N5E43 Hydraulics - Level 4 and Level 5 Higher National Diploma Construction and The Built Environment
P1 Evaluate a hydraulic condition in order to determine the parameters of the problem .
P2 Illustrate a proposed solution to a hydraulic problem, using drawings or models
P3 Solve a Darcy-Weisback equation for a given pressure pipe system
P4 Solve a Manning's equation for given open channel flow situation.
P5 Calculate the head loss for a given pipeline
P6 Define pipe sizes for a given set of flow parameters
P7 Calculate the pressure exerted on a foundation wall in a given context
P8 Calculate the pressure exerted on a subsurface floor in a given context
M1 Compare proposed solutions to a hydraulics problem, highlighting the merits of different solutions
M2 Discuss the differences and similarities between different types of hydrodynamic systems and calculations
M3 Evaluate pipe sizes to determine the flow type that will occur
M4 Evaluate the ability of a given subsurface wall and floor to resist the forces exerted by liquid in a given context.
D1 Assess pipework sizes to determine their efficiency in a given context
D2 Present proposals for subsurface structures in response to the hydrostatic pressure of a given context .
Assignment - Hydrostatic problems and selecting suitable pipe sizes
Learning Outcome 1: Apply concepts of physics to develop solutions to hydrostatic and hydrodynamic problems
Learning Outcome 2: Calculate forces related to fluids at rest and in motion
Assignment Brief and Guidance:
Scenario
You have recently been appointed as an assistant civil engineer, working for a multi-disciplinary medium-sized practice. Your initial training period will be spent working in the hydraulics section of the company. As such you have been asked to study the concepts of physics that relate to hydrostatic and hydrodynamic problems. You have also been set a range of calculations to complete to demonstrate your understanding and knowledge.
Part A Hydrostatic Solutions
Task 1 - Explain hydrostatic pressure and identify the hydrostatic pressure formula prior to answering the following task. There is a fluid flow between two parallel plates 80mm apart. The velocities of the flow were found by direct measurement as the table below:
Plot the velocity distribution curve and determine the mean velocity of the flow and comment the flow condition and characteristics of the flow. If the fluid flow is a turbulent flow, use a diagram or model to illustrate the flow.
A vertical gate of 5m height and 3 m wide closes a tunnel running full of water. The pressure at the bottom of the gate is 195 kN/m2. Determine the total pressure on the gate and position of the centre of the pressure and the parameters of the problem using standard engineering notation. Illustrate the proposed solution using a scaled drawing.
Task 2 - The properties of a fluid have a major impact on the fluid flow conditions. Explain how the fluid properties such as density and viscosity are used to calculate the Reynolds number. How does the viscosity of a fluid impact on the boundary layer?
Explain the difference between viscous, laminar, transitional and turbulent flow and how this relates to the Reynolds number, demonstrating this link using illustrations or models.
Part B - Hydraulic Solutions Task 3
a) Determine the friction factor with Darcy-Weisback equation for water flowing through a 300mm diameter pipe with water flow rate at 0.2m3/s and 120m long pipe run under a pressure difference of 3.8m head.
b) An open channel for storm water discharge system with a cross-section of trapezium shape with a bottom width of 4m and side slopes of 1 vertical to 1.5 horizontal. Assume the roughness coefficient n is 0.025, the bed slope is 1/1800 and the depth of the water is 1.2m. Determine the volume rate with Manning formula.
Assignment 2 - Designing Subsurface Structures
Learning Outcome 3: Develop practical solutions for the distribution of fluids within correctly sized pipes
Learning Outcome 4: Calculate the hydrostatic pressure exerted on substructures for a given context.
As an assistant civil engineer, working for a medium-sized practice, you have been asked to assist in the hydraulic section with a series of calculations relating to local construction project. These will involve the calculation of pipe sizes and flow parameters for a pipe network that services a reservoir and the associated pressure on the foundations of buildings that surround the proposed dam. You will learn the skills used in predicting what types of flows and pressures will occur in a practical application of fluid and pressure engineering. This skill is valuable in been able to predict within a design context the consequences of actions before they are constructed and avoid expensive mistakes or claims from third parties. To summarise been able to ‘model' an engineering outcome saves costly mistakes later in projects when it is too late to make expensive variations to designs.
Part A: Calculations for Head Losses through pipelines
a. Water is flowing through a 40mm diameter pipe with an average velocity of 0.1m/s. You are required to identify the condition of flow and calculate the head loss of the fluid under that flow condition. Assume the density and viscosity of water are 998kg/m3 and 1.002x103 Ns/m2.
b. To control the flow to be laminar flow, what is the pipe size for the fluid flow?
c. From the results above or otherwise, evaluate the flow conditions would occur under different pipe sizes.
d. Determine and give comment the pipe sizes and the characteristic of fluid for the efficiency of the fluid flow in a pipe.
Part B: Calculations for Pressure on vertical wall
As being an engineer for a project, there is a structural element with a foundation wall and a subsurface floor at the bottom and the given groundwater level as shown in the figure below. To study the stability of the structural element, preliminary calculation will be required as follows:
a) Calculate the pressure exerting on the vertical wall.
b) Calculate the pressure exerting on the horizontal floor surface.
c) From the result of (a) & (b), calculate the force acting on the structural elements and comment on the ability of the structural element to resist the force exerted by the groundwater. Explain with proposals how the structural elements to be improved to resist the external hydrostatic pressure.
Attachment:- Hydraulics.rar