ZANCHINI , E.

The thermal design of a nearly zero energy one-family house, in North-Centre Italy, is described. The house has a timber frame, a wood-fiber thermal insulation for the roof and a wood-fiber plus YTONG blocks thermal insulation for the lateral walls. Forced ventilation with high efficiency heat recovery is employed. Heating and cooling is...

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A new method for the hourly simulation of fields of long BHEs (borehole heat exchangers) is presented, in dimensionless form. The method considers also the internal structure of the BHE, with reference to double U-tube BHEs. The analytical expressions of new g-functions (time evolutions of the dimensionless temperature, averaged along the BHE...

The long-term time evolution of the mean surface temperature of the most critical BHE, for BHE fields with arbitrarily given monthly heat loads and no groundwater flow, is studied by means of finite-element computations performed through COMSOL Multiphysics and the superposition of effects. A unit step heat load, with duration of one month, is...

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The fully developed laminar mixed convection in a vertical circular duct is studied analytically, with reference to non-axisymmetric boundary conditions such that the fluid temperature does not change along the axial direction. The Boussinesq approximation is applied by taking the average temperature in a duct section as the reference fluid...

The 2D heat transfer from offshore, completely buried pipelines is studied with reference to transient working conditions. In particular, the start-up case is considered (i.e., the case of a pipeline initially at equilibrium with the surrounding soil). Two different start-up cases are investigated: the step-rising case and the smooth-rising...

The steady-periodic heat transfer between offshore buried pipelines for the transport of hydrocarbons and their environment is investigated. This heat transfer regime occurs for shallow water buried pipelines, as a consequence of the temperature changes of the seabed during the year. First, the unsteady two dimensional conduction problem is...

In the framework of the EU-funded Project HERB (Holistic Energy-efficient Retrofitting of residential Buildings), the University of Bologna and the Municipality of Bologna are performing the energy retrofitting of a detached house with 6 apartments in Bologna. The annual saving of primary energy obtained by the retrofitting will be assessed...