Recent content by gezibash

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    Enthelpy for Constant Pressure and Constant Volume Systems?

    Well before I answer this we must be very careful in this assumption $$\text{d}S=0$$ Many physical systems such as turbines, compressors and pumps are very well insulated therefore it is possible to consider any heat transfer negligible and ultimately they may be modeled as isentropic. However...
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    Enthelpy for Constant Pressure and Constant Volume Systems?

    Use the following logic, $$ \text{d}H = \delta\text{Q} + v\,\text{d}P $$ knowing that, $$ \text{d}S = \frac{\delta\text{Q}}{T} $$ rearrange to get the Gibbs relation $$ \text{d}H = T\text{d}S+ v\,\text{d}P $$ Assume boldly $$\text{d}S=0$$ And you get reversibly adiabatic shaft work. $$ \text{d}H...
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    How to Plot a Thermodynamic Cycle in T-s Diagram?

    Homework Statement I have been given a description of a thermodynamic cycle that looks like this. I have two polytropic processes (n1=1.2, n2=1.9), and one isochoric. The known data are: p1 = 1 bar T1 = 15 °C p2 = 15 bar Homework Equations p v^(1.2) = 0.7958 p v^(1.9) = 0.69657 The Attempt...
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    Designing a Car Engine Piston: Thermodynamics Question

    Lol I could not have been wronger than my previous post. I used the combined mass of both the fuel and air. Clearly that is not a fuel consumption rate. I need to use m_1\approx 0.15 \text{gm}
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    Designing a Car Engine Piston: Thermodynamics Question

    Yeah, but I would have to time the cylinder stroke. Check my train of thought here, n_1\;m_1\;N_c = \dot{m} Where n_1 = 1500\;\text{rpm}, m_1 = 2.448\;\text{gm} and N_c = 8 (number of cylinders).
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    Designing a Car Engine Piston: Thermodynamics Question

    Yes, that seems pretty good. I was just making sure that the answer itself is logical, so anything around 2-3 grams would be on the right track here.
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    Designing a Car Engine Piston: Thermodynamics Question

    Hi Chet, thanks for the reply. Sadly I did not manually calculate the densities, I used Tables from the internet to get them at 20°C, 1 bar - since I figured those would be intake conditions.
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    Schools Can I Access University Libraries Without Being a Student?

    To be honest I did not think much of the problems associated with me witholding my location. The question I asked would be a valid question even if I was a US citizen since my interest was to know if it is possible to subscribe, using my own financial resources, to an online library (most likely...
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    Schools Can I Access University Libraries Without Being a Student?

    I did not think that it would matter that much. It's not like I am requesting access to confidential information. Apart from that, if some library has a policy that it only serves citizens of a specific country I'm sure they would request some identification like the Social Security number or...
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    Schools Can I Access University Libraries Without Being a Student?

    I have, and no they don't have access. I have tried pretty much everything from my end. I've even tried the National Library. No luck.
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    Schools Can I Access University Libraries Without Being a Student?

    Well, yes I would do that - but things get weirder. I live in a 3rd world country, and this is the only university that offers an engineering program. Studying abroad was a possibility for me about two years ago when I first enrolled, but by now it's a bit late since I would have to repeat...
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    Schools Can I Access University Libraries Without Being a Student?

    Thanks for the reply. Yes I suppose this is a controversial topic, but I am not just interested on open access. Something commercial as well would be suitable as long as it is within a certain range. Kind of like a subscription on a regular library, a monthly/annual charge and then I would be...
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    Schools Can I Access University Libraries Without Being a Student?

    I study on a university that, let's just say does not have much resources for us students. So I need to get access to some online libraries such as Springer Books, Elsevier, Knovel etc. I have been using a friend's credentials, he studies on a prestigious university and they have access to the...
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    Physics help? Topic: kinetic energy?

    Please show your work first, and then we will be able to guide you.
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    Comsol Mechanical Thermal Contact

    Will you explain what do you have to do with the model? Could you provide some diagram or something where you got the problem from? As far as I can see you're trying to compute a multiphysics problem here. I can see you are trying to create a temperature difference and then there's also a...
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