Research and Improvement of Muffler Acoustic Characteristics with Regard to Thermodynamic Characteristics of Exhaust Gas Flow with Aeroacoustic Sources

Emission control devices such as selective catalytic reduction (SCR), exhaust gas recirculation (EGR), and scrubbers were installed in the compression ignition (CI) engine, and flow analysis of intake air and exhaust gas was required to predict the performance of the CI engine and emission control devices. In order to analyze such gas flow, it was inefficient to comprehensively analyze the engine’s cylinder and intake/exhaust systems because it takes a lot of computation time. Therefore, there is a need for a method that can quickly calculate the gas flow of the CI engine in order to shorten the development process of emission control devices. It can be efficient and quickly calculated if only the parts that require detailed observation among the intake/exhaust gas flow of the CI engine are analyzed in a 3D approach and the rest are analyzed in a 1D approach. In this study, an algorithm for gas flow analysis was developed by coupling 1D and 3D in the valve systems and comparing with experimental results for validation. Analyzing the intake/exhaust gas flow of the CI engine in a 3D approach took about 7 days for computation, but using the developed 1D–3D coupling algorithm, it could be computed within 30 min. Compared with the experimental results, the exhaust pipe pressure occurred an error within 1.80%, confirming the accuracy and it was possible to observe the detailed flow by showing the contour results for the part analyzed in the 3D zone. As a result, it was possible to accurately and quickly calculate the gas flow of the CI engine using the 1D–3D coupling algorithm applied to the valve system, and it was expected that it can be used to shorten the process for analyzing emission control devices, including predicting the performance of the CI engine.

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Studi Penggunaan Variable Speed Drive Untuk Pengaturan Kecepatan Motor Exhaust Fan Pada Dyno Test Room PT. Trakindo Utama Pekanbaru

JURNAL TEKNIK ◽

10.31849/teknik.v12i2.1755 ◽

2018 ◽

Vol 12 (2) ◽

pp. 85-96

Author(s):

Elham Prasetyo Wibowo ◽

Elvira Zondra ◽

Usaha Situmeang

Keyword(s):

Power Consumption ◽

Induction Motor ◽

Gas Flow ◽

Air Flow ◽

Load Test ◽

Exhaust Gas ◽

Variable Speed ◽

Variable Speed Drive ◽

Combustion Gas ◽

Motor Exhaust

ABSTRAK Exhaust fan adalah peralatan berupa sudu-sudu yang berputar dan memanfaatkan gaya sentrifugal untuk membuang exhaust gas hasil pembakaran bahan bakar solar engine diesel pada saat dilakukan tes pembebanan penuh. Dengan exhaust fan, gas karbondioksida yang dihasilkan oleh engine diesel memungkinkan untuk dibuang dengan cepat sehingga tidak memenuhi ruangan dan membahayakan bagi setiap karyawan. Pengoperasian exhaust fan dilakukan sesuai jadwal pengetesan engine. Exhaust fan tersebut digerakkan oleh motor induksi 3 phasa 30 kW dengan putaran nominal secara konstan. Pada saat pengetesan engine dengan nilai aliran gas buang yang rendah, exhaust fan tetap dioperasikan dengan kecepatan nominal. Operasional motor exhaust fan dengan kecepatan konstan seperti ini akan mengakibatkan konsumsi daya listrik yang relatif tinggi dari pada motor dengan kecepatan berubah-ubah sesuai kebutuhan. Sebagai pertimbangan hasil perhitungan untuk engine C 18 Caterpillar kapasitas 831 hp yang sebelumya membutuhkan operasional exhaust fan dengan daya 24,7927 kW nilai sama untuk semua model engine, setelah penggunaan VSD dapat dikurangi sebesar 14,35 % menjadi 21,2343 kW saja. Penelitian ini bertujuan mendapatkan probabilitas hubungan antara konsumsi energi listrik, frekuensi pada variable speed drive, putaran motor induksi dan nilai aliran udara pada cerobong exhaust fan. Nilai aliran udara exhaust fan tersebut akan disesuaikan dengan nilai aliran gas pembakaran yang dihasilkan oleh engine. Analisa optimasi motor exhaust fan ini sedianya akan menggunakan Matematic Analysis dan simulasi menggunakan simulink matlab sehingga diharapkan ada solusi untuk melakukan penghematan terhadap konsumsi daya motor, kemudian bisa diterapkan dalam semua pengoperasian motor yang ada di perusahaan. Kata kunci : variable speed drive, motor induksi, exhaust fan ABSTRACT The exhaust fan is a rotary blade device which produces centrifugal force to remove exhaust gas from diesel fuel combustion during a full load test. With exhaust fans, the carbondioxide gases that generated by the diesel engine allows to be disposed quickly so that it does not fill the room and harm to every employee. The operation of exhaust fan is carried out according to the engine test schedule. The exhaust fan is driven by a 3 phase induction motor of 30 kW with constant rotation. When testing the engine with a low Exhaust Gas flow value, the exhaust fan remains operated at rated speed. Operational exhaust fan with a constant speed like this will result in relatively high power consumption of the motor with the speed of change as needed. Considering the calculation results for C 18 engine Caterpillar capacity of 831 hp which previously required operational exhaust fan with 24,7927 kW of equal value for all engine models, after the use of VSD can be reduced by 14.35% to 21.2343 kW only. This study aims to obtain the probability of relationship between electrical energy consumption, frequency on the variable speed drive, induction motor rotation and the value of air flow in the exhaust fan chimney. The value of the exhaust fan air flow will be adjusted to the combustion gas flow value generated by the engine. The optimization analysis of this motor exhaust fan will be using Matematic Analysis and simulation using matlab simulink so it is expected there is a solution to make savings to motor power consumption, then it can be applied in all the motor operation in the company. Keywords: variable speed drive, induction motor, exhaust fan

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Second Law Analysis of a Stirling Cryocooler With Optimal Design of the Regenerator and Losses

10.1115/imece2001/pid-25621 ◽

2001 ◽

Author(s):

E. D. Rogdakis ◽

N. A. Bormpilas

Keyword(s):

Gas Flow ◽

Optimization Technique ◽

Internal Heat ◽

Thermodynamic Characteristics ◽

Coefficient Of Performance ◽

Solid Matrix ◽

Second Law ◽

External Temperature ◽

Technical Requirements ◽

Second Law Analysis

Abstract The aim of the research in this paper is a second law analysis of a Stirling cryocooler. A one-dimensional model is proposed for the simulation of the gas flow in the expansion space, the regenerator, the warm-end, the compression space and the compressor. Helium gas is selected as the working medium. An algorithm has been developed considering parametrically the most from the main operational tasks of the thermodynamic cycle. Performance indices such as heat input, efficiency, external dimensions of the engine and technical requirements are taken into account as constraints. Engine operating parameters i.e. speed, external temperature, mean pressure are fixed. The regenerator loss has a critical influence on the cryocooler efficiency and the reduction of this kind of internal irreversibilities is extremely difficult due to the generator is subject to rapidly cycling flows accompanied by steep temperature gradients and large pressure variations. The second flow analysis of the regenerator identifies two principal losses, the irreversible internal heat transfer into the solid matrix and the hydraulic resistance. An optimization technique leads to entropy generation charts, extremely useful for a good design of the regenerator. Finally the main thermodynamic characteristics (net refrigeration, power input and the coefficient of performance) of the cryocooler are given both cases with and without external and internal irreversibilities.

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Monitoring of CO2 exchange during cardiopulmonary bypass: the effect of oxygenator design on the applicability of capnometry

Perfusion ◽

10.1177/026765919300800409 ◽

1993 ◽

Vol 8 (4) ◽

pp. 337-344 ◽

Cited By ~ 3

Author(s):

Juha Aittomäki

Keyword(s):

Cardiopulmonary Bypass ◽

Gas Flow ◽

Blood Gases ◽

Barometric Pressure ◽

Co2 Exchange ◽

Arterial Line ◽

Exhaust Gas ◽

Blood Samples ◽

Outlet Port ◽

Membrane Oxygenators

The correlation between pCO2 values in blood and in exhaust gas from the oxygenators was examined during cardiopulmonary bypass (CPB) using one bubble oxygenator and three membrane oxygenators. Forty-seven CPBs were performed, 17 with Compactflow® (Dideco, ltaly), 10 with Maxima® (Medtronic Inc., USA), 10 with Cobe CML®(Cobe Laboratories, USA) membrane oxygenators and 10 with Hi-Flex® (Dideco, Italy) bubble oxygenators. Blood samples were taken both from arterial and venous lines of the oxygenator. A capnometer was connected to the oxygenator gas exhaust port and CO2 fraction was measured at the time of drawing blood samples. CO2 pressure in the gas phase was calculated from the product of the CO2 fraction and water vapour- corrected barometric pressure. Blood gases were measured at 37°C and the pCO2 value was corrected to the temperature of the arterial line. The correlation between blood and exhaust gas pCO2 was good in all the oxygenators examined, ranging from 0.921 to 0.976. The standard error of estimate (SEE) was in the range of about ± 2 mmHg for all the oxygenators. The systematic error (slope and intercept of the correlation line) varied depending on the construction of the oxygenator, with countercurrent design having the best overall correspondence. Based on the results of this study it can be concluded that arterial or venous CO 2 pressure can be monitored with a capnometry device coupled to the oxygenator gas outlet port. The use of a 'target FCO2 line' or a calculator program is proposed in order to aid the perfusionist in adjusting the oxygenator gas flow to attain normocarbia during CPB.

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Assessment of a Syngas-Diesel Dual Fuelled Compression Ignition Engine

ASME 2010 4th International Conference on Energy Sustainability, Volume 1 ◽

10.1115/es2010-90218 ◽

2010 ◽

Cited By ~ 4

Author(s):

Bibhuti B. Sahoo ◽

Niranjan Sahoo ◽

Ujjwal K. Saha

Keyword(s):

Diesel Engine ◽

Thermal Efficiency ◽

Gas Flow ◽

Direct Injection ◽

Dual Fuel ◽

Exhaust Gas ◽

Compression Ignition ◽

Gas Temperature ◽

Compression Ignition Engine ◽

Exhaust Gas Temperature

Synthesis gas (Syngas), a mixture of hydrogen and carbon monoxide, can be manufactured from natural gas, coal, petroleum, biomass, and even from organic wastes. It can substitute fossil diesel as an alternative gaseous fuel in compression ignition engines under dual fuel operation route. Experiments were conducted in a single cylinder, constant speed and direct injection diesel engine fuelled with syngas-diesel in dual fuel mode. The engine is designed to develop a power output of 5.2 kW at its rated speed of 1500 rpm under variable loads with inducted syngas fuel having H2 to CO ratio of 1:1 by volume. Diesel fuel as a pilot was injected into the engine in the conventional manner. The diesel engine was run at varying loads of 20, 40, 60, 80 and 100%. The performance of dual fuel engine is assessed by parameters such as thermal efficiency, exhaust gas temperature, diesel replacement rate, gas flow rate, peak cylinder pressure, exhaust O2 and emissions like NOx, CO and HC. Dual fuel operation showed a decrease in brake thermal efficiency from 16.1% to a maximum of 20.92% at 80% load. The maximum diesel substitution by syngas was found 58.77% at minimum exhaust O2 availability condition of 80% engine load. The NOx level was reduced from 144 ppm to 103 ppm for syngas-diesel mode at the best efficiency point. Due to poor combustion efficiency of dual fuel operation, there were increases in CO and HC emissions throughout the range of engine test loads. The decrease in peak pressure causes the exhaust gas temperature to rise at all loads of dual fuel operation. The present investigation provides some useful indications of using syngas fuel in a diesel engine under dual fuel operation.

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The use of low grade bio ethanol as fuel mixer in gasoline engine with optimization compact distillator

E3S Web of Conferences ◽

10.1051/e3sconf/20186702004 ◽

2018 ◽

Vol 67 ◽

pp. 02004

Author(s):

Iqbal Yamin ◽

Bambang Sugiarto ◽

Setia Abikusna ◽

Dedi Suntoro

Keyword(s):

Alternative Energy ◽

Gas Flow ◽

Gasoline Engine ◽

Ethanol Vapor ◽

Energy Development ◽

Green Energy ◽

Low Grade ◽

Exhaust Gas ◽

High Grade ◽

Alternative Energy Sources

Limited fossil energy resources need to encourage renewable energy development and energy conservation it is called green energy development. One of the alternative energy sources used are bioethanol, from low grade is converted into high grade through distillation process with distillator compact that will be used as a mixture of gasoline. Tests compact distillator consisting of evaporator Indonesia Kampus, separator, and condenser by utilizing exhaust gas to heat distillator already filled with low grade bioethanol, so the heat transfer occurs on the surface of the exhaust into the evaporator chamber. In the evaporator will transform ethanol into the vapor phase. Ethanol vapor flows into the separator, with a mechanism in it is expected that water vapor will evaporate participate separately with ethanol vapor. Ethanol vapors from this distillation will flow to the condenser and will be turned into liquid, the liquid is as high grade bioethanol would be the fuel mixing gasoline. In early studies, distillation rate was 98.5 ml/h with 67% ethanol content. Optimization compact distillator is done by adding the valve at the evaporator branch. When heat has reached 80°C exhaust gas flow to the evaporator chamber is closed. As a result, the heat from the evaporator can be detained and not rise significantly. Further optimization is to change the design of the separator through theoretical and empirical calculations with some assumptions based on the rule of thumb in the field of distillation, adding insulation to reduce heat leakage, as well as varying the feed volume and feed concentrate ethanol. In the end, based on the parameters of the distillation rate and ethanol concentrate, compact distillator with distances between tray 100 mm, volume 800 ml, engine speed 5.400 rpm can produce distillation rate of 274.3 ml/hr and ethanol concentrate of 88.97%.

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Analysis of exhaust gas flow through a particulate filter in the exhaust of the spark ignition direct injection engine

10.1063/1.5092091 ◽

2019 ◽

Author(s):

Paweł Fuć ◽

Piotr Lijewski ◽

Barbara Sokolnicka ◽

Maciej Siedlecki ◽

Natalia Szymlet

Keyword(s):

Gas Flow ◽

Direct Injection ◽

Spark Ignition ◽

Particulate Filter ◽

Exhaust Gas ◽

Direct Injection Engine ◽

Flow Through

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Identification of character of flow realized in low power heating boilers

E3S Web of Conferences ◽

10.1051/e3sconf/201912801008 ◽

2019 ◽

Vol 128 ◽

pp. 01008

Author(s):

Wojciech Judt ◽

Bartosz Ciupek ◽

Rafał Urbaniak

Keyword(s):

Heat Transfer ◽

Low Power ◽

Transfer Process ◽

Gas Flow ◽

Heat Transfer Process ◽

Vertical Position ◽

Exhaust Gas ◽

Flow Through ◽

Heating Boiler ◽

Different Levels

An analysis of a heat transfer process during exhaust gas flow through two boiler draughts connected in the reversing chamber is presented. The article shows the main differences in the exhaustgas flowthrough the boiler construction when heating boiler works with different levels of heating power.The aim of the proposed research is defining a character of a flow and a heat transfer process depending onthe horizontal and vertical position of boiler draughts.

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Analyzing Fluid Elastic Instability of Vibrating Tubes Failure at HRSG Steam Generator by Adopting Criteria of ASME Sec III Div.1 App. N-1330

Volume 8: Heat Transfer and Thermal Engineering ◽

10.1115/imece2016-66340 ◽

2016 ◽

Author(s):

Adel M. Al-Nasser

Keyword(s):

Steam Generator ◽

Vortex Shedding ◽

Gas Flow ◽

Dynamic Instability ◽

Acoustic Vibration ◽

Structural Vibration ◽

Damping Factor ◽

Exhaust Gas ◽

Acoustic Frequency ◽

Critical Instability

Current study analyzes dynamic instability of evaporator tube array at heat recovery steam-generator (HRSG) that encounters repetitive tube vibration failure. The tube array experiences turbulent swirling flue-gas. The analysis according to ASME criteria predicts critical instability velocities at 26.2 m/s, dimensionless reduced velocity factor at 85.7 and dimensionless mass damping at 50.2. These levels create large response of high vibration amplitude of tube reflecting strong coupling between tube structure and exhaust gas. CFD model for exhaust gas flow regime upstream tube array predicts large variation in velocity. The model is not validated but results agree with experience of repetitive tube failure within the high velocity profile sections. The calculated natural frequency of tube is 6 Hz, dimensionless reduced mass damping factor of tube is found at 243 meeting ASME criterion of greater than 64. Thus, synchronous vortex shedding vibration will not occur at the tube. Last, HRSG encounters structural vibration, cracks and high noise level at stack side. Fundamental acoustic frequency and vortex shedding frequency are calculated at 65 Hz and 134 Hz, respectively. These values don’t meet 80–120% range. Thus acoustic vibration noise will not occur.

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