2. Benchmark solution#

2.1. Calculation method#

We start from the energy equation [éq 3.1.3-1] from document [R7.01.11], which in this case gives:

_images/Object_3.svg

eq 2.1-1

In which

_images/Object_4.svg

denotes the enthalpy of water,

_images/Object_5.svg

its mass flow,

_images/Object_6.svg

the mass intake of water and

_images/Object_7.svg

heat flow.

Given the assumptions made, it is easy to see that:

_images/Object_8.svg

Eq 2.1-2

_images/Object_9.svg

Eq 2.1-3

_images/Object_10.svg

Eq 2.1-4

_images/Object_11.svg

Eq 2.1-5

_images/Object_12.svg

is the thermal diffusion coefficient,

_images/Object_13.svg

is the hydraulic diffusion coefficient,

_images/Object_14.svg

intrinsic permeability,

_images/Object_15.svg

,

_images/Object_16.svg

,

_images/Object_17.svg

are respectively the density, the viscosity and the calorific heat at constant pressure of water.

By reporting [éq 2.1-2], [éq 2.1-3], [éq 2.1-4], and [éq 2.1-5] in [éq 2.1-1] we find:

_images/Object_18.svg

eq 2.1-6

We ask:

_images/10000370000069D500002EB71819ED95FDC94958.svg

and

_images/Object_19.svg

We get

_images/Object_20.svg

eq 2.1-7

2.2. Benchmark results#

In order to obtain the steady state more quickly, coefficients such as:

_images/Object_21.svg

The solution for [éq 2.1-7] is then:

_images/Object_22.svg