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  1. M

    Calculating LEV face velocity to hold plate in place.

    LEV needs to be at 1m/s at the face. Let’s say area of LEV is .1 m2 What size plate (with holes or not in it) and weight is needed for the plate to fall off if the face velocity is less than 1m/s but the velocity is enough to keep the plate on the lev face if the speed is 1m/s or greater. I...
  2. M

    Problem proving theory

    also its asked to prove shear strain, ill use this symbol for it. ω it asks to prove τxy (tau xy) = (E/1-v^2) [((1-v)/2) (ωxy)] given ωxy = 1/G (τxy) Any help? :(
  3. M

    Problem proving theory

    I still don't understand where the E/1-v^2 comes from.
  4. M

    Problem proving theory

    How does the first step transform into the second step. I have no idea :(
  5. M

    Help! Underfloor v radiator case study

    thanks for the reply. I'm not sure if I have the thermal resistance figs, they may be given. But, the study is comparing different types of floor. -timber floor concrete floor - no insulation concrete - 80mm insulation concrete - 250mm insulation :)
  6. M

    Help! Underfloor v radiator case study

    Homework Statement 4. ANALYSIS The Excel Data File will allow the following analysis to be conducted for both emitter types: a) Calculate the variation in both the temperature drop across the emitter ( T) and total heat emitted (Q) over the entire test period for each of the 3...
  7. M

    Using Kirchhoff's Laws to Find Currents, Source Current and Power Dissipated

    I = current and the voltage stays the same in a parallel circuit
  8. M

    How to calculate energy used in a variable speed drive

    Thanks for your reply, but I think you misunderstood. We're just running a lab experiment to show how a variable speed drive saves money. We want to run an AC pump at full throttle, then put a restriction in the pipe to reduce mass flow rate. Then we'll run the VSD at a lower speed with no...
  9. M

    How to calculate energy used in a variable speed drive

    Homework Statement We'll be running a vsd water pump. We'll be seeing the energy savings of using a vsd, instead of using an AC motor on full load and using a tap to reduce water flow. Sorry for the lack of info. The Attempt at a Solution I'm sure it will have something to do with...
  10. M

    Turbomachinery exam question

    Homework Statement No attempt done, just looking for any books or online sites that could help in solving these. They're likely to come up in my exam and am studying for other exams at the min.
  11. M

    Engineering What is mechanical engineering like?

    It's all about forces and stresses, lots of maths.
  12. M

    Engineering Engineering Physics or Mechanical Engineering

    Mechanical is quite interesting
  13. M

    Normal stress

    They're not acting along the same axis.
  14. M

    Help in designing water turbine for given wattage

    sorry, the q is in m3/hr, so it would be .0055 l^3 / second. The aim is to design the screw, work out the forces and design the thickness of the shaft etc. Maybe this is the wrong forum. The efficiency of an archimedes screw is 84%. The main aim is to design a system that aerates a...
  15. M

    Help in designing water turbine for given wattage

    Or this? This is the one I used at first but I got a veeeeery small area, for a 20m3/hr flow rate and 1.75 head difference. Would this be correct? Ph = q ρ g h / (3.6 106) (1) where Ph = power (kW) q = flow capacity (m3/h) ρ = density of fluid (kg/m3) g...
  16. M

    Help in designing water turbine for given wattage

    I found this formula "Power = Head X Flow X 7" So I can fill in the head to get a flow rate?
  17. M

    Help in designing water turbine for given wattage

    Ok, I can assume and make up heads, so assuming a head of 2m. What's next? I can assume flow rates too if need be.
  18. M

    Help in designing water turbine for given wattage

    The task is to design an archimedes screw turbine to power an 80 watt pump. I can assume flow rates, head, etc. The turbine will be at 63 degrees, so I need to find out the size of the turbine.
  19. M

    Help in designing water turbine for given wattage

    So you're saying, 9.81Sin(63) would give the energy gotten from water being flowing down a tube at 63 degrees? Or is that wrong?
  20. M

    Help in designing water turbine for given wattage

    We need to design an archimedes screw turbines to power a pump of 80 watts. Any tips to design this? I have tried a way, but I think it's very wrong. Thanks in advance :)
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