# Search results

1. ### Control systems -- input with non-zero initial conditions

1. Homework Statement Deriving an s-domain equation for the following inputs a) &b) 3. The Attempt at a Solution I understand how to derive the equation for an input with zero initial conditions (part a) but I'm not sure what to do when there are non-zero initial conditions (part b)
2. ### Composite lay-up

1. Homework Statement a)Describe a potential laminate lay-up that would exhibit high shear stiffness b)Describe a potential laminate lay-up that would exhibit a low poissons ratio 3. The Attempt at a Solution a) is a unidirectional lay-up in the direction of the shear force best? b) an evenly...
3. ### Radial/Hoop stress in a steel turbine disc

1. Homework Statement 2. Homework Equations -given in question 3. The Attempt at a Solution I am bit confused with the boundary conditions of this problem. I understand the radial stress is zero on the inside diameter and the radial stress on the outside diameter will be the reaction to...
4. ### Material selection for vehicle leaf spring

1. Homework Statement I've gone though a material selection process to pick the optimum material for a rear leaf spring suspension for a vehicle (~700mm long) and I've selected the top 10 materials based on fatigue, fracture, toughness, cost, yield etc: -Stainless steel, martensitic, AISI...
5. ### Material selection based on either U1 or U2 merit index

1. Homework Statement Choose a component based on either U1 or U2 merit index and select what you believe to be the optimum material. 2. Homework Equations U1=(σ)^2/E (Energy density) U2=(σ)^2/(Eρ) (specific energy density) 3. The Attempt at a Solution I was going to use a spring damper...
6. ### Von Mises stress

If the von mises stress well is below the yield stress, am I right to assure the material is behaving elastically?
7. ### Picking an element type for FEA

When choosing between a 2D 4-node quadrilateral element and 8-node for FEA stress analysis, why is the 8 node option preferred? I understand it has much more flexibility with different shapes due to the central mid node but are there any other reasons?
8. ### Proximity Sensor, Design Project

I've taken a year out of university to work at a design company and they have given me a project to design/make a test rig which measures the position of a metal shaft within an actuator assembly to check if its within a +/- 0.2mm tolerance. Some of the key requirements are: No contact with...
9. ### Thermal Resistance

1. Homework Statement Explain how the concept of thermal resistance can be used in the analysis of heat transfer problems 2. The attempt at a solution So I'm made a few key points but I am not sure if I have answered the question fully: Thermal resistance is a heat property and a...
10. ### Surface temperature of a tile

Hi, I have written a matlab program to calculate the surface temperature on a tile and I am trying to find the most stable/accurate differenceing technique. I have plotted the surface temperature (where its actual value is ~122.5) against the time step for the differencing techniques shown...
11. ### Flat-pack coffee cup

Hi, I am a 2nd year student studying Mechanical Engineering. As part of our design module we are doing a feasibility analysis into a 'disposable Fold-flat cup with an integrated lid' which is to replace existing coffee cups. I understand their are some patents for similar products which would...
12. ### Heat transfer across an infinite plate of constant thickness

When modelling the heat transfer through a plate using fouriers equation, what difference would it make if the width and length of the plate were set to a specified value rather than being infinite?

1. Homework Statement A circular floor 9.15 m in diameter has an emissivity of 0.8 and is at a temperature of 29.4C. The floor is enclosed by a hemispherical metal dome which has an emissivity of 0.1. If the net rate of heat transfer between the floor and the dome is 660 W, calculate the...
14. ### MATLAB MATLAB, NASAs thermal protection system

Hi, I am writing program to model the heat flow through different space shuttle tiles. I have got it working using four different methods: Forward differencing, Backward differencing, Crank-Nicolson, DuFort-Frankel and all four methods give me similar results. What are the advantages and...
15. ### Space shuttle thermal protection tiles

Hi, I am writing a MATLAB program to model the heat flow through space shuttle tiles. Does anyone know where I can find the thermal conductivity, density and specific heat of the different tiles on a space shuttle?
16. ### Steam Motor Efficiency

I am doing an experiment to determine the performance of a steam plant cycle and analyse it in comparison with the ideal rankine cycle. I have a sketch of the actual and real T-S diagram for the steam plant (See attached) I am unsure what factors cause the change in the shape of the T-S...
17. ### Secondary phase, heat treatment

"Precipitation hardening is a heat treatment that distributes secondary phases more evenly in an alloy..." What does it mean by a secondary phase?