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Venturimeter vs Orificemeter, loss of energy, cost and uncalibrated accuracy.


So what are the differences between Venturimeter and Orificemeter, in terms of loss of energy, cost and their uncalibrated/ un-calibrated accuracies. Let's find out.

Instrument Loss of EnergyInitial CostAccuracy variation with calibration (uncalibrated accuracy)VenturiVenturi Meter minimizes the form friction and therefore less energy
loss. About 90% is recovered.Initial cost is higher.They are more accurate than the orifice meter, because they are generally less affected by temperature and corrosion etc. Their discharge coefficient varies with Reynold's number and
variations may be 0.5- 1.5%OrificeDue to the form friction, a large amount of energy is lost and
unrecovered. Only 60-70% is recovered.They are in-expensive, because it is just a thin plate with orifice.There are many factors including the sharpness of edges, corrosion, temperature pressure etc. which affect the performance of orifice. If all combined the inaccuracy may range up to 10%. So they are less accurate…
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Laminar flow between two parallel plates (Navier-Stokes Equation)


When the fully laminar fluid flow is developed between two parallel plates along the x-direction, the Navier-Stokes equation is applied and can be written and solved for the fluid velocity u as shown in the images below.


Energy line and Hydraulic Grade Line


Energy Line

Energy line represents the the sum of the Pressure Head, velocity and elevation Head corresponding to an assumed datum.
If there are no losses in a system, Energy head remains constant.

Hydraulic Grade Line

Hydraulic Grade line represents the Energy head subtracted by the velocity head. In other words it represents the sum of the pressure head and the elevation head along a system of fluid flow.

Example: If an Venturimeter is attached to a pipe connected to a vessel at the bottom, the Hydraulic grade changes significantly. See the image below, calculations are also given.

Water Resources and System Engineering (CE- 6003)- B.Tech. 6th sem

Please find herewith the Question Paper of Water Resources and System Engineering(CE-6003), set by HPU/HPTU (Himachal Pradesh University/ Himachal Pradesh Technical University) for the year 2014.

B.Tech. 6th Semester Examination Water Resources and System Engineering CE-6003 Time: 3 Hours                                                                               Max Marks: 100 The candidate shall limit their answers precisely within the answer-book(40 pages) issued to them and no supplementary continuation sheet will be issued.

Note: Attempt five questions selecting one question from each sections A,B,C and D. Question 9 is compulsory, All questions carry equal marks. Non- programmable calculator is allowed.
Section - A
1. (a) Describe the functional requirements of various users in a multipurpose water-resources project. What is the compatibility of these users in the …

Ten major Dam reservoirs of India- safety storage of India


 This article mentions the names of the dams in the water resources map of India.

These are the major dams which form the reservoirs that are the major water resources of India.

Bhakra Dam - in Himachal PradeshIt forms the third largest reservoir named as Gobind Sagar, with a storage capacity of 9.34 km^3. With an height of 226m, Bhakra dam is the highest vertical concrete gravity dam in Asia. 

It is constructed just on the border of Himachal and Punjab, on the Sutlej river in the Bilaspur district of Himachal Pradesh.  2. Tehri Dam  in Uttarakhand

 With a height of 261m its the highest dam in India. It's an rock and earth fill dam, constructed on the Bhagirathi river near Tehri in Uttarakhand. Reservoir has a capacity of 4.0 Km^3.
3. Sardar Sarovar (Gujrat)With an installed reservoir capacity of 9.5 Km^3, it is one of the largest reservoir.

Length of the dam is 1.21 Km, while the height is 128 m and growing. 
4. Rihand Dam (Uttar Pradesh)Witha a length of 934 m and a height of 91 m,…

GATE 2014, PSUs- irrigation Engineering - one liners - part 11

Hello there,

Here is the 11th part of our notes for the preparation of the GATE and PSUs exams.

Fertility of a soil is adversely affected, when the pH value is more than 11.Optimum depth of kor watering for rice crop is nearly 19 cm.Average delta of rice crop is nearly 120 cm.The duty of a crop is 432 hectares/cumec, when base period of the crop is 100 days. Delta for the crop will be 200.Water consumed in irrigation, when compared with the total water used for all purposes in our country, is about 90%.Water consumed for producing one tonne of wheat and one tonne of rice will be of order 2000 tonnes and 4000 tonnes.Lime concrete lining is used when velocity of flow is below 2 m/sec, irrigation channel with capacity upto 200 cumec and where economy is required.Thickness of concrete lining, for discharge upto 200 cumec varies from 10 to 15 cm.Force considered for the analysis of an elementary profile of a gravity dam under empty reservoir condition is self weight.Uplift pressure on a da…

Comparison of Kennedy's and Lacey's Theories


Here is a brief comparison of Kennedy's theory and Lacey's theory for the design of channels for canal etc.

The concept of silt transportation is same in both the cases, both agree that the silt is carried by the vertical eddies generated due to friction of the flowing water against rough surface of canal. Kennedy considered a trapezoidal channel section and, therefore, he neglected eddies generated from the sides. For this reason, Kennedy's critical velocity formula was derived only in terms of depth of flow(y).  Lacey considered that an irrigation channel achieves a cup-shaped section(semi-ellipse) and that entire wetted perimeter of the channel contributes to the generation of silt supporting eddies. He, thus, used hydraulic mean radius(R) as a variable in his regime velocity formulas instead of depth(y).Kennedy stated all the channels to be in state of regime provided they did not silt or scour. But Lacey differentiated between two regime conditions, i.e. initia…