Recent content by steve2510

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    Spring damper system equation of motion

    Well as the energy is lost the amplitude decreases starting off at a maximum I guess, so there must be a time where the amount of energy lost means the amplitude falls below 2mm, i mean if I multiply both sides by 3.18 I get that 3.18 x energy lost per cycle = energy stored, at first I thought...
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    Solving Stress Concentrator Homework: Plate with Hole in Center

    Homework Statement A plate with a hole in the centre is loaded in tension It has a height of 86mm (W), a thickness of 12 mm, a hole diameter of 33mm and a yield stress of 346MPa. The tensile load is 117kN. A) Determine the stress on the top edge of the hole B)Determine the stress on the top...
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    Designing a Twin Screw Pump - Why the Pressure Loss?

    I'm having to design a screw pump and I'm a bit confused about things, I've never really seen a screw pump before. I've decided upon a twin screw - screw pump and my first question is why do most examples have an outlet at a higher level than the input, surely that just leads to a pressure loss...
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    Error Calculation for Triangular Plate Sides

    oo what a silly mistake \frac{\partial a}{\partial A} = \frac{160*125*sin(\frac{pi}{3})}{\sqrt{125^{2}+160^{2} - 2bccos(\frac{pi}{3})}} = \frac{17320.51}{145.688} \frac{\partial a}{\partial A} = 118.888 \frac{\partial a}{\partial A} * δA = 2.075 2.075 + 0.1545 + 0.335 = δa δa = 2.56 → 2.6...
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    Error Calculation for Triangular Plate Sides

    δa = \frac{\partial a}{\partial b} δb + \frac{\partial a}{\partial c} δc + \frac{\partial a}{\partial A} *δA δb = 0.5 δc = 0.5 δA = pi/180 \frac{\partial a}{\partial b} = \frac{b-cCos(A)}{\sqrt{b^{2}+c^{2} - 2bccos(A)}} \frac{\partial a}{\partial b} =...
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    Error Calculation for Triangular Plate Sides

    Nope completely forgot about that, thanks Well that leaves me with [(125*250*2*sin(pi/3) / 291.4 ] *pi/180 = 3.24 which is still off, i can't see where I've made a mistake, I've done problems after this one and been fine, i just can't seem to get this one.
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    Error Calculation for Triangular Plate Sides

    My answers are Partial b = [((2b-2cCosA)/2*(b^2+c^2-2bcCos(A))^1/2] *δb = [((250 - 160)/2*((125^2 + 160^2 - 2*160*125*0.5)^0.5))] * 0.5 = (90/291.4) * 0.5 = +-0.154 partial c has the same denominator [((2c - 2bcos(A)) / 291.4) ]*0.5 = 195/291.4 * 0.5 = +-0.335 Partial A has the same...
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    Error Calculation for Triangular Plate Sides

    Homework Statement Two Sides of a triangular plate are measured as 125mm and 160mm, each to the nearest millimetre. The included angle is quoted as 60+-1. Calculate the length of the remaining side and the maximum possible error in this result My first question is to the nearest millimetre...
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    MATLAB Solving MatLab Misunderstanding: Element-by-Element and Point-wise

    [SIZE="4"][FONT="System"]I'm current learning MatLab before i start my second year of engineering and i don't really understand a fundamental aspect of it. My problem is the use of the period "." and when it is deemed to be necessary. I've looked up what this operator does and found...
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    How Does Heating Affect Pressure and Temperature in a Sealed Steam Container?

    Honestly my first instincts was to do this. Whats confused me in my teacher solution is that he's said the specific volume of the initial condition(where there is a dryness fraction) will be constant through the whole process as it goes from 8 bar and to 10 bar. But surely the specific volume...
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    How Does Heating Affect Pressure and Temperature in a Sealed Steam Container?

    So with linear interpolation : d is the variable i want, ie pressure. g is the variable I've been given vg D1=8 bar D2=9 bar G1=0.2403 G2=0.2149 G=0.2367 8+(0.2367-0.2403/0.2149-0.2403)*(9-8) = 8.142 I don't see why the specific volume wouldn't change, surely when it...
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    How Does Heating Affect Pressure and Temperature in a Sealed Steam Container?

    Homework Statement A rigid vessel of volume 2.5 m3 contains steam at a pressure of 6 bar and a dryness fraction of 0.75. If the contents of the vessel are heated, determine: i) the pressure at which the steam becomes dry saturated, ii) the temperature of the steam when the pressure reaches...
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    Thermodynamics ( steam tables ) isentropic

    Thanks, well I'm using "Thermodynamic and Transport Properties of Fluids" So i can use the entropy of the system i guess. Am i right in saying for a isentropic process dS=0 Therefore; @ 400c, 20 bar S=7.126 @ 16KPA Sf= 0.772 Sfg= 7.213 So 7.126 = 0.772 + x7.213 X= 0.88 I think I'm actually okay...
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    Thermodynamics ( steam tables ) isentropic

    Hm didn't notice the large numbers, its just a past exam question so i guess its Made up. I just don't believes there's enough Information to find X, I am puzzled.
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    Thermodynamics ( steam tables ) isentropic

    Homework Statement The power output of an adiabatic steam turbine is 5 MW. If the device can be assumed to operate as a steady flow device with isentropic expansion, determine the following: i) The dryness fraction, x, at the exit from the turbine; ii) The work output per unit mass of steam...
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