Heat to work conversion during upward heat convection Part I: Carnot engine method

Abstract The heat to work conversion efficiency during upward heat convection is shown to be an order of magnitude larger than the generally accepted value. The work produced when heat is carried upward by convection is roughly equal to the upward heat flux multiplied by the Carnot efficiency calculated using the average temperatures at which heat is received and given up. The work calculated using the enthalpy equation is shown to be equivalent to CAPE and to the reduction in the total enthalpy of the system. The enthalpy equation is more direct than CAPE because there is no need to consider buoyancy at intermediate levels. The work is fully determined by the initial and final conditions of the air mass which is moved. The enthalpy equation is also more direct than the reduction in the enthalpy of the system because there is no need to know the total enthalpy of the system. The work is shown to be roughly independent of whether the heat is transported upward as sensible or as latent heat and of the mass flux used to transport the heat. A novel method of calculating reversible and irreversible expansion temperatures is described.