Method and device for determining the heat loss coefficient of a premises

Patent metadata

Field	Value
Publication number	US-10481019-B2
Application number	US-201415109063-A
Country	US
Kind code	B2
Filing date	Dec 29, 2014
Priority date	Dec 30, 2013
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

A method for determining a heat loss coefficient of a premises includes undertaking application of first and second heating powers, respectively, in the premises over two successive time periods, selecting for each of the first and second time periods, a time interval for which the evolution is substantially linear, determining the slope of the tangent to the curve (Tik(t))k=1 or 2 over each time interval; and deducing the value of the heat loss coefficient of the premises on the basis of the slopes.

First claim

The invention claimed is:

1. A method for reducing a value K calc of a heat loss coefficient K of a premises, comprising:
undertaking, in the premises, over two successive time periods D 1 and D 2 :
i. over the first time period D 1 , an application of a first heating power P 1 of the premises, a campaign of measurements of at least one temperature inside the premises T i1 at closely-spaced time intervals, and a determination of the temperature of an outside air T e1 at closely-spaced time intervals, the first heating power P 1 being such that a parameter

α
=

1
-

Δ
⁢

⁢

T
1

⁡

(
0
)

⁢

K
ref

P

1
⁢

 is less than or equal to 0.8 with ΔT 1 (0)=T i1 (t=0)−T em , where t=0 is a starting point of the first time period D 1 , T em is an average temperature of the outside air over all of the time periods D 1 and D 2 and K ref is a reference value of a heat loss coefficient K of the premises, and then
ii. over the second time period D 2 , the application of a substantially zero second heating power P 2 of the premises, the campaign of measurements of at least one temperature inside the premises T i2 at closely-spaced time intervals, and the determination of the temperature of the outside air T e2 at closely-spaced time intervals;

selecting for each of the first and second time periods D 1 and D 2 , a time interval Δt 1 or Δt 2 for which an evolution T i1 (t) or T i2 (t) is substantially linear, where the time intervals Δt 1 and Δt 2 are such that the time interval Δt 1 extends up to an end of the first period D 1 of application of the first heating power P 1 and such that, when the starting points of the first period D 1 and of the second period D 2 are superimposed, the time intervals Δt 1 and Δt 2 have a same end point;
determining a slope a 1 or a 2 of a tangent to a curve (T ik (t)) k=1 or 2 over each time interval Δt 1 or Δt 2 ;
determining the value K calc of the heat loss coefficient K of the premises based on the slopes a 1 and a 2 ;
controlling the error in the value K calc of the heat loss coefficient K of the premises by controlling the parameter α less than or equal to 0.8; and
reducing the value K calc of the heat loss coefficient K of the premises based on the controlled error, the value K calc of the heat loss coefficient K of the premises being greater than or equal to 80% of the heat loss coefficient K of the premises and less than or equal to 120% of the heat loss coefficient K of the premises.

2. The method as claimed in claim 1 , wherein the time intervals Δt 1 and Δt 2 have a same duration.

3. The method as claimed in claim 1 , wherein the first time period D 1 , over which the first heating power P 1 is applied, has a duration of less than or equal to 4 hours.

4. The method as claimed in claim 1 , wherein the first heating power P 1 is such that the parameter

α
=

1
-

Δ
⁢

⁢

T
1

⁡

(
0
)

⁢

K
ref

P

1
⁢

is less than or equal to 0.75.

5. The method as claimed in claim 1 , wherein the first heating power P 1 is such that the parameter

α
=

1
-

Δ
⁢

⁢

T
1

⁡

(
0
)

⁢

K
ref

P

1
⁢

is less than or equal to 0.7.

6. The method as claimed in claim 1 , wherein the first heating power P 1 is such that the parameter

α
=

1
-

Δ
⁢

⁢

T
1

⁡

(
0
)

⁢

K
ref

P

1
⁢

is greater than or equal to 0.25.

7. The method as claimed in claim 1 , subsequent to the determination of the value K calc of the heat loss coefficient K of the premises based on the slopes a l and a 2 , the method further comprising:
computing and verifying a value of the parameter

Assignees

• Saint Gobain Isover

Inventors

• Pandraud Guillaume
• Alzetto Florent

Classifications

• G06F17/10

  Complex mathematical operations {(function generation by table look-up G06F1/03; evaluation of elementary functions by calculation G06F7/544)} · CPC title

• G01K17/20 Primary

  across a radiating surface, combined with ascertainment of the heat-transmission coefficient · CPC title

• F24D10/00

  District heating systems · CPC title