high-load test conditions it has the twin advantages of easy handling in operation and good availability of engine parts for the future.

An investigation of the effectiveness of antifriction additives in motor oils by laboratory methods and engine tests

AbstractThe antifriction properties of motor oils with different additives (oil soluble metal‐containing compounds, molybdenum disulphide and graphite dispersions, and ashless additives) were investigated by means of laboratory methods. The influence of additive concentration on their effectiveness is evaluated. The effect of the action of antifriction additives (friction modifiers) depends on the base oil and motor oil additive packages. The results of experiments are analysed using Auger spectroscopy. A mechanism of action of different types of friction modifiers based on analysis of the experimental data is proposed. Diesel engine tests of motor oils with antifriction additives were used to show the influence of these additives on fuel consumption. The results of engine tests with oils with different additives, and tests conducted on laboratory friction‐machines, are compared. A description of the laboratory methods and engine test methods used, as well as recommendations for their practical use in evaluating antifriction properties of motor oil additives, is given.

Engine test method for qualification of oils for low-speed marine diesels

Engine test method for qualification of oils for low-speed marine diesels

A comparative performance study of vehicle, static engine and synthetically aged autocatalysts using cvs, static engine and synthetic gas rig testing methods

The relative performances of on-road, static engine and furnace aged autocatalysts were measured using three established testing methods. Similar trends were noted between vehicle and static engine evaluation data. Perturbed lambda scan data generated on static engine and synthetic gas rig apparatus also showed good correlation. However, on-road aged catalysts were found to be far more severely deactivated than those subjected to laboratory accelerated ageing.

An improved engineering test method for measurement of the compressive strength of unidirectional carbon fibre composites

A modified test coupon has been developed for measurement of the compressive strength of unidirectional composite materials. The coupon proposed has a machined gauge length 8 mm long with integrally moulded end tabs of 0°/+/−45° construction. Strengths were measured on the new coupon and found to lead to improvements of over 50% compared with the CRAG standard method. In addition, all failures occurred within the gauge lengths instead of at the end tabs. Failure stresses were in keeping with the stresses achieved in the 0° layers of laminates loaded to compressive failure. It is therefore strongly recommended that laboratories make use of the waisted coupon proposed in this work to generate unidirectional compressive strength design data for composite materials. In addition, it is recommended that the standards bodies seriously consider modifying their approved test method for unidirectional compressive strength and consider adopting the coupon design proposed in this work.