Current vs Static Electricity Can you imagine a world without TVs, computers, cell phones, cars, and the light bulb? Electricity is an amazing thing. It is such a wide field of study, and many people are still confused by it.
Static electricity is generated by liquids flowing through pipes, and in mixing, pouring, pumping, filtering, or agitating liquids. The rate of generation is influenced by the conductive of the liquids, the amount of turbulence in the liquid, the interfacial surface area between the liquids and other surfaces, liquid velocity, and the presence of impurities.
Some specific locations where static electricity is generated include: Piping Systems - In piping systems the generation rate and the subsequent accumulation of static charge are a function of the flow rate, liquid velocity, pipe diameter, and pipe length. Filling Operations - The turbulence experienced in filling operations, caused by large flow rates, splashing or free-falling liquids, greatly increases the charge accumulation above the level generated in piping systems.
Filtration - Filters, because of their large surface area, can generate as much as times the electrostatic charge generated in the same piping system without filtration. Dispersing Operations - Of all operations in the coatings industry, dispersing operations can be particularly hazardous in view of the extremely high rate of charge generation when particulates are present.
With poorly-conductive liquids the charge accumulation can cause hazardous sparking in the vapor space, such as to an exposed agitator blade in a mixer or to a conductive fill pipe.
High charge generation rates can also occur when liquids are mixed, thinned, tinted or agitated. Methods of Static Control In addition to being dependent on the charge generation rate, charge accumulation is a function of the resistance of the path by which charges dissipate.
Some flammable liquids have very low conductivities and tend to accumulate static charges. Toluol, an example of such liquid, has a long history of causing fires. Piping Systems - The most effective method of reducing the accumulation of static charges in piping systems is through proper pipe sizing to keep liquid velocities low.
A recommended maximum velocity in piping systems is 15 feet per second. Filling Operations - Splash filling and free-fall of flammable liquids should be eliminated to the maximum extent practical by lowering fill velocities, by providing diverters to direct the discharge of liquid down the side of the grounded vessel being filled, or by submerging fill pipes below the liquid level in the vessel.
Submerging of fill pipes in paint manufacturing vessels may not always be practical. In bulk-filling operations the velocity of the incoming liquid should not exceed 3 feet per second until the pipeoutlet is covered; the velocity may then be increased to the 15 feet per second maximum mentioned previously.
Table II also lists the flow rates for various pipe size for the velocity of 3 feet per second. Filtration - Experience has shown that this hazard maybe controlled by installing filters far enough upstream of discharge points to provide a 30 second liquid relaxation time prior to discharge.
The required relaxation time depends upon the conductivity, the liquid velocity, and the type of filter. For example, the 30 second relaxation time may not be necessary with a conductive liquid. Dispersing Operations - For dispersing operations, the conductivity of the liquid should be raised1, if necessary, to above conductivity units C.
If possible, polar solvents should be added before non-polar solvents or particulates are added. Polar solvents are more conductive than non-polar solvents. In some instances, proprietary anti-static agents, developed for use with fuels, can be used as additives to reduce the charge accumulation.
Typically, only a few parts per million of the additive are required. Tests should be run to ensure that the conductivity additive does not cause formulation problems.Static and dynamic analysis: basic concepts and examples Ragnar Nymoen Department of Economics, UiO 18 August Formal dynamic analysis in economics is a relatively new (A graph of a dynamic multiplier from a static model) 0 5 10 15 20 We will consider important software vulnerabilities and attacks that exploit them -- such as buffer overflows, SQL injection, and session hijacking -- and we will consider defenses that prevent or mitigate these attacks, including advanced testing and program analysis techniques.
What Is a Static Force? A static force refers to a constant force applied to a stationary object. A static force is too weak to move an object because it is being countered by equally strong opposite forces. The most common example of a static force is static friction on a stationary object.
If an. An Introduction and an Analysis of the Static Electricity PAGES 2. WORDS View Full Essay. More essays like this: static electricity, electrons, current, flow of electrons.
Not sure what I'd do without @Kibin - Alfredo Alvarez, student @ Miami University. Exactly what I needed. - Jenna Kraig, student @ UCLA. Static Analysis based on the program AST There are a number of different strategies for detecting problems in code before it runs.
One technique that is relatively simple and quite powerful is based on analyzing the program AST looking for problematic patterns and rejecting such programs. Aug 26, · In this lecture I introduce the use of static analysis for malware identification.