I have got differential pressure from an inclined manometer to be 2.8kPa and density of the fluid is 784kg/m^3. I need to calculate the manometer datum height. how do i do tht?? thnx for the help in advance.
There is an article about inclined manometer datum height at
http://books.google.com/books?id=zLwtngK3T1UC&pg=PA52&lpg=PA52&dq=manometer+datum+height&source=bl&ots=Ue8TuGDwNQ&sig=3cx6cTfh0dM9ke9UWC7uxW6OHrY&hl=en&ei=FywBTJePA4HGlQeGoK3yCQ&sa=X&oi=book_result&ct=result&resnum=6&ved=0CCUQ6AEwBQ#v=onepage&q=manometer%20datum%20height&f=false
It seems you need an area ratio for the two colums of fluid that the manometer uses. read the article and see how you can use it to predict datum height d.
Look for Figs 3.3 and 3.4 on page 53 of the reference cited above. The area ratio is only needed on the Fig. 3.3 version.
It seems to me they are asking the problem backwards: you already know the pressure difference and are asked to solve for some column height difference.
yes i used the ame formula but didn't get the correct ans. cn u help me solve it. i want ans to be 6.5 inch (0.165 meters).
To calculate the manometer datum height, you need to use the equation:
P = rho * g * h
Where:
P is the differential pressure (2.8 kPa in your case),
rho is the density of the fluid (784 kg/m^3 in your case),
g is the acceleration due to gravity (approximated as 9.81 m/s^2 in most cases),
h is the manometer datum height (the value we are trying to find).
Rearranging the equation to solve for h, we have:
h = P / (rho * g)
Now, we can substitute the values into the equation:
h = 2.8 kPa / (784 kg/m^3 * 9.81 m/s^2)
Note: To ensure consistent units, you need to convert kPa to Pa by multiplying it by 1000.
h = (2.8 kPa * 1000 Pa/kPa) / (784 kg/m^3 * 9.81 m/s^2)
Simplifying:
h ≈ 0.357 m
So, the manometer datum height is approximately 0.357 meters.