Angular Torque Methodology for Cylinder Head Bolted Joint and Validation by FE and Experimental Work

Author(s):  
Abhijeet Vithal Marathe ◽  
Neelkanth V. Marathe ◽  
G. Venkatachalam

Cylinder Head Gasketed joint is one of the important joint for internal combustion engines. The main function of cylinder Head Gasketed joint is to seal combustion gases, oil and coolant and avoid entering the air into combustion chamber. Preload is applied on cylinder head bolt to avoid the leakages. Excessive preload on cylinder head bolt will cause extra stresses and cylinder bore deformation also increased which reduces the engine performance. Hence, it is very essential to determine adequate and accurate preload on cylinder head bolts. There are different types of bolt tightening methods followed by engine manufacturers as compared to other methods loss of preload and preload variation is less in angle torque method. In this work, Angle torque method for cylinder head bolted joint classical mathematical model is developed to estimate the snug torque and angle torque. Model is validated with FE analysis and experimental work. High performance 3-cylinder diesel engine's cylinder head, cylinder head bolts and crankcase are taken for methodology development, FE and experimental work.

Lubricants ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 19
Author(s):  
Sofia Orjuela Abril ◽  
Carlos Pardo García ◽  
Jhon Pabón León

Currently, internal combustion engines contribute to the problem of global warming due to their need to use products derived from fossil resources. To mitigate the above problem, this study proposes the use of coatings on the cylinder bore in order to reduce fuel consumption and polluting emissions. Therefore, in the present study a numerical model is developed in which the tribological behavior, heat fluxes, and leakage of the combustion gases in the chamber are considered to evaluate the influence of the coating. Nickel nanocomposite (NNC) and diamond-like carbon (DLC) coatings are considered in the study. The results demonstrate that the NNC coating produces a 32% reduction in the total friction force of the compression ring. The estimated maximum temperatures for the lubricating oil were 214, 202, and 194 °C for the DLC, steel, and NNC materials. Increasing the temperature in the DLC coating can cause a reduction in the tribological performance of the lubricant. The estimates made show that the implementation of the NNC coating allows a maximum reduction of 5.28 ton of fuel and 39.30 kg of CO emissions, which are based on the global fleet of diesel engines forecast for the year 2025 (corresponding to one hundred and eighty million engines) and a test time of 1800 s. The proposed numerical model allows future analyses to be carried out for other types of materials used as coatings. Additionally, the model can be expanded and adapted to consider other systems that involve friction processes in the engine.


Author(s):  
Michael Forder ◽  
Jamal Umer ◽  
Nicholas Morris ◽  
Ramin Rahmani ◽  
Sebastian Howell-Smith ◽  
...  

Parasitic frictional losses in internal combustion engines of race vehicles adversely affect their performance. A significant proportion of these losses occur within the piston-cylinder system. This paper presents a study of the compatibility of cylinder bore surface materials with typical lubricant base constituent stock (poly alpha olefin and polyolester) as well as a fully formulated lubricant. Nanoscale boundary friction is measured using lateral force microscopy. The effect of material properties, nanoscale roughness and lubricant species upon underlying mechanisms of generated friction is presented. Advanced cylinder materials and coatings and lubricant molecular species used for high performance engines are investigated, and an integrated approach not hitherto reported in literature.


Author(s):  
S. Menon ◽  
K. Weyer ◽  
D. Pedersen ◽  
C. Hagen

Natural gas is an attractive option for transportation applications in the United States due to its abundant availability and potential for reduced emissions. The scarcity of refueling resources imposes a barrier to widespread use of natural gas in internal combustion engines. The development of a novel bi-modal engine capable of operating in a compressor mode provides refueling capabilities without any supplemental devices and attempts to overcome this infrastructure limited barrier. Heat generated in the compression process however results in undesirable effects such as increased work input for compression, pre-heating of natural gas stored in the fuel tank, and thermal loads in the components used in the modified cylinder head. In order to make the system self-contained, heat exchangers that utilize engine coolant as a heat sink are included in the system design to maintain natural gas temperatures at an acceptable level in between compression stages. This is planned to be done in a novel fashion so as to make the system self-regulating permitting the cooling of natural gas while maintaining the coolant temperature in the cylinder head at acceptable levels to maintain combustion efficiency. To this end, an EES model of the system that incorporates elements of the original vehicle coolant system and modifications made to incorporate the heat exchangers is developed and analyzed to ensure satisfactory performance. Parametric studies of system performance as a function of varying heat loads are used to determine the best strategy to maintain acceptable natural gas temperatures without causing a drop in engine performance.


Author(s):  
Badal Dev Roy ◽  
R. Saravanan

The Turbocharger is a charge booster for internal combustion engines to ensure best engine performance at all speeds and road conditions especially at the higher load.  Random selection of turbocharger may lead to negative effects like surge and choke in the breathing of the engine. Appropriate selection or match of the turbocharger (Turbomatching) is a tedious task and expensive. But perfect match gives many distinguished advantages and it is a one time task per the engine kind. This study focuses to match the turbocharger to desired engine by simulation and on road test. The objective of work is to find the appropriateness of matching of turbochargers with trim 67 (B60J67), trim 68 (B60J68),  trim 70 (A58N70) and trim 72 (A58N72) for the TATA 497 TCIC -BS III engine. In the road-test (data-logger method) the road routes like highway and slope up were considered for evaluation. The operating conditions with respect various speeds, routes and simulated outputs were compared with the help of compressor map.


Author(s):  
Yuh-Yih Wu ◽  
Ching-Tzan Jang ◽  
Bo-Liang Chen

Homogeneous charge compression ignition (HCCI) is recognized as an advanced combustion system for internal combustion engines that reduces fuel consumption and exhaust emissions. This work studied a 150 cc air-cooled, four-stroke motorcycle engine employing HCCI combustion. The compression ratio was increased from 10.5 to 12.4 by modifying the cylinder head. Kerosene fuel was used without intake air heating and operated at various excess air ratios (λ), engine speeds, and exhaust gas recirculation (EGR) rates. Combustion characteristics and emissions on the target engine were measured. It was found that keeping the cylinder head temperature at around 120–130°C is important for conducting a stable experiment. Two-stage ignition was observed from the heat release rate curve, which was calculated from cylinder pressure. Higher λ or EGR causes lower peak pressure, lower maximum rate of pressure rise (MRPR), and higher emission of CO. However, EGR is better than λ for decreasing the peak pressure and MRPR without deteriorating the engine output. Advancing the timing of peak pressure causes high peak pressure, and hence increases MRPR. The timing of peak pressure around 10–15 degree of crank angle after top dead center indicates a good appearance for low MRPR.


2021 ◽  
pp. 146808742110583
Author(s):  
Ioannis Nikiforakis ◽  
Zhongnan Ran ◽  
Michael Sprengel ◽  
John Brackett ◽  
Guy Babbit ◽  
...  

Solid oxide fuel cells (SOFCs) have been deployed in hybrid decentralized energy systems, in which they are directly coupled to internal combustion engines (ICEs). Prior research indicated that the anode tailgas exiting the SOFC stack should be additionally exploited due to its high energy value, with typical ICE operation favoring hybridization due to matching thermodynamic conditions during operation. Consequently, extensive research has been performed, in which engines are positioned downstream the SOFC subsystem, operating in several modes of combustion, with the most prevalent being homogeneous compression ignition (HCCI) and spark ignition (SI). Experiments were performed in a 3-cylinder ICE operating in the latter modus operandi, where the anode tailgas was assimilated by mixing syngas (H2: 33.9%, CO: 15.6%, CO2: 50.5%) with three different water vapor flowrates in the engine’s intake. While increased vapor content significantly undermined engine performance, brake thermal efficiency (BTE) surpassed 34% in the best case scenario, which outperformed the majority of engines operating under similar operating conditions, as determined from the conducted literature review. Nevertheless, the best performing application was identified operating under HCCI, in which diesel reformates assimilating SOFC anode tailgas, fueled a heavy duty ICE (17:1), and gross indicated thermal efficiency ([Formula: see text]) of 48.8% was achieved, with the same engine exhibiting identical performance when operating in reactivity-controlled compression ignition (RCCI). Overall, emissions in terms of NOx and CO were minimal, especially in SI engines, while unburned hydrocarbons (UHC) were non-existent due to the absence of hydrocarbons in the assessed reformates.


Author(s):  
Federico Perini ◽  
Anand Krishnasamy ◽  
Youngchul Ra ◽  
Rolf D. Reitz

The need for more efficient and environmentally sustainable internal combustion engines is driving research towards the need to consider more realistic models for both fuel physics and chemistry. As far as compression ignition engines are concerned, phenomenological or lumped fuel models are unreliable to capture spray and combustion strategies outside of their validation domains — typically, high-pressure injection and high-temperature combustion. Furthermore, the development of variable-reactivity combustion strategies also creates the need to model comprehensively different hydrocarbon families even in single fuel surrogates. From the computational point of view, challenges to achieving practical simulation times arise from the dimensions of the reaction mechanism, that can be of hundreds species even if hydrocarbon families are lumped into representative compounds, and thus modeled with non-elementary, skeletal reaction pathways. In this case, it is also impossible to pursue further mechanism reductions to lower dimensions. CPU times for integrating chemical kinetics in internal combustion engine simulations ultimately scale with the number of cells in the grid, and with the cube number of species in the reaction mechanism. In the present work, two approaches to reduce the demands of engine simulations with detailed chemistry are presented. The first one addresses the demands due to the solution of the chemistry ODE system, and features the adoption of SpeedCHEM, a newly developed chemistry package that solves chemical kinetics using sparse analytical Jacobians. The second one aims to reduce the number of chemistry calculations by binning the CFD cells of the engine grid into a subset of clusters, where chemistry is solved and then mapped back to the original domain. In particular, a high-dimensional representation of the chemical state space is adopted for keeping track of the different fuel components, and a newly developed bounding-box-constrained k-means algorithm is used to subdivide the cells into reactively homogeneous clusters. The approaches have been tested on a number of simulations featuring multi-component diesel fuel surrogates, and different engine grids. The results show that significant CPU time reductions, of about one order of magnitude, can be achieved without loss of accuracy in both engine performance and emissions predictions, prompting for their applicability to more refined or full-sized engine grids.


Author(s):  
Jin Hyung Cho ◽  
Johan Martinsson ◽  
Du Sichen ◽  
Joo Hyun Park

AbstractNi-based superalloy, which has excellent high-temperature strength and corrosion resistance, is mainly used in aviation materials, high-performance internal combustion engines, and turbines for thermal and nuclear power generation. For this reason, refining the impurities in Ni-based superalloys is a very important technical task. Nevertheless, the original technology for the melting and refining of Ni-based superalloys is still insufficient. Therefore, in this study, the effect of the CaO-Al2O3-MgO-TiO2 slag on the removal efficiency of an impurity element sulfur in Incoloy® 825 superalloy, one of the representative Ni-based superalloys, was investigated. The desulfurization behavior according to the change of TiO2 content and CaO/Al2O3 (=C/A, basicity) ratio as experimental variables was observed at 1773 K (1500 °C). Although the TiO2 content in the slag increases to 15 mass pct, the mass transfer coefficient of sulfur in molten alloy showed a constant value. Alternatively, under the condition of C/A > 1.0 of slag, the mass transfer coefficient of sulfur showed a constant value, whereas under the condition of C/A < 1.0, the mass transfer coefficient of sulfur greatly decreased as CaO decreased. Hence, in the desulfurization of Incoloy® 825 superalloy using the CaO-Al2O3-MgO-TiO2 slag, the TiO2 content in the slag does not have a considerable effect on the desulfurization rate and desulfurization mechanism (metal phase mass transfer controlled regime), but the basicity of the slag has a significant effect on desulfurization mechanism. When the slag basicity decreases below the critical level, i.e., C/A < 1.0, which is corresponding to sulfur distribution ratio, Ls < 200, it was confirmed that the desulfurization mechanism shifts from the metal phase mass transfer-controlled regime to the slag phase mass transfer-controlled regime due to the variation in the physicochemical properties of the slag such as viscosity and sulfide capacity. In addition, the different desulfurization rates between steel and Ni alloy melts were discussed by employing the diffusivity of sulfur in both systems.


2021 ◽  
Vol 8 (1) ◽  
pp. H16-H20
Author(s):  
A.V.N.S. Kiran ◽  
B. Ramanjaneyulu ◽  
M. Lokanath M. ◽  
S. Nagendra ◽  
G.E. Balachander

An increase in fuel utilization to internal combustion engines, variation in gasoline price, reduction of the fossil fuels and natural resources, needs less carbon content in fuel to find an alternative fuel. This paper presents a comparative study of various gasoline blends in a single-cylinder two-stroke SI engine. The present experimental investigation with gasoline blends of butanol and propanol and magnesium partially stabilized zirconium (Mg-PSZ) as thermal barrier coating on piston crown of 100 µm. The samples of gasoline blends were blended with petrol in 1:4 ratios: 20 % of butanol and 80 % of gasoline; 20 % of propanol and 80 % of gasoline. In this work, the following engine characteristics of brake thermal efficiency (BTH), specific fuel consumption (SFC), HC, and CO emissions were measured for both coated and non-coated pistons. Experiments have shown that the thermal efficiency is increased by 2.2 % at P20. The specific fuel consumption is minimized by 2.2 % at P20. Exhaust emissions are minimized by 2.0 % of HC and 2.4 % of CO at B20. The results strongly indicate that the combination of thermal barrier coatings and gasoline blends can improve engine performance and reduce exhaust emissions.


Author(s):  
Prashant Srinivasan ◽  
Sanketh Bhat ◽  
Manthram Sivasubramaniam ◽  
Ravi Methekar ◽  
Maruthi Devarakonda ◽  
...  

Large bore reciprocating internal combustion engines are used in a wide variety of applications such as power generation, transportation, gas compression, mechanical drives, and mining. Each application has its own unique requirements that influence the engine design & control strategy. The system architecture & control strategy play a key role in meeting the requirements. Traditionally, control design has come in at a later stage of the development process, when the system design is almost frozen. Furthermore, transient performance requirements have not always been considered adequately at early design stages for large engines, thus limiting achievable controller performance. With rapid advances in engine modeling capability, it has now become possible to accurately simulate engine behavior in steady-states and transients. In this paper, we propose an integrated model-based approach to system design & control of reciprocating engines and outline ideas, processes and real-world case studies for the same. Key benefits of this approach include optimized engine performance in terms of efficiency, transient response, emissions, system and cost optimization, tools to evaluate various concepts before engine build thus leading to significant reduction in development time & cost.


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