Recent content by nate9519

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    Why are sharp contours stress concentrators?

    intuitively it makes sense but what is the scientific explanation
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    Exploring Creative CAD Ideas: From Brake Calipers to 3D Printers

    yea something similar to that. something smaller with less parts would be ideal
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    Exploring Creative CAD Ideas: From Brake Calipers to 3D Printers

    Not really sure. I remember my teacher saying a previous student did a birdhouse. So when I say it has to be a mechanical part I am not saying that's a requirement, its just that I would rather model a mechanical part since I am going for a bsme. The only requirements are it has to be 5-8 parts...
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    Exploring Creative CAD Ideas: From Brake Calipers to 3D Printers

    This is our final project for the class. We do simple modeling for homework like bearing blocks and gaskets but this is the first assembly.
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    Exploring Creative CAD Ideas: From Brake Calipers to 3D Printers

    I have a cad project where i have to make an assembly of a mechanical device with 5-8 parts and I also have to make a modification to the device. I was thinking maybe a brake caliper but I am just curious what some of you think would be a good device to model?
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    Thermal efficiency of reciprocating engines

    In a perfect, ideal world with constant specific heats the thermal efficiency of an otto cycle is dependent on its pressure ratio and a diesel cycle is dependent on its pressure ratio and cut off ratio. But since in the real world the equations with these terms do not hold since specific heats...
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    Confusion about 2nd law of thermo

    Entropy has units of kJ/kg K and energy has units of kJ. So my question is if entropy is not conserved how is energy conserved when there is a unit of energy within entropy?
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    Thermodynamics phase change question

    My thermo teacher was talking about 2 phase rankine cycles and he said the once water boils at atmospheric pressure its temperature can not get higher than 212 no matter how much heat you add. He said the only way you can raise the temperature of steam past 212 F is the raise the pressure. Why...
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    Help with mass flow rate of turbine?

    Homework Statement An turbine expands air at 1300 kPa and 500oC to 100 kPa and 127oC. Air enters the turbine through a 0.2-m2 opening with an average velocity of 50 m/s, and exhausts through a 1-m2 opening. Determine (a) the mass flow rate of air through the turbine Homework Equations PV=RT m...
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    Why Does MATLAB Show NaN for Truss Deflections?

    Homework Statement I'm using MATLAB to design a truss and the output is suppose to be the deflections caused by the applied loads. But I keep getting "not a number" for my deflections . here is the warnings I get. Warning: System may be partially constrained. > In truss3 (line 222) In...
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    Help with thermodynamics -- work of Carnot engine expansion

    yes and that would give you an answer in kilojoules per unit mass. But the problem stated that the working fluid was 15kg of air so if I multiplied delta u by 15kg to get the answer in kJ that would be correct as well, right?
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    Help with thermodynamics -- work of Carnot engine expansion

    sorry for confusion. No I didn't mean the entire cycle is adiabatic. I meant from 2-3. My book uses a piston cylinder to demonstrate the carnot cycle and since that is a closed system I thought the first law reduces to mass*(change in internal energy) for the work from 2-3
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    Help with thermodynamics -- work of Carnot engine expansion

    Homework Statement I don't need help solving I just need some clarification. Since the carnot cycle is adiabatic, the first law would reduce to work= mass*(change in internal energy). On my test I was asked to calculate the work of the isentropic expansion of a carnot engine with air...
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    Building a truss with matlab -- Need help

    Homework Statement I am suppose to build a truss using a MATLAB code given to me. I have to identify the joint coordinates, member assembly, and load matrix. The code is suppose to calculate the deflections like fea. I have put everything in but when the code runs my deflections are "NaN" which...
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