Register

Homework Help Question and Answers

Submit a new Query

Recent Homework Help Question & Answers


Question 33431

posted 1 years ago

Preliminary Design of Londiani Dam Hydropower Plant. Assuming the Londiani Dam will provide sufficient water year round. Use the map provided and determine:
1) The head (the vertical drop between your intake point and the turbine location for power generation)
2) Flow speed (how much water comes down the pipe)
3) Pipeline (penstock) length and diameter

View answer

Question 30726

posted 1 years ago

1. (20 points) An above ground swimming pool of 30 ft diameter and 5 ft depth is to befilled form a garden hose (smooth interior) of 100 ft length and 5/8 inch diameter(ID). If the pressure at the faucet outlet to which the hose is attached remains at 55psi, how long will it take to fill the pool? The water exits the hose as a free jet 6 feetabove the faucet. If water costs $8 per 1000 gallons, how much will it cost to fill thepool. Hint: to find friction factor f, you will need to iterate until the guessed f andcalculated v and Re converge on the curve for smooth pip on the moody diagram(the lowest line on the curve). Assume that the water is conveyed at 60°F.

View answer

Question 30728

posted 1 years ago

3. (12 points) Refer to example 4.5 on page 4-14 Chapter 4 Reading Assignments. You need to determine the unknown volumetric flow rate for each section of pipe. Change the given flow rates to the following:
You are to then determine the proper pipe size for each section of pipe based solely on flow rate considerations. When selecting pipe sizes, ensure that the velocity does not exceed 6ft/s. Use type L copper pipe. Provide a sketch and show the results in boxes on the sketch. All pipe is interior to the building.

View answer

Question 30727

posted 1 years ago

2. (20 points) Refer to the PIPING SCHEMATIC for example 4.4 on page 4-13 of the Chapter 4 Reading Assignments. The temperature of the water in all sections is100° Section AB is 148 feet long, is 1-1/4" type M copper pipe with a gate valve and has a flow rate of 20 gnm there is no entrance loss. Section CB is 176 feet long, is 2"type L copper pipe with a swing check valve (instead of the balancing valve shown)and has a flow rate of 70 gnm Section BD is 158 feet long, is 2-1/2" schedule 80threaded steel pipe with two 90° elbows, an exit and has the flow rate to be determined by the continuity equation. Remember that section BD has a straight thru tee and CB has a branch tee.
Instead of making the theoretical calculations, you are to use the equivalent length information provided in Appendix C on page C-11. In addition, use the charts on pages C-13 & -14 for copper pipe and the chart on C-16 for the steel pipe. Complete the following table to determine:
1. The head loss in each section (ft. w.c.).
2. The total system head loss and indicate if it is ABD or CBD (ft. w.c.).

View answer

Question 2528

posted 1 years ago

Part Bi. Write the Hazen- Williams equation for friction head loss, hf= ...ii. For iron pipes, what is a typical, mid range value for the friction coefficient, C Hw?iii. For constant C Hw, if the discharge is doubled, by what factor does the head loss increase?
Part Ci. Write the Manning equation for friction head loss, hf= ...ii. For iron pipes, what is a typical, mid range value for Manning's n, with units?iii. For constant n, if the discharge is doubled, by what factor does the head loss increase?
Problem 2: Comparing Three Equations for Head Loss
Compare three equations for friction head loss in pipes, assuming constant friction factors.Recall the slope of the energy grade line (EGL) is S= høL.
Part Ai. Write the Darcy-Weisbach equation for friction head loss, hf= ...ii. For iron pipes, what is a typical, midrange value for the friction coefficient, 2?iii. For constant 2, if the discharge is doubled, by what factor does the head loss increase?

View answer

Question 2530

posted 1 years ago

Problem 4: Open Channel Flow
A circular pipeline stretches 202 miles from an initial elevation of 510 ft to a final elevation of230 ft. The pipe (D = 3.0 ft) is made of concrete (A= 0.0030 ft). The open channel flow is steadyand uniform such that the pipe is half full. The fluid is water at 50° F.
Part A Sketch a cross-section of the pipe flowing half full, then calculate its hydraulic radius, Rh [ft].
Part B Calculate the discharge, Q [ft/s].

View answer

Question 2527

posted 1 years ago

Problem 1: Iteration Explained
Explain why iteration is required to solve the following classes of pipe flow problems using theDarcy-Weisbach equation (<20 words each part):
Part A Given pipe diameter D and friction head loss hf, find discharge Q.
Part B Given discharge Q and friction head loss hf, find required pipe diameter D.

View answer

Question 2529

posted 1 years ago

Problem 3: Culvert Roughness
A culvert transmits 0.45 m/s of water from the pond at left (surface elevation 123.0 m) to the pond at right (surface elevation 122.0 m). L =25 m and D = 50 cm. The flow is steady anduniform, and the pipe is completely full.
Part A Use Bernoulli's equation to calculate the friction head loss. [m]
Part C Calculate Darcy-Weisbach's friction factor 2.
Part B What is the average velocity? [m/s]
Part D Calculate Hazen-Williams's roughness coefficient CHw.
Part E Calculate Manning's n with units.

View answer

Question 2531

posted 1 years ago

Problem 5: Pipe Flow
This semester we worked through several versions of the pipe flow problem sketched above, in which a 3.0 ft diameter pipe is used to convey water from reservoir A (surface elevation 80 ft) to reservoir D (surface elevation 90 ft). In week 14, we considered a specific example with a cast iron pipe (A = 0.00085 ft), flow rate of Q = 40 ft/s, and average velocity of V = 5.66 ft/s. For these conditions, the friction factor was 2= 0.015 and the pump added 85 ft of head. Assume the water temperature is always 60°F.
Part A Assuming the pump is 75% efficient and electricity costs 10¢/kW hr, how much will it cost to run this pumpfor a year? Hint, 1 kW hr = (1000 watts)(1 hr) =(1000 J/s)(3600 s) = 3.6x10° J.
Part BNow let us assume we need to double the discharge to Q=80 ft’/s, but unlike the example in week 13, we are not going to make the false assumption that the friction factor 1 is constant. You may, however, assume that the roughness height A is constant. We will consider three options:
Option #1: Build a parallel system with the same pipe and pump, with a flow rate of Q= 40 ft’/sin each system. What is the annual electricity cost?
Option #2: Use the original pipe but double the velocity. What is the annual electricity cost?
Part C Briefly comment on the pros and cons of options 1-3 (<30 words).
Option #3: Build a new pipe with diameter of 50.9 in. The cross-sectional area of this pipe is twice that of a 36 in pipe, so the velocity will be V= 5.66 ft/s for a discharge of Q= 80 ft’/s.What is the annual electricity cost?

View answer

Question 1465

posted 1 years ago

Consider the water tank shown to the right.Suppose that the water depth is h 4.22 m above the ground.What is the force (in N) that is needed to hold the left wall in place? The tank is 10.33 m wide. The density of water is 1000 kg/m³ and gravity is 9.81 m/s³.(Note that hinge also exerts a force which you do not need to compute).

View answer

Questions not Found

Most popular subject

Thermodynamics

Essay/Summary

Mechanics

Complex Analysis

Engineering Economics

Calculus

Modern Physics

General Chemistry

Strength Of Materials

Fluid Mechanics

x