Lesson 4 - Water (Civil Engineering)

WATER ENGR. DONN PEDRO T. PANGANIBAN ✓ Understand the definition, properties, and characteristics of water ✓ Name and explain basic properties of fluid flow ✓ Solve engineering problems involving the properties and flow of water What is Water is the name given to the 212 °𝐹 𝑜𝑟...

WATER ENGR. DONN PEDRO T. PANGANIBAN ✓ Understand the definition, properties, and characteristics of water ✓ Name and explain basic properties of fluid flow ✓ Solve engineering problems involving the properties and flow of water What is Water is the name given to the 212 °𝐹 𝑜𝑟 100 °𝐶 liquid compound 𝑯𝟐 𝑶. It is a colorless, transparent, odorless liquid that forms the seas, lakes, rivers, and rain and is the basis 32 °𝐹 𝑜𝑟 0 °𝐶 of the fluids of living organisms. under standard atmospheric pressure (𝟏𝟒. 𝟔𝟗𝟔 𝒑𝒔𝒊 = 𝟏𝟎𝟏. 𝟑𝟐𝟓 𝒌𝑷𝒂) Did you know? The temperature at which water boils decreases with lower atmospheric or system pressure and increases at higher pressures. Thus, the temperature at which water boils decreases with elevation increase.  (𝝆) ✓ the degree of compactness of a substance 𝑔 ✓ larger density = more compact 𝜌𝐻2𝑂 = 1000 ✓ amount of mass in a given volume 𝐿 𝑔 𝜌𝐻2𝑂 = 1 𝑐𝑚3 𝑘𝑔 𝑚 𝜌𝐻2𝑂 = 1000 3 𝑚 𝜌= 𝑉 𝑠𝑙𝑢𝑔𝑠 𝜌𝐻2𝑂 = 1.94 𝑓𝑡 3  (𝜸) ✓ amount of weight in a given volume ✓ parang density lang pero weight naman yung icoconsider! 𝑊 𝑘𝑁 𝛾𝐻2𝑂 = 9.81 3 𝛾= 𝑚 𝑉 𝑙𝑏 𝛾 = 𝜌𝑔 𝛾𝐻2𝑂 = 62.4 3 𝑓𝑡  (𝑺𝑮) ✓ a dimensionless quantity that is defined as the ratio of the density or unit weight of a substance to the density or unit weight of water at a specified temperature and pressure 𝜌 𝑆𝐺 = 𝜌𝐻2 𝑂 𝛾 𝑆𝐺𝐻2𝑂 = 1 𝑆𝐺 = 𝛾𝐻2 𝑂  (𝑽) ✓ the amount of space occupied by a substance 𝑖𝑛3 𝑓𝑡 3 1 𝑚3 = 1000 𝐿 𝑚3 𝐿 1 𝑐𝑚3 = 1 𝑚𝐿 1 𝑓𝑡 3 = 7.48 𝑔𝑎𝑙 1 𝑔𝑎𝑙 ≈ 3.8 𝐿 Calculate the specific weight, density, and specific gravity of 1 liter of petrol which weighs 7 N. A 500 L of Emperador Light weighs 396.942 kg. Calculate the density and specific gravity. Calculate the specific weight, density, and specific gravity of oil having a volume of 4.5 m³ and weighs 40 kN.  (𝑷) ✓ the force per unit area exerted by a liquid or gas on a surface such as the sidewall of a container or pipe 𝐹 𝑙𝑏 𝑖𝑛2 𝑜𝑟 𝑝𝑠𝑖 𝑃= 𝑙𝑏 𝑜𝑟 𝑝𝑠𝑓 𝐴 𝑓𝑡 2 𝑁 𝑜𝑟 𝑃𝑎 𝑚2  (𝑷) (𝑃𝑎𝑡𝑚 ) is the pressure on the earth’s surface 𝑃𝑎𝑏𝑠 = 𝑃𝑎𝑡𝑚 + 𝑃𝑔𝑎𝑢𝑔𝑒 (𝑃𝑎𝑏𝑠 ) is the pressure of a fluid (gas or liquid) Standard 𝑷𝒂𝒕𝒎 : including pressure exerted by the atmosphere 1 𝑎𝑡𝑚 = 101325 𝑃𝑎 (𝑃𝑔𝑎𝑢𝑔𝑒 ) = 760 𝑚𝑚 𝐻𝑔 is the pressure of a fluid (gas or liquid) = 760 𝑇𝑜𝑟𝑟 excluding pressure exerted by the atmosphere  (𝑷) STATIC PRESSURE RESIDUAL PRESSURE DISCHARGE PRESSURE At sea level, atmospheric pressure is 14.7 psi (101325 Pa). A pressure gauge placed at the bottom of an 8 ft (2.45 m) deep tank filled with water measures a water pressure at the tank bottom of 3.5 psi (24130 Pa). Determine the absolute and gauge pressure. At sea level, atmospheric pressure is 14.7 psi (101325 Pa). A bicycle tire (at sea level) is inflated to 50 psi (344737 Pa). Determine the gauge and absolute pressures in the inflated tire. In Denver, atmospheric pressure is about 11.8 psi (81358 Pa). A bicycle tire (in Denver) is inflated to 50 psi (344737 Pa). Determine the gauge and absolute pressures in the inflated tire in mmHg.  (𝑸) ✓ the volume of a substance that passes a point in a system per unit of time 𝐿 𝐿 𝑚3 𝑓𝑡 3 𝑓𝑡 3 𝑔𝑎𝑙 𝑔𝑎𝑙 ✓ , , , 𝑐𝑓𝑠 𝑜𝑟 , 𝑐𝑓𝑚 𝑜𝑟 , 𝑔𝑝𝑠 𝑜𝑟 , 𝑔𝑝𝑚 𝑜𝑟 𝑠 𝑚𝑖𝑛 𝑠 𝑠 𝑚𝑖𝑛 𝑠 𝑚𝑖𝑛 𝑽: Volume of fluid 𝑉 𝒕: Time 𝑄= 𝑄 = 𝐴𝑣 𝑨: Cross-sectional area 𝑡 𝒗: Velocity of flow A pipe has a diameter of 230 mm and the water flows at a velocity of 8 m/s. Determine the volumetric flow rate in liters per second. A 15L tank with a 150 mm diameter hole at the bottom. It takes 8 minutes to drain the water from full to empty. a) Find the average volumetric flow rate of water b) Determine the average velocity of water as it exits the hole Determine the gauge pressure and absolute pressure 7 meters below a swimming pool. A sample of gas with a total pressure of 570 kPa contains 35% Argon. Determine the partial pressure of the argon gas in kPa. Raw sewage is found to weigh 60.5 pounds per cubic foot. Determine its specific gravity. a) Determine the volumetric flow rate, in L/s, for water flowing out of a faucet based on 2 gal in 23 seconds b) Determine the volumetric flow rate, in gpm, for water flowing out of a faucet based on 6 L in 8 seconds Determine the average velocity in feet per second for water flow in a pipe under the following conditions: a) A 3⁄4-in diameter, Type L copper tube (0.875 in outside diameter and 0.785 in inside diameter) carrying water at a volumetric flow rate of 10 gpm. b) A 2-in diameter, schedule 40 chlorinated polyvinyl chloride (CPVC) pipe (2.375 in outside diameter and 2.047 in inside diameter) carrying cold water at a volumetric flow rate of 40 gpm. Determine the average velocity (in m/s) for water flow in a 20-mm diameter copper tube (21.4 mm outside diameter and 19.9 mm inside diameter) carrying water at a volumetric flow rate of 40 L/min Thank you!