Answer / subhasish

We need to recall the joule thompson effect.
The Joule-Thomson coeffcient JT is defned as derivative of
the temperature T with respect to the pressure p at
constant enthalpy h.

coeff = (dT/dP) at const h

The curve is an inverted U shaped type and when the slope
i.e. co-eff is +ve then temp of gas increases with increase
in pressure and this is true for LPG also (Boiling point~-
38 degC at 1 atm pressure). It implies, LPG can be
liquefied by increasing pressure as the dew point also
increase. That's why even at room temp, by increasing
pressure LPG can be liquefied.

what is isothermal process?

1 Answers   Coromandel,

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DIFFERENTIAL EQUATIONS - EXAMPLE 20.2 : During the landing process of an airplane, the velocity is constant at v. (a) If the displacement of the plane is x at time t, find the differential equation that relates t, x and v. (b) The plane has 2 parts of wheels - the front and the back, separated by a distance L. The front part of the wheel touches the land first, that allows the straight body of the plane to form an angle T with the horizontal land. If the vertical distance between the back part of the wheel and the horizontal land is y, find the equation of y as a function of L and T. (c) Find the differential equation that relates dy as a function of dt, v and sin T. (d) Find the differential equation that consist of dy as a function of y, L, v and dt. (e) Find the equation of y as a function of v, L, t and C where C is a constant. (f) When t = 0, prove that y = exp C as the initial value of y.

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While there, are many tests available to detect leaks on vessels, is there a technology available to quantify the leak, or measure the flow through a leak?

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Why cavitation is produced

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Question 75 - The molecular weights M in kg / mol of 3 different monomers a, b and c in a polymer are Ma = 14, Mb = 16 and Mc = 18. The fraction of polymer chain X of 3 different monomers a, b and c in a polymer are Xa = 0.5, Xb = 0.3 and Xc = 0.2. (i) Calculate number average molecular weight by using the formula Ma Xa + Mb Xb + Mc Xc. (ii) Calculate weight average molecular weight by using the formula (Ma Xa Ma + Mb Xb Mb + Mc Xc Mc) / (Ma Xa + Mb Xb + Mc Xc). (iii) Calculate the polydispersity by using the answer in (ii) divided by answer in (i). (iv) If the molecular weight of repeat unit is 12, calculate the degree of polymerization by using the formula (Ma Xa + Mb Xb + Mc Xc) / (molecular weight of repeat unit).

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how to convert Nm3/hr to Kg/hr for air, @ 10.4 kg/cm2.g dischare pressure, does density doesn't affect on calculation?

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When using a pumping loop to mix two miscible fluids in a tank, when can the content are considered well mixed?

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Explain what are the design considerations for a piping system for the transfer of slurries?

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What is the ignition temp. of Alluminium,Coper&Iron.

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Is there a quick rule-of-thumb to estimate a gas side heat-transfer rate inside the tubes of a shell and tube heat exchanger?

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ACCOUNTING AND FINANCIAL ENGINEERING - EXAMPLE 34.34 : A biochemical engineering company has stock P = 20,000 shares of M % preferred stock of Q = $100 par and N number of shares of $20 par common stock. In year 1 : $10,000 is distributed as dividend. In year 2 : $25,000 is distributed as dividend. Let (Total Dividend) = (Dividend for Preferred Stock) + (Dividend for Common Stock). (a) In year 1, calculate the amount distributed as dividend for preferred stock, when no dividend was distributed for common stock. (b) In year 2, the amount distributed for common stock was $5000. Find the values of M and N, when the dividend per share for common stock is $0.05.

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ENVIRONMENTAL ENGINEERING - QUESTION 22.2 : Biochemical Oxygen Demand (BOD) could be calculated using the formula BOD = (DOi - DOf) (Vb / Vs) where Vb = Volume of bottle in ml, Vs = Volume of sample in ml, DOi = Initial dissolved oxygen in mg / L, DOf = Final dissolved oxygen in mg / L. (a) By using a bottle of Vb = 300 ml with sample Vs = 30 ml, find the BOD if DOi = 8.8 mg / L and DOf = 5.9 mg / L. (b) By using a bottle Vb = 600 mL with sample Vs = 100 mL, find the BOD if DOi = 8.8 mg / L and DOf = 4.2 mg / L. (c) Find the average BOD = [ Answer of (a) + Answer of (b) ] / 2. (d) If the BOD-5 test for (a) - (c) is run on a secondary effluent using a nitrification inhibitor, find the nitrogenous BOD (NBOD) = TBOD - CBOD. Let TBOD = 45 mg / L and CBOD = Answer of (c).

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