Managing Electric Efficiency Essay Example

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Exhaust system


Over the years the exhaust system has been given several responsibilities and its work has expanded. Initially it was a comparatively an easy dust system designed to avert toxic and anoxic exhaust gases from go into the driver’s cab. Currently the modern diesel exhaust system minimizes noise and even provides a hand with raising a vehicle’s fuel economy, authority and in general driveability. Alterations in governmental rules and regulations also alter the customers demand. During the past thirty years, the federal state and local governments of the United States introduced noise pollution control. The federal noise control act of the year 1972 was the first worldwide law to control truck noise levels. Moreover the noise, other bi-products of engine incineration are exhaust particles plus gases released in to the exhaust system(United State environmental protection agency, 1969). Legislation to manage the levels of these emissions took place in 1988, 1990, 1991, 1994, 2004 and 2007 (Richards, 2007). Every regulatory change minimized the acceptable levels of incineration-interrelated gases which could be permitted to egress the exhaust system. Therefore to meet the emission laws, Cummins filtration works intimately with all engine and truck manufacturers to offer exhaust components. Cummins filtration as a worldwide leader in exhaust design, they developed and offered an extremely expertise fleet guard exhaust systems which, minimizes noise and reduces hurtful gases (Richards, 2007).

The exhaust systems which are shabby or insufficient are the major and the mainly recurrent contributors to lofty noise level. Ocular scrutiny plus repair of leaking relations or substitute of unsuccessful components will obviously minimize noise levels, if the noise is till lofty the addition of resonators, packed stacks or adjustment in mufflers is recommended.

An exhaust system is typically tubing employed to direct reaction exhaust gases away from a managed incineration in an engine. The whole system transmits burnt gases from the engine plus includes one or more exhaust tubes, depending on the whole system design. Therefore the exhaust system should be well designed to lug toxic and noxious gases way from the users of the machine. Enclosed generators plus furnaces can rapidly fill a covered space with carbon monoxide or any other poisonous exhaust gases if there are not well vented to the outdoor. Again, the gases from most machines are extremely hot, and therefore the pipe should be heat-resistance. The chimney works as an exhaust pipe in a motionless structure on the other hand, for the internal incineration engine it is vital to have the exhaust system “Turned” this is referred as a turned pipe for optimal efficiency and it should meet the regulation norms maintained in each country, for instance, in European countries Euro 5, India BS-4.

The components of the exhaust system include the following; manifold, manifold pipe and connector, exhaust pipes and elbows, muffler, stack pipes or tail spout, clamps, and resonators. The manifold is the main components of the exhaust system; it is made of cast iron that collects all the exhaust as it comes out of the head in to a single collector, then it delivers the burned gases into exhaust pipes.

The exhaust pipes and elbows are used to hold the exhaust and direct it to the rear of the vehicle as fast and resourcefully as possible. They are also used to make an efficiently preserved pathway to guide the exhaust gas carefully from the engine to the exterior of the trailer. Exhaust pipes are made in various sizes and shapes, though there are mainly two kinds; regular and flexible pipes. The exhaust system may be potted by welding joints; then again instead of welding exhaust clamps can be used in situate of welding as an easy and effectual means to fasten overlapping pipes. The method of fastening the system is a personal reference of the proprietor or fleet manger. There are also requests where resonators are used to start to diminish the noise prior to it reaches the muffler. The muffler is used to minimize noise made by the engine during incineration as sound emission enters the muffler chamber they are broken up and the noise dispels.

The total quality construction of heavy duty, medium duty and most current light duty exhaust products are manufactured by Cummins filtration (Bethea, 2008). This is the largest OEM suppliers of the exhaust systems and leader in engine exhaust noise technology. They are well recognized as the most reliable manufacturer since they can be counted for quality along with consistent of quiet operations, low back pressure and fuel effectiveness. The Cummins filtration offers firm’s prized products under its fleet guard brand, the fleet guard are designed for sturdiness and convention turned to meet present noise level rules and regulations. The fleet guard still provides an economy muffler which, goes together with the competition, featuring heavier gauge flanges as well as internal flanges support. This gives the customer confidence on using the products from fleet guard since they act for the interest of the public as a whole, thus the most preferred by the most firms.


Pressure drop due to frictional losses in the duct = Pressure loss per meter (Pa/m) x the number or equivalent number of meters of duct

Friction pressure losses in pipes or duct represent the energy loss due to friction of the fluid in a pipe of constant section. They are expressed in heights of fluid (in meters) and pascals

H = λ L VManaging Electric EfficiencyD2

DH is the friction pressure losses in pipes or duct in heights of fluid (in meters column of fluid Mcf or Mcw if water)

V = the average speed flow meters in seconds

D = the diameter’s flow meters

L= the length of the flow meters

l = loss coefficient of friction (unitless number)

Determining the coefficient of pressure loss from the flow regime

Duct 1 — 600 mm x 600 mm which operates at 3 Pa/m.

Duct 2 — 750 mm x 750 mm which operates at 1 Pa/m.

Duct 3 — 1000 mm x 1000 mm which operates at 0.25 Pa/m

Question A

The average velocity of the air to meet the required volume flow rate

Duct 1 — 600 mm x 600 mm which operates at 3 Pa/m, while the air path is 87 meters and the required volume flow rate of 5000 l/s.

Preliminary, head necessitated to conquer friction losses and to maintain velocity head is to be calculated by applying the above equation.

Q= 5000 l/s = 5 m³ /s

A= 0.6 * 0.6 = 0.36 m²

Av. Velocity = Q/A =13.88 m/s

Velocity head = V²/2g = 9.83 m of air column

The pressure a fan needs to produce to overcome the frictional losses in the duct,

Frictional head to overcome by the fan = 3*87=267 Pa

Fan pressure = 1.145 * 9.83 * 9.8 KPa + 267 Pa = 110.63 KPa

Fan power required = PQ = 110.63 * 5 = 555 Kw

B. For each duct and fan combination, present in a table the electricity cost for: i) a weekday, ii) a weekend day, ii) a week, iv) a year & v) 10 years.

Electricity cost = the total cost multiply by total kWh (kilowatt hours)

In a weekday (7am to 7 pm, 12hrs), there are two tariffs; that is peak and shoulder

Shoulder starts from 7am to 2pm

While, peak starts from 2pm to 7pm.

Shoulder = $0.12 per kWh * 6hrs = 0.72

Peak = $0.21 per kWh * 6hrs = 1.26

Total cost = 1.26 + 0.72 = 1.98

(ii) A weekend day

Shoulder = $0.14 per kWh * 12hrs = 1.68

(iii) A week

Peak = $0.21 per kWh * (12*5) = 7.2

(iv) A year = (shoulder 8days/month * $0.14 per kWh) * 12 = 13.44

(Peak 22days/ month * $0.21 per kWh) * 12 = 55.44

Total cost = 13.44 + 55.44 = 68.88

(v) 10 years

(13.44 * 10) + (55.44 * 10) = 688.8


Bethea, R. M. “Air Pollution Control Technology”. New York: Pearson prentice print 2008.

Richards, J. R. “Control of Particulate Emissions new jersey”: sage print 2007

United States:” Environmental Protection Agency”. 1969. “Control Techniques for

Particulate Air Pollutants”.