Recent content by nebousuke

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    How to determine the darcy friction factor for irregular cross section ducts

    I am not the familiar with weymouth and panhandle. Would the colebrook equation or swamee and Jain estimate the friction factor for gas flow adequately acurate? Speaking of which, would the estimation of minor losses, mainly the K value differ between liquid and gas as well?
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    How to determine the darcy friction factor for irregular cross section ducts

    I've heard something about swiss SIA standard... SIA 197, but I can't find much information about it. Anyone got a copy of it and saw something I've mentioned in it?
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    How to determine the darcy friction factor for irregular cross section ducts

    yeah... you are right.. I've mistaken the concept. If it's turbulent I believe the literature of analysis would be different. I wonder the D in swamee jain or colebroke for that matter means hydraulic diameter or just diameter because I've only work on those equations on circular pipes and on...
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    How to determine the darcy friction factor for irregular cross section ducts

    Ah geez, thanks almost forgot about that fact. My boss asked me to look up for some Swiss standards for tunnels. I found something called SIA 197, Projecting of tunnels, Basic, I wonder anyone heard of it? It's in German and I don't really read Germans so anyone can tell me what is it about...
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    How to determine the darcy friction factor for irregular cross section ducts

    I am assuming laminar flow since the medium is air, though I haven't done the calculations yet as I wasn't given the air flow requirement yet so I just assumed laminar first. I've checked with one book of mine, McGraw Hill, it did list out different equations for different cross section...
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    How to determine the darcy friction factor for irregular cross section ducts

    The problem with the f=64/re solution is that it is limited to circular pipes. but the cross section of the tunnels are neither circular, square nor rectangular. Thus it made the f = 64/re relation invalid
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    How to determine the darcy friction factor for irregular cross section ducts

    How to determine the darcy friction factor for irregular cross section tunnels hi, I needed to calculate the f value for tunnels with these cross section area but I am not sure what are method available to calculate these shapes. Two of those cross section areas are already provided as...
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    Minor loss due to Sudden contraction (help needed)

    I had... i made 2 more points further down with an increment of 1 cm of from each point. Are you suggesting it is due to vena contractra? But won't it be that the region at vena contractra contribute more pressure drop than after the flow fully developped? Are you suggesting that I should...
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    Minor loss due to Sudden contraction (help needed)

    My experiment is based on water by the way. It was to investigate how eccentricity affects minor loss due to sudden contraction. I built a concentric setup as control. Well, I have been thinking of using a simple U-shape manometer but I don't seem to be able to find a suitable mano fluid...
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    Minor loss due to Sudden contraction (help needed)

    Thanks, no wonder I've never seen it. Anyway, still it didn't explain the difference between theoretical values and experimental results. I would have expected increment in pressure loss in experimental results but it came out as the other way round.
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    Minor loss due to Sudden contraction (help needed)

    So what you mean is that the K I found through Crane's, the V, I should use is with respect to the velocity of the larger diameter pipe? h_L=K_L\frac{V^2}{2g} In that case value I found for h_L is 0.065m, Some difference between the one I calculated using the chart, which is 0.071m. By the...
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    Minor loss due to Sudden contraction (help needed)

    Sorry for sounding a bit ignorant but I am not very familiar with the part about calculating the K for sudden contraction.
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    Minor loss due to Sudden contraction (help needed)

    My set up is build to study sudden contraction not gradual contraction, the chart in the book is also for sudden contraction. I have include an attachment of the chart I used.
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    Minor loss due to Sudden contraction (help needed)

    Hi, I am an undergraduate, doing an experiment regarding of minor losses due to sudden contraction. However, I found that my theoretical loss is higher than the experimental loss. The flow rate = 3.28*10^-4 (m^3/s) (Inner diameter) D1= 3.652*10^-2 m (Inner diameter) D2= 1.539*10^-2 m by...
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