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    Mass flow in Vapor Compression Cylce HELP

    Hi guys, I'm doing some calculations on a vapor compression cycle system for my Master Thesis. My question is: Does the mass flow change when the refrigerant flows through the (electronic) expansion valve (assuming steady state flow)? I assume that it doesn't but I can't seem to get...
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    Calculate Specific Heat Capacity HELP

    Hi sorry for late answer. It's not an assignment it's a part of my Master Thesis. Thermodynamics is not my best field and that's why I posted this question. I need to calculate the specific heat capacity for refirgerant R-134a in three different phases; gas-phase, two-phase and liquid-phase. I...
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    Calculate Specific Heat Capacity HELP

    Calculate Specific Heat Capacity HELP!!! Hi guys, I having big troubles with how to calculate the specific heat (cp) for refrigerant r134a i gas phase. I think that assuming ideal gas behavior is a bad idea since this is going to be used in a actual system... I have values of entropy...
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    Calculate refrigerant temp inside evaporator based on exit temp and pressure

    Hi guys, I'm stuck on some thermodynamic calculations and I would really appreciate some help! I'm trying to calculate the refrigerant temperature inside of an evaporator (two-phase lumped parameter model) based on the exit temperature of the evaporator and the pressure. I've understood that...
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    Steady-state HELP

    Steady-state HELP!! Hi guys, I really need some help with this! I have this set of equations for an evaporator which I want to calculate x0 and u0 for the steady state mdotin(hin - hg) + (B1/Ltot)*L1(Tw1 - Tr1) = 0 mdotout(hg - hout) + (B2/Ltot)*L2(Tw2 - Tr2) = 0 mdotin - mdotout = 0 B3(Ta -...
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    Isentropic Specific Enthalpy HELP

    Hi guys, I'm struggling with some equations regarding the enthalpy change over a compressor in a vcc system. I'm currently working on a model for the whole system and I think I've got all equations except the one describing the enthalpy difference betweeen the inlet and outlet of the...