Blow-By Truck Application: Electrically Driven Cone Stack Separator for Crankcase Ventilation

2007 ◽  
Author(s):  
Gerd Kissner ◽  
Hartmut Sauter
Keyword(s):  
Separation Efficiency ◽  
Ventilation System ◽  
Motor Vehicles ◽  
Cylinder Wall ◽  
Oil Consumption ◽  
Control Laws ◽  
Crankcase Ventilation ◽  
Oil Fraction ◽  
Air Intake ◽  
Oil Mist

Dealing with the blow-by gas from reciprocating engine is a bigger challenge nowadays due to strict emission control laws and design limitations. Blow-by gas originates between the piston or piston rings and the cylinder wall and is charged with oil when it leaves the crankcase. In a closed crankcase ventilation system these blow-by gases are drawn from the crankcase into the air intake. The oil mist separator (OMS) retains a fraction of the liquid oil and returns the retained oil fraction back to the oil sump. Thus, the oil mist separator reduces oil consumption and emissions. Electrically driven cone stack separators have high separation efficiency, small differential pressure, arbitrary mounting position and low power consumption. In addition to that, the electrically driven cone stack separator has also advantageous control characteristics. Since commercial motor vehicles already have high electrical system requirements a Mechatroic concept is presented here which was developed to be maintenance-free over the lifetime of the engine. This is achieved by detailed design and choice of special materials. In this paper, the construction and application of the novel oil mist separator system for trucks are discussed in detail.

Liner Design to Reduce Unburned Hydrocarbon Exhaust Emissions

2018 ◽  
Author(s):  
Paul S. Wang ◽  
Allen Y. Chen
Keyword(s):  
Natural Gas ◽  
Ventilation System ◽  
Hydrocarbon Emissions ◽  
Tracer Technique ◽  
Oil Consumption ◽  
Natural Gas Engines ◽  
Unburned Hydrocarbon ◽  
Crankcase Ventilation ◽  
Unburned Fuel ◽  
Careful Design

Large natural gas engines that introduce premixed fuel and air into the engine cylinders allow a small fraction of fuel to evade combustion, which is undesirable. The premixed fuel and air combust via flame propagation. Ahead of the flame front, the unburned fuel and air are driven into crevices, where conditions are not favorable for oxidation. The unburned fuel is a form of waste and a source of potent greenhouse gas emissions. A concept to vent unburned fuel into the crankcase through built-in slots in the liner during the expansion stroke has been tested. This venting process occurs before the exhaust valve opens and the unburned fuel sent into the crankcase can be recycled to the intake side through a closed crankcase ventilation system. The increased communication between the cylinder and the crankcase changes the ring pack dynamics, which results in higher oil consumption. Oil consumption was measured using a sulfur tracer technique. Careful design is required to achieve the best tradeoff between reductions in unburned hydrocarbon emissions and oil control.

scholarly journals Experimental Study of Lube Oil Characteristics in the PCV System and Effects on Engine Oil Consumption

2004 ◽  
Author(s):  
Oscar Lopez ◽  
Tian Tian ◽  
Victor W. Wong
Keyword(s):  
Strong Relationship ◽  
Spark Ignition Engine ◽  
Engine Oil ◽  
Outlet Temperature ◽  
Oil Consumption ◽  
Crankcase Ventilation ◽  
Air Intake ◽  
Oil Characteristics ◽  
Ring Pack ◽  
The Impact

Engine oil consumption is an important source of hydrocarbon and particulate emissions in modern automobile engines. Great efforts are being made in recent years to minimize the impact of oil consumption on engine emissions. Research engineers continue to study the sources and driving mechanisms of oil consumption. Of these mechanisms, the contribution from the Positive Crankcase Ventilation (PCV) system is the least investigated. However, recent studies have shown that the blowby contribution to oil consumption could be significant under certain conditions. The PCV system refers to the system that vents the blowby gases loaded with oil back to the engine air intake system. It includes oil separators, air breather connecting the intake with the crankcase, and a flow-regulating valve. In a closed crankcase ventilation system, the oil-loaded blowby and crankcase gases are fed back into the air intake. Blowby gases are formed during engine operation by leakage of unburdened and compressed air-fuel mixture from the combustion chamber past the engine piston and ring pack into the crankcase. The oil that is circulated back into the intake through the PCV system could leave deposits in the intake manifold, and thus both the quantity and physical characteristics of the re-circulated oil are of great interest. This study analyzes the PCV blowby-oil consumption mechanisms and examines the main oil sources and oil characteristics by combining oil-consumption with in-cylinder measurements. A sulfur-tracer method was used along with a gravimetric method to measure the blowby oil consumption dependence on oil level, coolant outlet temperature, operating speed and load in a production spark ignition engine. Liquid oil distribution on the liner and piston was also studied using a Laser Induced Fluorescence (LIF) technique. In addition, in-cylinder variables such as the liner temperature and cylinder pressure that affect the oil evaporation and blowby flow rates were also measured. The blowby oil consumption map showed an increase in oil consumption with load and speed. Further analysis showed that the blowby flow was mainly dependent on the load of the engine, whereas the oil concentration in the blowby did not show this strong relationship. Whether the blowby gases pick up more oil in the ring-pack region than oil in the crankcase was thus carefully analyzed. Supplementally, a strong relationship was observed between oil consumption and sump oil level, showing that oil in the crankcase is an important source of oil in the blowby. More experiments were run at different coolant outlet temperatures to study the blowby oil consumption aimed at identifying the sources of oil in the blowby. The results show that oil evaporation is dependent on the liner temperatures that increase with load and speed. These data provided additional information to distinguish among the possible sources of blowby oil consumption. Additional experimentation was carried out to estimate drop-size distribution of oil suspended in the ventilated gases, which showed that entrainment of small oil droplets in the PCV flow varied with both speed and load.

scholarly journals An OpenFOAM simulation of the natural ventilation system in a university chemical laboratory

2020 ◽  
Vol 167 ◽  
pp. 04003
Author(s):  
M Córdova-Suárez ◽  
O. Tene-Salazar ◽  
F. Tigre-Ortega ◽  
S. Carrillo-Ríos ◽  
D. Córdova-Suárez ◽  
...  
Keyword(s):  
Working Conditions ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Operating Conditions ◽  
Climate Data ◽  
Chemical Laboratory ◽  
Indoor Airflow ◽  
Air Intake ◽  
Air Speed ◽  
Closed Environment

The indoor airflow with a natural ventilation system was numerically calculated using the laminar and turbulent approach. In the chemical laboratory of the Technical University of Ambato, the computational code OpenFoam demonstrated an ability to numerically predict flow patterns. The design contemplated the natural ventilation system considering the laboratories’ working conditions not only in summer, but also in a winter week. These two operating conditions are calculated on a fully open and closed environment. For a room with a capacity of 20 people, the climate data average values were recorded at 14.0 ° C, 81.7%, 1.7 m /s for temperature, relative humidity, and wind speed, respectively. Furthermore, the demonstration has shown that the homogeneous occupancy air speed average is was 0.7 m / s with a facade air intake of 1.0 m / s 0.6 m / s in the room valid for the exchange of air and evacuation of pollutants. The maximum pressures were found in the lower part of the laboratory. This prevents the modification of the thermo-hygrometric conditions.

scholarly journals Innovative HVAC System Using an Integrated Greenhouse for a Virtual Low Energy Office Building

2019 ◽  
Vol 111 ◽  
pp. 04011
Author(s):  
Catalin Lungu ◽  
Florin Baltaretu
Keyword(s):  
Natural Ventilation ◽  
Energy Use ◽  
Ventilation System ◽  
Office Building ◽  
Treatment Unit ◽  
Heating And Cooling ◽  
Venturi Effect ◽  
Innovative System ◽  
Air Intake ◽  
Air Humidification

In this paper the authors describe a HVAC innovative system using an integrated greenhouse for heating and cooling an office building. The ventilation system allows natural (night) or mechanical ventilation and the passive cooling during the summer, including cold storage in the building structure and the PCM plywood and the refrigeration energy use during the day. Natural ventilation occurs when the wind or the Venturi effect, created by the « hat » that supports the photovoltaic panels, is strong enough; otherwise, a variable speed exhaust fan mounted on top of the building is used. The plants inside the greenhouse can produce O2 under certain conditions necessary for refreshing the ventilation air. The environment of the greenhouse allows air humidification naturally, without the use of humidifiers. If the greenhouse is sufficiently insulated in winter, it can be used in the ventilation process: the air intake from offices through the greenhouse, humidified and enriched in O2 (premixed, if necessary, with fresh air) reaches the general air treatment unit, and then sent back. The process is similar in the summer, but without recirculation, due to the humidity of the air extracted from offices. Stale air humidification enhances the thermal transfer process from the desiccant collector.

scholarly journals Oxygen Distribution and Air Leakage Law in Gob of Working Face of U+L Ventilation System

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Xiaowei Zhai ◽  
Bo Wang ◽  
Shangrong Jiang ◽  
Weixia Zhang
Keyword(s):  
Oxygen Concentration ◽  
Spontaneous Combustion ◽  
Ventilation System ◽  
Burial Depth ◽  
Air Leakage ◽  
Coal Spontaneous Combustion ◽  
Working Face ◽  
Air Intake ◽  
And Control ◽  
The Relationship

In order to prevent and control coal spontaneous combustion effectively in the gob of U+L working face, the 30105 working face of Hanglaiwan mine was taken as the research object. The relationship models between oxygen concentration and burial depth of the two tunnels in the gob of U+L working face were established. The distribution of oxygen in the gob of the working face of U+L ventilation system was studied by field observation combined with numerical simulation. The results show that the air leakage in the gob is serious. There are a number of fluctuation areas where the oxygen concentration first decreases and then increases in the air intake side of the gob. The oxygen concentration peaked at 100m, 175m, and 245m, respectively, from the intake side of the gob. In the same position of the gob depth, the air leakage intensity on the intake side is generally higher than that on the return side, and the oxygen concentration on the intake side of the gob is slower than the return side. Oxygen concentration maintains at 5.09% when the depth of gob reaches 400m. Measures to prevent coal spontaneous combustion should be strengthened in the air intake side.

An experimental investigation of the oil film distribution in an oil–gas cyclone separator

2016 ◽  
Vol 231 (1) ◽  
pp. 14-25 ◽  
Author(s):  
Lingzi Wang ◽  
Jianmei Feng ◽  
Shijing Xu ◽  
Xiang Gao ◽  
Xueyuan Peng
Keyword(s):  
Flow Pattern ◽  
Pressure Loss ◽  
Film Flow ◽  
Separation Efficiency ◽  
Flow Behavior ◽  
Outer Cylinder ◽  
Cylinder Wall ◽  
Cyclone Separator ◽  
Oil Film ◽  
Oil Gas

The film flow behavior in an oil–gas cyclone separator was experimentally studied to improve the separation efficiency in terms of the effect of the oil film on the cylinder wall. The oil film flow pattern was captured using a high-speed camera, and the cylinder wall was divided into seven regions to analyze according to the different oil film flow patterns. Along the cyclone cylinder height, the central part of the cylinder was the main flow area, in which droplet–wall collisions and oil film splashing were severe. Additionally, the oil film’s distribution characteristics under inlet velocities of 14.0, 16.0, and 18.0 m/s were compared, and the results showed that more splashing oil droplets were generated under higher inlet velocity. Moreover, changing the structure of the central channel and outer cylinder slightly changed the oil film’s area and flow pattern but exhibited a weak effect on the oil film thickness and re-entrainment. Then, an improved structure was proposed by adding a porous cylinder to the outer cyclone to avoid the generation of small splashing droplets from the oil film. The performance of the modified separator was measured in a real oil-injected compressor system, which demonstrated higher separation efficiency with no increase in static pressure loss. The separation efficiency increased by up to 2.7%, while the pressure loss decreased by up to 10%. Thus, the improved structure can improve the performance of oil–gas separators by changing the distribution and thickness of the oil film on the cylinder wall.

Physical activity in modern society: is there also an environmental benefit?

2006 ◽  
Vol 33 (2) ◽  
pp. 87-88 ◽  
Author(s):  
JULES PRETTY
Keyword(s):  
Physical Activity ◽  
Fossil Fuels ◽  
Modern Society ◽  
Motor Vehicles ◽  
Health Costs ◽  
Oil Consumption ◽  
Environmental Benefit ◽  
Potential Health ◽  
The Usa ◽  
Environmental Savings

Higgins (2005) has shown that increased human physical activity in the USA could lead to both improvements in physical health and reductions in oil consumption by motor vehicles, thereby also reducing carbon emissions. It is an intriguing idea and, as the health costs of obesity are so high, the potential health and environmental savings could be vast. These questions deserve wider attention, as all the trends suggest that consumption of both fossil fuels and food calories (combined with more sedentary lifestyles) will continue to rise in the coming years.

Highly effective oil mist separator for crankcase ventilation

MTZ worldwide ◽  
2003 ◽  
Vol 64 (3) ◽  
pp. 6-8 ◽  
Author(s):  
Hartmut Sauter ◽  
Kay Brodesser ◽  
Dieter Brüggemann
Keyword(s):  
Crankcase Ventilation ◽  
Highly Effective ◽  
Oil Mist

scholarly journals Narrow Opening

2002 ◽  
Vol 124 (03) ◽  
pp. 58-59 ◽  
Keyword(s):  
Fluid Dynamics ◽  
Ventilation System ◽  
Homogeneous Distribution ◽  
Droplet Dispersion ◽  
Water Separation ◽  
Flow Problems ◽  
Visualization Software ◽  
Air Intake ◽  
The Difference ◽  
Narrow Opening

This article discusses about a requirement that aims to protect occupants from dangerous smoke concentrations and keep escape routes clear in a building that houses a restaurant in Zurich, Switzerland. It has to be ventilated with windows in the roof that open automatically in case of fire. For a substantial building, the difference between automated venting for one percent and two percent of a roof surface can represent tens of thousands of dollars. The AFC Air Flow Consulting hired by the restaurant uses computational fluid dynamics and visualization software to improve construction and product design before too much time or money is committed. The company has provided solutions for flow problems ranging from cold downdraft along facades to droplet dispersion. A field of growing interest for AFC is industrial engineering. The company optimizes the airflow to accommodate various parameters in technical parts, such as the airflow in a medical inhaler for homogeneous distribution of droplets, or the air intake device of a car ventilation system for water separation.

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