CN1721845A - Building exterior-protected construction heat transfer coefficient on-site detecting method - Google Patents

Abstract

The invention relates to an architecture exterior-protected construction heat transfer rate on-site detection method which comprises: attaching heat flow meter and temperature sensor, connecting heat flow meter, temperature sensor and temperature heat flow automatic patrol testing equipment by transmission line, attaching automatic temperature-controller with the inner wall which has heat flow meter and temperature sensor, adjusting automatic temperature-controller, automatically reading storage measuring value, computing architecture exterior-protected construction heat transfer rate. It uses differential temperature measured by temperature sensor and electromotance E outputted by heat flow meter to reflect heat flow density. It uses formula to compute heat transfer rate K.

Description

Buildings exterior-protected structure heat transfer coefficient in-situ check and test method

Technical field

The present invention relates to the detection method of buildings exterior-protected structure, especially buildings exterior-protected structure heat transfer coefficient in-situ check and test method.

Background technology

At present, China is in the period of great prosperity of construction industry development.1990-2002, the average annual growth rate of floor area of building of annual construction of China and completion is up to 155%.Along with increasing rapidly of floor area of building, people require constantly to improve to the comfort level of indoor environment.Winter, room temperature was brought up to 18 ℃-20 ℃ by 12 ℃-16 ℃; Summer, room temperature then was reduced to 22 ℃-20 ℃ by 30 ℃.It is estimated that the building energy consumption account of China society total energy consumption proportion surpasses 25% in recent years, the heating energy consumption of northern area surpasses 40% of local social total energy consumption.The greenhouse gas emissions that architectural energy consumption produces have surpassed 1/4 of national total flow rate.The immense pressure of aspects such as the energy that architectural energy consumption causes, environmental protection has caused that the Chinese government pays much attention to, and has formulated a series of buildingss and the energy-conservation standard of Architectural Equipment, with its important performance assessment criteria as the market access.Calendar year 2001, China put into effect energy-conservation field test standard " heating Residential Buildings Energy standard " (JGJ132-2001), the different regions building enclosure has been formulated heat transfer coefficient, for finally the checking on of building energy conservation work provides science, quantitative judgment basis, make more scientific, the standardization of this work., this standard working specification in the process of implementation has certain limitation, 4.47 regulations of standard " ... detection should be carried out after the normal operation of heating system ... the detection duration should not be less than 96 hours ".But actual conditions are, most construction works were completed in summer and autumn, if detect after all waiting until winter heating, the time concentrates around here, and workload is concentrated, and will inevitably bring difficulty to testing; In addition, because the restriction in season also can affect for the final acceptance of construction of engineering.

Summary of the invention

In view of the foregoing, the present invention aims to provide a kind of buildings exterior-protected structure heat transfer coefficient in-situ check and test method.This method detection method in accordance with regulations---heat flow meter method is utilized temperature automatically controlled constant temperature oven, is to cause to carry out under the environment of the temperature difference that the buildings exterior-protected structure heat transfer coefficient is on-the-spot to be detected the people, is not subjected to the restriction of time, overcomes the phenomenon of heating phase centralized detecting.

Purpose of the present invention can be achieved through the following technical solutions:

A kind of buildings exterior-protected structure heat transfer coefficient in-situ check and test method is the inside surface that heat flow meter is sticked on tested body of wall, and should contacts fully with inside surface; Temperature sensor is near heat flow meter, and the hull-skin temperature sensor sticks on the corresponding position of heat flow meter, and is evenly distributed; Adopt multiplex transmission line that heat flow meter, temperature sensor are connected with the automatic scan tester of temperature hot-fluid; Again temperature automatically controlled constant temperature oven is close to the metope that is furnished with heat flow meter, temperature sensor; Regulate temperature automatically controlled constant temperature oven, make the certain temperature difference of the inside and outside generation of tested district metope and temperature is tended towards stability; Automatically read the storage measured value, when certain hot-fluid vertical current superheat flow measuring head, produce certain electromotive force E, (C is the gauge head coefficient by formula q=CE, after gauge head is made, definite constant exactly) just can determine to flow through the heat flow density q of heat flow meter; The automatic scan tester of temperature hot-fluid writes down electromotive force E and j measured value Q of building enclosure surfaces externally and internally temperature control of heat flow meter automatically _I1Q _I2Q _I3Q _I4Q _I5Q _E1Q _E2Q _E3Q _E4Q _E5Data processing is with tested j Q _Ij, Q _Ej, q value substitution following formula:

$R=\frac{\underset{j=1}{\overset{n}{\mathrm{\Σ}}}(Q_{\mathrm{ij}}-Q_{\mathrm{ej}})}{\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{q}_j}$

Thermal resistance (the m of R in the formula---building enclosure ²K/W)

Q _Ij---the j time measured value of building enclosure internal surface temperature (℃)

Q _Ej---the j time measured value of building enclosure hull-skin temperature (℃)

q _j---the j time measured value (W/m of heat flow density ²)

Can calculate the thermal resistance R of building enclosure, again with R substitution K=1/ (R _i+ R+R _e)

In the formula: K---the heat transfer coefficient (W/m of building enclosure ².k)

R _i---heat exchange resistance of interior surface, by national standard " code for thermal design of civil buildings "

GB50176 stipulates to adopt

R _e---outside surface heat exchange resistance, by national standard " code for thermal design of civil buildings "

GB50176 stipulates to adopt

Then the Coefficient K of building enclosure just can be obtained.

The beneficial effect of advantage of the present invention and generation is:

1, the present invention avoids concentrated owing to the time of detecting at heating period, workload is concentrated, brings difficulty to testing.Using temperature automatically controlled constant temperature oven, is to cause under the environment of the temperature difference the people, carries out the scene of buildings exterior-protected structure heat transfer coefficient and detects, and it is stable that the value of heat transfer coefficient reaches quickly, and restricted factor is few;

2, chart as can be seen, under the artificial temperature control condition, the value of heat transfer coefficient is easier to reach stable, sense cycle can suitably shorten, and does not influence the examination of completion of works, can reduce labour intensity, improves plant factor.

The on-the-spot concrete detection method of the present invention is provided by drawings and Examples

Description of drawings

Fig. 1 is a pick-up unit synoptic diagram of the present invention

Fig. 2 is heat transfer coefficient-time plot under the artificially controlling temperature condition of the present invention

Fig. 3 is indoor and outdoor temperature-time plot under the artificially controlling temperature condition of the present invention

Fig. 4 is heat transfer coefficient-time plot under the heating condition

Fig. 5 is indoor and outdoor temperature-time plot under the heating condition

Embodiment

Embodiment 1 is with reference to accompanying drawing, heat flow meter 3 surfaces are coated with one deck and approach and uniform butter layer, make heat flow meter 3 can be bonded to the surface of the body of wall of surveying 1, push to outer rim from heat flow meter 3 centers then, get rid of the bubble between heat flow meter 3 and the body of wall 1, pasted the spot on back wiping heat flow meter 3 surfaces, be fixed on body of wall 1 surface with plastic adhesive tape paper.Temperature sensor 4 adopts double faced adhesive tape to stick on the two sides of tested district body of wall 1, and promptly medial surface temperature sensor 4 is near heat flow meter 3, and hull-skin temperature sensor 4 sticks on and heat flow meter 3 corresponding positions, and will be evenly distributed.Then, adopt multiplex transmission line 5 that heat flow meter 3, temperature sensor 4 are connected with the automatic scan tester 6 of temperature hot-fluid, more temperature automatically controlled constant temperature oven 2 is close to the metope that is furnished with heat flow meter 3, temperature sensor 4.Temperature automatically controlled constant temperature oven 2 contains micro computer time controller, temperature controller, compressor, electrothermal tube etc.Determine that according to environment temperature temperature automatically controlled constant temperature oven 2 is refrigeration or heating when working; Open compressor during refrigeration, make temperature automatically controlled constant temperature oven 2 temperature reduce to setting value, the micro computer time controller is controlled two compressor alternations, and temperature controller is controlled constant temperature automatically; Open electrothermal tube during heating, make temperature automatically controlled constant temperature oven 2 temperature reach setting value, temperature controller is controlled constant temperature automatically.When body of wall 1 heat transfer tended towards stability, heat flow meter 3 readings also tended towards stability.Temperature hot-fluid scan tester 6 reads thermopower E, interior exterior wall table temperature and store automatically.When measuring heat of heat flow meter coefficient C is known, can calculate heat flow density q by formula q=CE _J1, q _J2, q _J3, q _J4, q _J5, the touring automatic tester 6 of temperature hot-fluid is J measured data Q of record automatically _I1, Q _E1, Q _I2, Q _E2, Q _I3, Q _E3, Q _I4, Q _E4, Q _I5, Q _E5Adopt arithmetic mean method, can calculate the thermal resistance of fender structure by following formula, promptly

$R=\frac{\underset{j=1}{\overset{n}{\mathrm{\Σ}}}(Q_{\mathrm{ij}}-Q_{\mathrm{ej}})}{\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{q}_j}$

Thermal resistance (the m of R in the formula---building enclosure ²K/W)

Q _Ij---the j time measured value of building enclosure internal surface temperature (℃)

Q _Ej---the j time measured value of building enclosure hull-skin temperature (℃)

q _j---the j time measured value (W/m of heat flow density ²)

Again with R substitution K=1/ (R _i+ R+R _e)

In the formula: K---the heat transfer coefficient (W/m of building enclosure ².k)

R _i---heat exchange resistance of interior surface, stipulate to adopt by national standard " code for thermal design of civil buildings " GB50176

R _e---outside surface heat exchange resistance, stipulate to adopt by national standard " code for thermal design of civil buildings " GB50176

Then the Coefficient K of building enclosure just can be obtained.

Embodiment 2 the present invention contrast in the detection and the heating phase conventional sense of non-heating period to a certain room heat transfer coefficient of outer wall.

Method of operating is as embodiment 1.

Detect and divide artificially controlling temperature to detect and the detection of heating phase

1, artificially controlling temperature detects

The present invention adopts opening 1 * 1m ²Temperature automatically controlled constant temperature oven 2 (heating), testing result with Fig. 2,

The statement of Fig. 3 curve map form.

Transverse axis is the continuity of detection time, and each digit is 0.5h, and the longitudinal axis is represented heat transfer coefficient (W/m ².K.)。By curve as can be seen, the value of heat transfer coefficient is more stable, and reaches stable faster, begins to stablize near the 30th, and promptly the 15th h begins to stablize.By calculating, the mean value of heat transfer coefficient is K=1.47W/ (m when stablizing ².K).From Fig. 3 temperature-time plot as can be seen, indoor artificial control temperature curve 1 and outdoor natural temperature curve 2 tend towards stability very soon through 30h.

2, the heating phase is detected

Testing result is represented with Fig. 4 heat transfer coefficient-time curve and Fig. 5 temperature-time curve.

As can be seen from Figure 4, heat transfer coefficient continues the variation of generating period in time, and fluctuation is very big; As can be seen from Figure 5, heating indoor temperature curve ratio is more steady, outdoor natural temperature curve

2 fluctuation ratios are bigger.

The value that adopts the method for average to calculate heat transfer coefficient is K=1.54W/ (m ²K).

Guarantee the reliability of data, need the mutual checking in several cycles, so detection time generally need be very long.Detect minimum needs 96 hours by the JGJ132-2001 standard code, promptly need to write down 192 groups of data.

Hence one can see that, and artificially controlling temperature detects can substitute the detection of heating phase fully, and its advantage with self has remedied the deficiency of heating phase detection.

Claims (1)

1, a kind of buildings exterior-protected structure heat transfer coefficient in-situ check and test method is heat flow meter (3) to be sticked on the inside surface of tested body of wall (1), and should contacts fully with inside surface; Temperature sensor (4) is near heat flow meter (3), and hull-skin temperature sensor (4) sticks on the corresponding position of heat flow meter (1), and is evenly distributed; Adopt multiplex transmission line (5) that heat flow meter (3), temperature sensor (4) are connected with the automatic scan tester of temperature hot-fluid (6); It is characterized in that: temperature automatically controlled constant temperature oven (2) is close to the metope that is furnished with heat flow meter (3), temperature sensor (4); Regulate temperature automatically controlled constant temperature oven (2), make that tested district metope is inside and outside to be produced certain temperature difference and tend towards stability; When certain hot-fluid vertical current superheat flow measuring head, produce certain electromotive force E, just can determine to flow through the heat flow density of heat flow meter (3) by formula q=CE (C is the gauge head coefficient, after gauge head is made, definite constant exactly); The automatic scan tester of temperature hot-fluid (6) writes down j measured value Q of building enclosure surfaces externally and internally temperature control automatically _IjQ _EjWith thermopower E, data processing is with measured value Q _Ij, Q _Ej, q substitution following formula:

$R=\frac{\underset{j=1}{\overset{n}{\mathrm{\Σ}}}(Q_{\mathrm{ij}}-Q_{\mathrm{ej}})}{\underset{j=1}{\overset{n}{\mathrm{\Σ}}}{q}_j}$

Thermal resistance (the m of R in the formula---building enclosure ².K/W)

Q _Ij---the j time measured value of building enclosure internal surface temperature (℃)

Q _Ej---the j time measured value of building enclosure hull-skin temperature (℃)

q _j---the j time measured value (W/m of heat flow density ²)

Again with R substitution K=1/ (R _i+ R+R _e)

In the formula: K---the heat transfer coefficient (W/m of building enclosure ².k)

R _i---heat exchange resistance of interior surface, stipulate to adopt by national standard " code for thermal design of civil buildings " GB50176

R _e---outside surface heat exchange resistance, stipulate to adopt by national standard " code for thermal design of civil buildings " GB50176

By calculating, then the Coefficient K of building enclosure just can be obtained.

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