scholarly journals Influence of Miller cycle on thermal load of high-boosted diesel engine

2022 ◽  
Vol 14 (1) ◽  
pp. 168781402110709
Author(s):  
Ming Wen ◽  
Yufeng Li ◽  
Xiaojuan Li ◽  
Jinlong Liu ◽  
Juting Fan
Keyword(s):  
Thermal Load ◽  
Consumption Rate ◽  
Mechanical Load ◽  
Base Case ◽  
Miller Cycle ◽  
Intake Valve ◽  
Inlet Valve ◽  
Exhaust Temperature ◽  
Fuel Consumption Rate ◽  
Main Factors

With the increase of the engine intensified degree, mechanical load and thermal load become to the two main factors limiting the engine to intensify. Application of Miller cycle, which can be realized by late intake valve closing (LIVC) and deeper late intake valve closing (DLIVC), has the potential to reduce the effective CR, mechanical load, and thermal load. In this paper, the effects of LIVC and DLIVC on the mechanical load and thermal load of a boosted DI diesel are experimentally compared. Compared to the original base case, the average cylinder temperature of LIVC and DLIVC is reduced by 90 and 52 K. The exhaust temperature of LIVC and DLIVC decreased by 26 and 14 K, and the maximum combustion pressure of LIVC and DLIVC decreased by 1.6 and 9.7 bar. The pumping losses of LIVC and DLIVC are reduced by more than 25%, while the actual cycle power does not decrease due to the late closing of the inlet valve. The fuel consumption rate decreased from 250.1 g/kWh of base case to 240 g/kWh of LIVC, reduced by 4.0%. The indicated thermal efficiency increased from 41.9% of base case to 43.7% and 42.5% of LIVC and DLIVC. Miller loss is only 2.55% with Miller inlet phase.

Relating Burning Rate and NO Formation to Pressure Development in Two-Stroke Diesel Engines

1997 ◽  
Vol 119 (2) ◽  
pp. 129-136 ◽  
Author(s):  
P. G. Hill ◽  
B. Douville
Keyword(s):  
Diesel Engines ◽  
Consumption Rate ◽  
Mixing Time ◽  
Exhaust Temperature ◽  
Fuel Consumption Rate ◽  
No Formation ◽  
Combustion Properties ◽  
Crank Angle ◽  
Pressure Development ◽  
And Performance

A multizone thermodynamic method has been developed to determine combustion rate and NO formation from measured cylinder pressures and performance of two-stroke diesel engines. Integral to the analytical method is a nonlinear fit to the combustion chamber heat loss; the fit is consistent with the overall energy balance and with measured fuel consumption rate and exhaust temperature. The method assumes equilibrium combustion properties except for NO, whose relatively slow formation is estimated using the extended Zeldovich mechanism in the post-flame gas during a period of one mixing time. Application of the method to a 2-stroke diesel engine indicates a post-flame mixing time of 0.55 ms or 4 deg crank angle at 1250 rpm, yielding exhaust concentrations of NO considerably less than what would have been expected from equilibrium-then-sudden-freezing considerations.

A Study on Combustion Characteristics of Spark-Ignited Engine with Different Late Intake Valve Closing for Miller Cycle

2015 ◽  
Vol 20 (3) ◽  
pp. 141-148
Author(s):  
J.H. Chung ◽  
S.J. Kang ◽  
J.S. Kim ◽  
S.C. Jeong ◽  
J.W. Lee
Keyword(s):  
Combustion Characteristics ◽  
Miller Cycle ◽  
Intake Valve

Experimental Study on Urea Dosing Strategy for SCR on an Engine Fuelled with Bio-Diesel

2013 ◽  
Vol 848 ◽  
pp. 286-290 ◽  
Author(s):  
Hong Juan Ren ◽  
Di Ming Lou ◽  
Pi Qiang Tan ◽  
Zhi Yuan Hu
Keyword(s):  
Diesel Engine ◽  
Consumption Rate ◽  
Waste Cooking Oil ◽  
Conversion Ratio ◽  
Engine Torque ◽  
Average Value ◽  
Cooking Oil ◽  
Fuel Consumption Rate ◽  
Emission Standards ◽  
Dosing Strategy

Urea dosing strategy for SCR is studied for a diesel engine fuelled with bio-diesel BD20. Bio-diesel BD20 is consisted of biofuels made from waste cooking oil and national V diesel, and biofuels accounts for 20% by volume. The results show that, bio-diesel engine torque decreases by a maximum of 0.55%, brake fuel consumption rate increases by a maximum of 0.53% ,when the urea dosing strategy is adjusted and the engine and SCR are not changed. ESC tests show that, the maximum of NOXconversion ratio is 95%, the minimum is 57%, and the average value is 74% under ESC 12 conditions except idling, the maximum of HC decrease ratio is 74%, the minimum is 35%, and the average value is 55%, when the urea is dosed. NOXemission is 1.55 g/(kW·h) in ESC test, NOXemission is 2 g/(kW·h) in ETC test, and NH3slip is lower than 10×10-6, which proves that the NOXemission from the engine fuelled with BD20 can meet national emission standards V by adjusting the urea dosing strategy.

scholarly journals Design of new clean and efficient combustion mode and thermodynamics research using NSGA-II algorithm

2020 ◽  
Vol 24 (5 Part A) ◽  
pp. 2699-2706
Author(s):  
Guoqing Shen
Keyword(s):  
Natural Gas ◽  
Combustion Chamber ◽  
Fuel Consumption ◽  
Consumption Rate ◽  
Thermodynamic Characteristics ◽  
Dual Fuel ◽  
Combustion Mode ◽  
Nsga Ii ◽  
Fuel Consumption Rate ◽  
Efficient Combustion

In order to study a new clean and efficient combustion mode, which can relieve the pressure of traditional energy and ensure low emissions, in this study, a diesel/natural gas dual fuel engine is designed by non-dominant sorting genetic algorithm (NSGA-?), and its thermodynamic characteristics are studied. The WP10.290 Diesel engine is modified into a diesel/natural gas dual fuel engine. The emissions of harmful substances and thermal efficiency of the modified engine under different working conditions are compared. The combustion chamber structure and adaptability between combustion chamber and injection parameters are optimized by using NSGA-II algorithm and CFD software. The results show that the emission of NOx and CH4 and the fuel consumption rate can be reduced simultaneously by using the composite combustion model compared with the original engine. When the CH4 emission is close to zero, the fuel consumption rate decreases obviously, and NOx slightly increases. When the angle between the injection holes is 141.57? the amount of NOx in the cylinder is large. When the injection advance angle is 21.91?CA, the pressure in the cylinder is the highest, the CH4 production is the lowest, the NOx production is higher, and the oxygen content in the combustion mixture is less. The NOx production is the lowest. diesel/natural gas dual fuel engine can ensure efficient combustion while reducing emissions. In this study, the performance of the dual fuel engine at various speeds can be further studied, which can provide theoretical support for the design of diesel/natural gas dual fuel engine.

scholarly journals Multi-Objective Techno-Economic Optimization of Design Parameters for Residential Buildings in Different Climate Zones

2021 ◽  
Vol 14 (1) ◽  
pp. 65
Author(s):  
Muhammad Usman ◽  
Georg Frey
Keyword(s):  
Thermal Load ◽  
Energy Demand ◽  
Residential Buildings ◽  
Optimal Solution ◽  
Building Envelope ◽  
Design Parameters ◽  
Base Case ◽  
Economic Optimization ◽  
Single Family ◽  
Climate Zones

The comprehensive approach for a building envelope design involves building performance simulations, which are time-consuming and require knowledge of complicated processes. In addition, climate variation makes the selection of these parameters more complex. The paper aims to establish guidelines for determining a single-family household’s unique optimal passive design in various climate zones worldwide. For this purpose, a bi-objective optimization is performed for twenty-four locations in twenty climates by coupling TRNSYS and a non-dominated sorting genetic algorithm (NSGA-III) using the Python program. The optimization process generates Pareto fronts of thermal load and investment cost to identify the optimum design options for the insulation level of the envelope, window aperture for passive cooling, window-to-wall ratio (WWR), shading fraction, radiation-based shading control, and building orientation. The goal is to find a feasible trade-off between thermal energy demand and the cost of thermal insulation. This is achieved using multi-criteria decision making (MCDM) through criteria importance using intercriteria correlation (CRITIC) and the technique for order preference by similarity to ideal solution (TOPSIS). The results demonstrate that an optimal envelope design remarkably improves the thermal load compared to the base case of previous envelope design practices. However, the weather conditions strongly influence the design parameters. The research findings set a benchmark for energy-efficient household envelopes in the investigated climates. The optimal solution sets also provide a criterion for selecting the ranges of envelope design parameters according to the space heating and cooling demands of the climate zone.

Performance of biomass combustor based drying system for ginger drying

2021 ◽  
Vol 45 (01) ◽  
pp. 19-25
Author(s):  
D. K. Vyas ◽  
N. Seth ◽  
J. J. Chavda
Keyword(s):  
Fuel Consumption ◽  
Flow Rate ◽  
Consumption Rate ◽  
Air Flow ◽  
Air Flow Rate ◽  
Saw Dust ◽  
Fuel Consumption Rate ◽  
Hot Air ◽  
Drying System ◽  
Maize Cobs

A biomass combustor based dryer was evaluated with different biomass for drying of ginger. Biomass combustor based dryer consists of fuel hopper, combustion chamber, heat exchanger, grate for proper combustion of the combustible gas, chimney, ambient air inlet, hot air outlet and drying chamber. The system was evaluated at five fuel consumption rate (1 to 5 kg.h–1) and five air flow rate (100, 150, 200, 300 and 400 m3.h–1) using maize cobs, sized wood and saw dust briquettes for ginger drying. The experimental performances show that the hot air temperature inside the dryer vary between 36 to 81ºC for maize cobs, 53 to 85ºC for sized wood and 49 to 87ºC for biomass briquettes at tested air flow rate and fuel consumption rate in the system. The maximum efficiency of the system was found at the fuel consumption rate of 1 kg.h–1 and 400 m3.h–1 air flow rate using maize cobs, sized wood and saw dust briquettes as fuel respectively. The cost of operation of ginger drying at 1 kg.h–1 fuel consumption rate and 400 m3/h air flow rate was Rs. 32.76, 34.26, 34.76 and 55 per hour using maize cobs, sized wood, saw dust briquettes and mechanical drying system, respectively. Hence, the drying of ginger in biomass combustor based dryer using maize cobs at 1 kg.h–1 fuel consumption rate and 400 m3/h air flow rate resulted in better performance.

Study on the Application of Marine Biodiesel on High Speed Diesel Engines

2011 ◽  
Vol 287-290 ◽  
pp. 1976-1979
Author(s):  
Lin Cai Ma ◽  
Zhi Guo Zhou ◽  
Liang Yao Xia ◽  
Da Xue Liu ◽  
Xiao Li Yu
Keyword(s):  
Diesel Engine ◽  
High Speed ◽  
Consumption Rate ◽  
Effective Power ◽  
Engine Load ◽  
Bench Tests ◽  
Fuel Consumption Rate ◽  
High Speed Diesel ◽  
Hc Emissions ◽  
Load Conditions

A bench tests were carried out on an YC6J190 diesel engine fueled with B20 marine biodiesel. The results showed that the engine’s effective power decreased by 1.8%, the fuel consumption rate increased by 0.07%, HC emissions decreased by 19.17% and the soot decreased by 25% as average under full engine load conditions. HC decreased by 23.4% and the soot decreased by 23% as average under part engine load conditions. The soot emissions decreased by 28.8% as average under the free acceleration conditions.

Probabilistic Assessment of Combustor Liner Design

1995 ◽  
Author(s):  
Shantaram S. Pai ◽  
Christos C. Chamis
Keyword(s):  
Thermal Load ◽  
Mechanical Load ◽  
Coefficient Of Thermal Expansion ◽  
Probabilistic Assessment ◽  
Vibration Frequencies ◽  
Combined Stress ◽  
Liner Material ◽  
Load Profile ◽  
Local Stresses ◽  
Combustor Liner

A typical hot structural component within an engine such as composite combustor liner is computationally simulated and probabilistically evaluated in view of the numerous uncertainties associated with the structural, material, and thermo-mechanical load variables (primitive variables) that describe the combustor. The combustor is evaluated for buckling (eigenvalue) loads, vibration frequencies, and local stresses. Results show that the scatter in the combined stress is not uniform along the length of the combustor. Furthermore, coefficient of thermal expansion, hoop modulus of the liner material, and the thermal load profile dominate stresses near the support and the intermediate location of the combustor liner. However, the liner thickness, the liner material hoop modulus, and pressure load profile have significant impact on stresses near the free end of combustor.

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