code: def chung(target, Cv='pore.heat_capacity',
            acentric_factor='pore.acentric_factor',
            mol_weight='pore.molecular_weight',
            viscosity='pore.viscosity',
            temperature='pore.temperature',
            critical_temperature='pore.critical_temperature'):
      r
      Cv = target[Cv]
      acentric = target[acentric_factor]
      MW = target[mol_weight]
      R = 8.314
      T = target[temperature]
      mu = target[viscosity]
      Tc = target[critical_temperature]
      Tr = T/Tc
      z = 2.0 + 10.5*Tr**2
      beta = 0.7862 - 0.7109*acentric + 1.3168*acentric**2
      alpha = Cv/R - 3/2
      s = 1 + alpha*((0.215+0.28288*alpha-1.061*beta+0.26665*z) /
                     (0.6366+beta*z+1.061*alpha*beta))
      value = 3.75*s*(mu)*R/(MW)
      return value
docs: r"""
      Uses Chung et al. model to estimate thermal conductivity for gases with
      low pressure(<10 bar) from first principles at conditions of interest
  
      Parameters
      ----------
      target : OpenPNM Object
          The object for which these values are being calculated.  This
          controls the length of the calculated array, and also provides
          access to other necessary thermofluid properties.
  
      acentric_factor : string
          Dictionary key containing the acentric factor of the component
  
      Cv : string
          Dictionary key containing the heat capacity at constant volume
          (J/(mol.K))
  
      mol_weight : string
          Dictionary key containing the molecular weight of the component
          (kg/mol)
  
      viscosity : string
          The dictionary key containing the viscosity values (Pa.s)
  
      temperature : string
          The dictionary key containing the temperature values (K)
  
      critical_temperatre: string
          The dictionary key containing the critical temperature values (K)