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Piping, Plumbing Abbreviation

As isometric piping drawing become denser in information and crowded with compound, the piping engineer start to use piping abbreviations in the design work to reduce the space requirement of the callout of the fitting or in the note section of the mechanical piping drawing.   The list below includes most of the piping abbreviation used in the piping drawings, plumbing abbreviation, Plumbing fittings abbreviations, steam piping abbreviation, flow diagram, piping arrangement drawing, isometric…  Each engineering companies or operating companies have their own abbreviation list that should be used for a specific drawing or a specific situation.  I did my best…

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Dimensionless Numbers in Heat Transfer

Biot number (Bi) The Biot number, Bi is dimensionless, which is ratio between of the internal and external resistance. where h is the average heat Transfer coeficient. L length dimention, The ratio between the volume and the surface area. k thermal conductivity. Drag coefficient (Cf) The drag coefficient is the ratio of surface shear stress and the free-stream kinetic energy Eckert number (Ec) Eckert number (Ec) define he relationship between a flow’s kinetic energy of flow and the boundary layer enthalpy difference. This dimensionless number is used to characterize heat transfer dissipation. Fourier number (Fo) Fourier number (Fo) is a…

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Prandtl Number of Water

Prandtl number of water Pr = μ cp / k Where:  cp : specific heat, (SI units: J/kg·K). μ : dynamic viscosity, (SI units: Pa s = N s/m2).   k : thermal conductivity, (SI units: W/m·K). The specific Heat, dynamic viscosity and the thermal conductivity required for the calculation of Prandtl number of the water were calculated based on the equations defined on the IAPWS-IF97. These equations have a range of validity for further details please refer to IAPWS-IF97 or to International Steam Tables – Properties of Water and Steam Based on the Industrial Formulation IAPWS-IF97. The cp,  ,μ and k were…

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Prandtl Number Of Nitrogen

Prandtl Number Of Nitrogen Table Prandtl number of nitrogen at different pressure @ 1 bar: Property values generated from NIST Database 23: REFPROP Version 7.0 (August 2002). Prandtl Number Of Nitrogen Figure More about Prandtl Number : Prandtl Number Calculator. Pandtl number of Air NITROGEN PRODUCTION FROM AIR Prandtl Number of Oil Prandtl Number Of Water

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Prandtl Number of Air

The prandtl number of air is around 0.7 as many other gases at 1 atm.The Prandtl Number is a dimensionless number approaching the proportion of momentum diffusivity and thermal diffusivity.Prandtl number equation is defined as: where:ν is the kinematic viscosity, ν = μ / ρ. μ is dynamic viscosity, (SI units: Pa s = N s/m2). ρ is density, (SI units: kg/m3).α is the thermal diffusivity, α = k / (ρ cp). k is thermal conductivity, (SI units: W/m·K) cp is specific heat, (SI units: J/kg·K) ρ is density, (SI units: kg/m3).The values of μ, cp and k are acknowledged…

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Different Types of Refrigerants

In the last decade the manufacturer developed different types of refrigerants.  The mechanical vapor compression cycle utilizes the evaporation of a refrigerant to absorb the heat, which will lead to lower the temperature of the surrounding of the evaporator. The first refrigerant used in the word was Ether in 1834 when Perkins proposed a hand operated compressor machine and in 1856 Linde developed a machine working on ammonia.  The pace of development was slow until 1930, engineer had only toxic or flammable refrigerants to choose from for their system. Sulphur dioxide, methyl chloride or isobutane used until a new refrigerant…