scholarly journals Oil Coking Prevention Using Electric Water Pump for Turbo-Charge Spark-Ignition Engines

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Han-Ching Lin ◽  
Yen-Tso Chang ◽  
Go-Long Tsai ◽  
Dao-Ming Wang ◽  
Feng-Chi Hsieh ◽  
...  
Keyword(s):  
Combustion Engine ◽  
Operating Temperature ◽  
Spark Ignition Engines ◽  
Water Pump ◽  
Turbo Charge ◽  
Electric Water Pump ◽  
Higher Temperature ◽  
Lower Temperature ◽  
And Control ◽  
System Layout

Turbocharger has been widely implemented for internal combustion engine to increase an engine's power output and reduce fuel consumption. However, its operating temperature would rise to 340°C when engine stalls. This higher temperature may results in bearing wear, run-out, and stick, due to oil coking and insufficient lubrication. In order to overcome these problems, this paper employs Electric Water Pump (EWP) to supply cool liquid to turbocharger actively when the engine stalls. The system layout, operating timing, and duration of EWP are investigated for obtaining optimal performance. The primarily experimental results show that the proposed layout and control strategy have a lower temperature of 100°C than the conventional temperature 225°C.

scholarly journals Socio-Economic and Environmental Risk Factors of Tuberculosis in Wonosobo, Central Java, Indonesia

2020 ◽  
Vol 16 (1) ◽  
pp. 61-70
Author(s):  
Rita Dian Pratiwi ◽  
Dibyo Pramono ◽  
Junaedi Junaedi
Keyword(s):  
Risk Factors ◽  
Population Density ◽  
Environmental Risk ◽  
Basic Education ◽  
Environmental Risk Factors ◽  
Central Java ◽  
Personal Ventilation ◽  
Higher Temperature ◽  
Lower Temperature ◽  
And Control

This study discusses the dominant socio-economic and environmental risk factors for TB disease. The design of this study was a case-control study with 70 case samples and control with a contribution of n = 1. Variables from this study contacted personal, ventilation of the house, humidity, the temperature of the house, density of the house, kitchen, and family earnings. Multivariate data analysis uses multiple logistic regressions. The study notes that from 140 samples, 47% have basic education, and 30% are farmers. People who had a past of contact with TB cases were ten times more likely to contract TB than those who had no contacted (OR = 10.00; p <0.001). Personalities who live in poorly ventilated homes who have a risk of contracting TB are 2.2 times greater than those who live in homes with standard ventilation (OR = 2.20; p <0.018). The moisture increases the risk of TB by four times the low moisture (OR = 4.00; p = 0.001). Living in a house with a higher temperature of TB is 3.8 times higher than a lower temperature (OR = 3.80; p = 0.009). Living in a high population density of the house improves TB five times more than living in a lesser home (OR = 5.00; p <0.001). Kitchen gas enhances the risk of TB 2.5 times greater than gasless (OR = 2.50; p = 0.007). Low family earnings raise the risk of TB three times greater than high family earnings (OR = 3.00; p = 0.002). A past of contact, poorly ventilated homes, high humidity, hothouse temperature, population density, kitchen gas, and low family earnings, are risk factors for TB in Wonosobo, Central Java.

scholarly journals Sprouting of Sorghum (Sorghum bicolor [L.] Moench): Effect of Drying Treatment on Protein and Starch Features

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 407 ◽  
Author(s):  
Mia Marchini ◽  
Alessandra Marti ◽  
Claudia Folli ◽  
Barbara Prandi ◽  
Tommaso Ganino ◽  
...  
Keyword(s):  
Food Production ◽  
Cost Effective ◽  
High Exposure ◽  
Effective Technology ◽  
Drying Treatment ◽  
Higher Temperature ◽  
Lower Temperature ◽  
The One ◽  
Drying Conditions ◽  
Sorghum Bicolor L

The nutritional and physicochemical properties of sorghum proteins and starch make the use of this cereal for food production challenging. Sprouting is a cost-effective technology to improve the nutritional and functional profile of grains. Two drying treatments were used after sorghum sprouting to investigate whether the drying phase could improve the protein and starch functionalities. Results showed that the drying treatment at lower temperature/longer time (40 °C for 12 h) extended the enzymatic activity that started during sprouting compared to the one performed at higher temperature/shorter time (50 °C for 6 h). An increased protein hydrolysis and water- and oil-holding capacity were found in the flour obtained by the former treatment. Higher protein matrix hydrolysis caused high exposure of starch to enzymes, thus increasing its digestibility, while worsening the technological functionality. Overall, modulating drying conditions could represent a further way, in addition to sprouting, to improve sorghum flour’s nutritional profile.

MICROSTRUCTURAL EVOLUTION OF Al-Cu-Mg-Ag ALLOY WITH TRACE Zr ADDITION DURING TWO-STEP HOMOGENIZATION

2009 ◽  
Vol 23 (06n07) ◽  
pp. 855-862 ◽  
Author(s):  
FEIYUE MA ◽  
ZHIYI LIU
Keyword(s):  
Melting Point ◽  
Grain Boundaries ◽  
Microstructural Evolution ◽  
Cast Alloy ◽  
Scanning Calorimetry ◽  
Zr Addition ◽  
Homogenization Time ◽  
The Matrix ◽  
Higher Temperature ◽  
Lower Temperature

The microstructural evolution in an Al - Cu - Mg - Ag alloy with trace Zr addition during homogenization treatment was characterized by Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray Spectroscopy (EDS). It was shown that the low-melting-point phase segregating toward grain boundaries is Al 2 Cu , with a melting point of 523.52°C. A two-step homogenization process was employed to optimize the microstructure of the as-cast alloy, during which the alloy was first homogenized at a lower temperature, then at a higher temperature. After homogenized at 420°C for 6 h, Al 3 Zr particles were finely formed in the matrix. After that, when the alloy was homogenized at an elevated temperature for a longer time, i.e., 515°C for 24 h, most of the precipates at the grain boundaries were removed. Furthermore, the dispersive Al 3 Zr precipitates were retained, without coarsening greatly in the final homogenization step. A kinetics model is employed to predict the optimal homogenization time at a given temperature theoretically, and it confirms the result in present study, which is 420°C/6h+515°C/24h.

Stirling Engine Technology for Parabolic Dish-Stirling System Based on Concentrating Solar Power (CSP)

2015 ◽  
Vol 785 ◽  
pp. 576-580 ◽  
Author(s):  
Liaw Geok Pheng ◽  
Rosnani Affandi ◽  
Mohd Ruddin Ab Ghani ◽  
Chin Kim Gan ◽  
Jano Zanariah
Keyword(s):  
High Efficiency ◽  
Combustion Engine ◽  
Renewable Energy Sources ◽  
Stirling Engine ◽  
Energy Sources ◽  
Heat Engines ◽  
Stirling Engines ◽  
Parabolic Dish ◽  
Mechanical Devices ◽  
And Control

Solar energy is one of the more attractive renewable energy sources that can be used as an input energy source for heat engines. In fact, any heat energy sources can be used with the Stirling engine. Stirling engines are mechanical devices working theoretically on the Stirling cycle, or its modifications, in which compressible fluids, such as air, hydrogen, helium, nitrogen or even vapors, are used as working fluids. When comparing with the internal combustion engine, the Stirling engine offers possibility for having high efficiency engine with less exhaust emissions. However, this paper analyzes the basic background of Stirling engine and reviews its existing literature pertaining to dynamic model and control system for parabolic dish-stirling (PD) system.

scholarly journals Research on the Static Recrystallization and Precipitation Behaviors of a V-N Microalloyed Steel

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Baochun Zhao ◽  
Tan Zhao ◽  
Guiyan Li ◽  
Qiang Lu
Keyword(s):  
Static Recrystallization ◽  
Microalloyed Steel ◽  
Time Interval ◽  
Main Role ◽  
Recrystallization Process ◽  
Compression Tests ◽  
Double Compression ◽  
Higher Temperature ◽  
Lower Temperature ◽  
Temperature Strain

Double compression tests were performed on a Gleeble-3800 thermomechanical simulator to study the softening behaviors of deformed austenite in a V-N microalloyed steel. The static recrystallization volume fractions were calculated by stress offset method, and the kinetic model of static recrystallization was constructed. The effects of temperature, strain, and time interval on the softening behaviors were analyzed, and the interactions between precipitation and recrystallization were discussed. The results show that the softening behaviors of the deformed austenite at lower temperature or higher temperature are markedly different. At the temperature of 850°C or 800°C, pinning effects of the precipitates play the main role, and the recrystallization process is inhibited, which leads to the formation of plateaus in the softening curves. An increase in strain promotes the precipitation and recrystallization processes while reduces the inhibition effect of precipitation on recrystallization as well.

Effects of Sr Addition on Mechanical Properties and Microstructure of Mg-6Al Magnesium Alloy

2011 ◽  
Vol 686 ◽  
pp. 120-124
Author(s):  
Jin Ping Fan ◽  
She Bin Wang ◽  
Bing She Xu
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Magnesium Alloy ◽  
Strengthening Mechanism ◽  
Microstructure And Mechanical Properties ◽  
Higher Temperature ◽  
Lower Temperature

The effects of Sr addition on the mechanical properties and microstructure of Mg-6Al mag- nesium alloy both at 25 °C and at 175 °C were investigated by means of OM, SEM and EDS and XRD. Upon the Sr addition of 2%, the tensile strength was increased by 7.2% to 184.4MPa at 25 °C, while it was increased by 30% to 155.4MPa at 175 °C. The strengthening mechanism of Mg-6Al-xSr at lower temperature (25 °C) was different from that at higher temperature (175°C). The results show that the addition of strontium effectively improved the microstructure and mechanical properties of magnesium alloy.

Heat Transport Limitation of a Triangular Micro Heat Pipe

2003 ◽  
Author(s):  
D. Sugumar ◽  
Kek Kiong Tio
Keyword(s):  
Heat Pipe ◽  
Heat Transport ◽  
Operating Temperature ◽  
Working Fluid ◽  
Transport Capacity ◽  
Condenser Section ◽  
Micro Heat Pipe ◽  
Evaporator Section ◽  
Higher Temperature ◽  
Specific Temperature

A micro heat pipe will operate effectively by achieving its maximum possible heat transport capacity only if it is to operate at a specific temperature, i.e., design temperature. In reality, micro heat pipe’s may be required to operate at temperatures different from the design temperature. In this study, the heat transport capacity of an equilateral triangle micro heat pipe is investigated. The micro heat pipe is filled optimally with working fluid for a specific design temperature and operated at different operating temperatures. For this purpose, water, pentane and acetone was selected as the working fluids. From the numerical results obtained, it shows that the optimal charge level of the micro heat pipe is dependent on the operating temperature. Furthermore, the results also shows that if the micro heat pipe is to be operated at temperatures other than its design temperature, its heat transport capacity is limited by the occurrence of flooding at the condenser section or dryout at the evaporator section, depending on the operating temperature and type of working fluid. It is observed that when the micro heat pipe is operated at a higher temperature than its design temperature, the heat transport capacity increases but limited by the onset of dryout at the evaporator section. However, the heat transport capacity decreases if it is to be operated at lower temperatures than its design temperature due to the occurrence of flooding at condenser end. From the results obtained, we can conclude that the performance of a micro heat pipe is decreased if it is to be operated at temperatures other than its design temperature.

Experimental Investigation on the Rubbing Process of Labyrinth Seals Considering the Material Combination

2020 ◽  
Author(s):  
Lisa Hühn ◽  
Oliver Munz ◽  
Corina Schwitzke ◽  
Hans-Jörg Bauer
Keyword(s):  
Turbine Blades ◽  
Design Guidelines ◽  
Operating Conditions ◽  
Contact Forces ◽  
Experimental Investigations ◽  
Process Data ◽  
Labyrinth Seals ◽  
Material Combination ◽  
Higher Temperature ◽  
And Control

Abstract Labyrinth seals are used to prevent and control the mass flow rate between rotating components. Due to thermally and mechanically induced expansions during operation and transient flight maneuvers, a contact, the so-called rubbing process, between rotor and stator cannot be excluded. A large amount of rubbing process data concerning numerical and experimental investigations is available in public literature as well as at the Institute of Thermal Turbomachinery (ITS). The investigations were carried out for different operating conditions, material combinations, and component geometries. In combination with the experiments presented in this paper, the effects of the different variables on load due to rubbing are compared, and discussed with the focus lying on the material combination. The influence of the material on the loads can be identified as detailed as never before. For example, the contact forces in the current experiments are higher due to a higher temperature resistance of Young’s modulus. The analysis will also be based on the rubbing of turbine blades. Design guidelines are derived for labyrinth seals with improved properties regarding tolerance of rub events. Based on the knowledge obtained, guidelines for designing reliable labyrinth seals for future engines are discussed.

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