CN104680004A - Building energy-saving rate calculation method - Google Patents

Abstract

The invention discloses a building energy-saving rate calculation method, which can objectively and accurately measure the advantages and disadvantages of building energy-saving designs, overcomes the defect that the conventional method cannot accurately evaluate the energy-saving rates of buildings, and is used for guiding the design of building envelope structures. The method creates a building standard model according to envelope structure thermal design parameter limit values specified in the current national standard regulating building design schemes and energy-saving designs and building envelope structure and indoor and outdoor thermal balance equations to objectively and accurately obtain daily mean air temperature, then utilizes reference energy consumption and building energy consumption to judge the energy-saving rate of a building, and makes a judgment on whether a building design meets the requirement of the current energy-saving design standard. The building energy-saving rate calculation method is suitable for judging the energy-saving performance of building envelope structures at the design stage of different types of buildings in different climatic regions, and is used for guiding the thermal design of buildings and envelope structures.

Description

A kind of Saving In Buildings energy rate computing method

Technical field

The present invention relates to building energy saving field, be specifically related to a kind of new building energy saving rate computing method, in order to objective evaluation Saving In Buildings energy rate, can be used as architectural design reference simultaneously.

Background technology

The size of a building energy consumption, depends on the factor of three aspects: the thermal and insulating performance of (1) building enclosure, comprises exterior wall, door and window, the isostructure thermal and insulating performance of roofing; (2) operational efficiency of device systems, comprises the selection of device systems, operation and management situation; (3) build the heat demand of user, comprise the requirement to thermal environments such as architecture indoor temperature, humidity.Wherein, the performance of building enclosure and the heat demand of user determine the energy requirements size of the various services such as building and heating, air-conditioning, ventilation, illumination jointly; And the efficiency of device systems determines the energy quantity used for meeting this energy requirements.

For saving building energy consumption, China put into effect successively or have updated the design standard for energy efficiency of buildings for Different climate district, different building type from 1986, as: " severe cold, cold district energy Saving Design of Residential Buildings standard " JGJ26, " hot-summer and cold-winter area energy Saving Design of Residential Buildings standard " JGJ134, " Residential Buildings In Hot Summer And Warm Winter energy saving igniter " JGJ75 and " public building energy design standards " GB50189.Every ministerial standard, using fractional energy savings as building energy conservation target, by 2010, proposes the fractional energy savings target of 30%, 50% and 65% respectively.Example is calculated as with Residential Buildings Energy rate, three kinds of fractional energy savings calculate like this to get: the actual measurement heating energy consumption value defining 1980 ~ 1981 years northern a collection of typical building Heating Periods investigated on the spot is " 100% ", and different fractional energy savings standard-required realizes heating energy consumption energy-conservation target of 30%, 50% and 65% of difference on the basis of above-mentioned " 100% ".Wherein, heating energy consumption comprises the heat, electric energy and the heat consumption of building that consume in heating system operational process, and fractional energy savings is at interior total fractional energy savings containing device energy conservations such as heating system pipe network, boilers.

For meeting the requirement of fractional energy savings, above-mentioned design standards carries out specifying and control that (" public building energy design standards " also specify heating for the performance of building enclosure according to different climatic regions, ventilate and the requirement of artificial atmosphere energy-saving design), namely compulsive clause is passed through, define the performance parameter of each component of building enclosure, as in residential architecture to building Shape Coefficient, area ratio of window to wall, the heat transfer coefficient of building enclosure, the airtight performance etc. of exterior window and open type balcony, when designed building meets the requirement of these compulsory performance parameters completely, just be judged as energy saving building.If build a certain index when can not reach standard-required, standard-required must carry out balance to Thermal Performance of Envelope Structure and judge, namely provides a standard compliant energy saving building as with reference to building, calculates the energy consumption of designed building.The energy of the building designed by calculating and reference building is consuming time, and except building enclosure, also need the information of building user's life style and device systems aspect, standard supposes it, as basis.Putting before this, if when designed building energy consumption index is less than with reference to building energy consumption index, can judge that this building meets the requirement of design standards fractional energy savings.

Because people always there are differences the demand of living environment and external climate, therefore human needs one can provide keep out wind and rain, keep out the cold the space of avoiding heat, to reduce the adverse effect brought from external climate system.But single with regard to building, it can not be entirely again the indoor thermal environment that people provide comfortable, and other device systems also must be relied on to meet the comfortableness demand of people, and therefore building energy consumption produces, this is the energy consumption attribute of building.As can be seen here, build and weaken external climate and provide except good living environment except needing to bear for people, also should as far as possible excellent in design to reduce the level of building energy consumption.Therefore, good energy-saving design in construction, fully can reduce the difference between weather and human comfort's sexual demand, also can reduce building energy consumption.

From architectural design angle, this just requires that architect must make full use of design techniques and improve the energy-efficient performance built.Accurately will judge the quality of energy-saving design in construction, need to pass judgment on its energy-efficient performance, just necessary clear and definite buildings is to the contribution rate of whole building energy conservation, i.e. the fractional energy savings size of buildings self.But, each standard that just current China is existing, the method for there is no reaches this object, traces it to its cause, and mainly contains:

(1) existing standard is the actual measurement heating energy consumption value of a collection of typical building Heating Period investigated on the spot with 1980 ~ 1981 years north is benchmark building energy saving rate, this reference energy consumption is only for the northern area of China, not with reference to China's other climatic regions building status of energy consumption at that time, itself is not rigorous, science, thus causes the fractional energy savings calculated on this basis just can not weigh the energy-saving horizontal of building self well; (2) about the calculating of building energy saving rate, be contain building and device systems two parts at interior total fractional energy savings, accurately cannot be separated and judge the amount of energy saving that buildings self is born.

In addition, the execution of act.std also brings following problem:

(1) because the energy-efficient performance of each standard to architectural exterior-protecting construction has formulated harsh quantizating index, as long as each design parameter that building designers specify according to standard (as: heat transfer coefficient etc. of each component of area ratio of window to wall, building enclosure), just can design qualified energy saving building.The architectural design of this " industrialization " and build model, make architect have no way of playing its design ability, cause same type architectural style similar, given up and built the aesthetic properties that should have; (2) residing Different climate district or dissimilar building perform different energy saving igniter, the content that each standard specifies and energy-saving index are not quite similar, this causes the judgement of building energy conservation performance to lack unified, just scale, the quality of its buildings design itself cannot be compared between building, more scientifically can not calculate the ratio that building energy saving rate is shared in total fractional energy savings.

How accurately to pass judgment on the energy-efficient performance of buildings self simply, weigh the quality of energy-saving design in construction, this needs the unified method of a convenient operation to judge the fractional energy savings building self.Therefore, be necessary to propose a kind of new building energy saving rate computing method.

Summary of the invention

The deficiency existed for above-mentioned traditional architecture fractional energy savings computing method or defect, the object of the invention is to, based on " weather-building-people " three's mathematical model, a kind of new building energy conservation performance judgment thought is proposed, a kind of new building energy saving rate computing method are proposed accordingly, with quality that is objective, that weigh building energy-saving design exactly, overcome the deficiency accurately cannot evaluating buildings self fractional energy savings in existing method, in order to instruct the Thermal Design of building and building enclosure, thus improve the fractional energy savings of building.

In order to realize above-mentioned task, the present invention by the following technical solutions:

. a kind of Saving In Buildings energy rate computing method, comprise the following steps:

Step one, obtains buildings and plans to build the annual every per day outside air temperature in ground;

Step 2, obtain the per day natural room temperature of buildings, concrete steps comprise:

Building envelope being carried out layering by material, exterior wall and roofing are divided into n layer, m layer respectively, all successively increasing progressively according to arriving outdoor direction indoor;

Set up indoor air temperature node thermal balance model:

$\begin{array}{c}C{\mathrm{\ρ}}_{\mathrm{in}}V\frac{{\mathrm{dt}}_{D,i,\mathrm{in}}}{\mathrm{d\τ}}=k_{w,\mathrm{in}}{F}_w(t_{w,1}-t_{D,i,\mathrm{in}})+k_{r,\mathrm{in}}{F}_r(t_{r,1}-t_{D,i,\mathrm{in}})+\\ (t_{D,i,\mathrm{out}}-t_{D,i,\mathrm{in}})(C{\mathrm{\ρ}}_{\mathrm{out}}\mathrm{VN}/3600+F_C\·k_C)+Q_C\end{array}---\left(1\right)$

In formula (1), C is the specific heat of air, ρ _infor the density of room air, V is room volume, t _{d, i, in}, t _{d, i, out}be respectively moment D day i-th indoor, outside air temperature, τ is the time, k _{w, in}, k _{r, in}be respectively the heat transfer coefficient between room air and the 1st layer of exterior wall, roofing, F _w, F _wbe respectively the area of exterior wall, roofing, t _{w, 1}, t _{r, 1}be respectively be the 1st layer of outer wall material, the 1st layer of roofing in the temperature in moment D day i-th, C is air specific heat, ρ _outfor the density of outdoor air, N is rate of ventilation, F _cfor outer window ara, k _cfor the heat transfer coefficient of window, Q _cfor being obtained the indoor hourly cooling load that heat causes by window insolation;

Solve formula (1), obtain buildings D day i-th moment indoor temperature t _{d, i, in}, then obtain the annual average indoor temperature of buildings

Step 3, according to the average of the whole year outside air temperature that step one obtains generate annual outdoor temperature curve f _out(x), in the coordinate axis of temperature curve, x-axis is the time, and y-axis is temperature; Accounting temperature curve f _outx area S that () and average of the whole year confort line enclose;

Step 4, according to the indoor per day natural room temperature whole year that step 2 obtains generate annual indoor temperature curve f _inx (), calculates f _inx area S ' that () and annual confort line enclose;

Step 5, calculates building and regulates energy consumption: Δ S=S-S ';

Step 6, calculates building energy saving rate J:

$J=\frac{\mathrm{\ΔS}}{S}\×100\%$

Step 7, according to the design standard for energy efficiency of buildings of building design office foundation, building and building enclosure Thermal Design parameter according to energy-saving design parameter limit value value each in standard, set up actual standard model, calculate building energy saving rate J corresponding to master pattern according to step one to the method that step 6 is identical ₀;

Step 8, the J that comparison step seven obtains ₀with the J that step 6 obtains, if J>J ₀, then judge that this architectural design meets the requirement of existing energy saving igniter; If J<J ₀, so architect can change the design parameter of building and building enclosure Thermal Design, by step 2 to step 6 cycle calculations, until J>J ₀.

Further, the solution procedure of indoor air temperature node thermal balance equation comprises:

In every one deck of exterior wall and roofing, choose temperature nodes, set up the thermal balance equation of exterior wall and roofing:

Exterior wall xth (x=1,2 ..., n) thermal balance equation of layer temperature nodes is:

Roofing y (y=1,2 ..., m) thermal balance equation of layer temperature nodes is:

Formula (2) is in formula (7): C _w,xand C _r,yfor the specific heat of exterior wall and the every layer material of roofing, δ _w,x, δ _r,ybe respectively the thickness of exterior wall, the every layer material of roofing, ρ _w,x, ρ _r,ybe respectively the density of exterior wall, the every layer material of roofing, t _w,x, t _r,ybe respectively the temperature for temperature nodes in xth layer outer wall material, y layer roofing, k _w,x, k _r,ybe respectively xth layer and (x+1)th layer exterior wall, heat transfer coefficient between y layer and y+1 layer roofing, k _{w, out}, k _{r, out}be respectively exterior wall n-th layer, heat transfer coefficient between roofing m layer and outdoor air, t _safor outdoor air integrated temperature;

Wherein:

$k_{w,\mathrm{in}}=\frac{1}{\frac{1}{{\mathrm{\&alpha;}}_1}+\frac{{\mathrm{\&delta;}}_{w,1}}{2{\mathrm{\&lambda;}}_{w,1}}}---\left(8\right)$

$k_{w,x}=\frac{1}{\frac{{\mathrm{\&delta;}}_{w,x}}{2{\mathrm{\&lambda;}}_{w,x}}+\frac{{\mathrm{\&delta;}}_{w,x+1}}{2{\mathrm{\&lambda;}}_{w,x+1}}}---\left(9\right)$

$k_{w,\mathrm{out}}=\frac{1}{\frac{1}{{\mathrm{\&alpha;}}_2}+\frac{{\mathrm{\&delta;}}_{w,n}}{2{\mathrm{\&lambda;}}_{w,n}}}---\left(10\right)$

Formula (8) in formula (10), α ₁for the convection transfer rate between room air and the 1st layer of exterior wall, δ _{w, 1}be the thickness of the 1st layer of outer wall material, λ _{w, 1}be the coefficient of heat conductivity of the 1st layer of outer wall material, α ₂for the convection transfer rate between n-th layer exterior wall and outdoor air;

Subscript w in formula (8), formula (9) and formula (10) is replaced with subscript r, and subscript x replaces with subscript y, and subscript m replaces subscript n, and formula is constant, then obtain the k of roofing _{r, in}, k _r,yand k _{r, out};

T in formula (4) _safor:

$t_{\mathrm{sa}}=t_{D,i,\mathrm{out}}+\frac{{\mathrm{\&rho;}}_{s}I}{{\mathrm{\&alpha;}}_3}---\left(11\right)$

In formula (11), ρ _sfor solar radiation absorbility factor; α ₃for outside surface convection transfer rate;

Q in formula (1) _cfor:

Q _C＝F _C·X _g·X _d·J _wτ(12)

In formula (12), X _gfor the structure correction factor of window; X _dfor place correction factor; J _{w τ}for inscribing through the refrigeration duty intensity without the radiation of sunshading facility glass solar when calculating;

In formula (2) to formula (12) each formula, the implication of NM parameter, identical with in the implication of front explanation;

Association type (2) solves formula (1) to formula (12), can obtain buildings D day i moment natural room temperature t _{d, i, in}; The indoor temperature in the whole year of trying to achieve in each moment is averaged, obtains the annual average indoor temperature of buildings

The present invention compared with prior art has following technical characterstic:

1. the thought of these building energy saving rate computing method is different from act.std, it is with directly reflecting that the main index " air themperature " of indoor and outdoor weather conditions and human comfort's degree weighs the energy consumption level of buildings self, the area enclosed by method counting chamber internal and external temperature curve and the evenly heat comfort curve of definite integral reflects energy consumption size, computation process science, objective;

2. these computing method establish with indoor human body hot comfort to retrain building energy-saving design, the size that building resists weather effect is characterized with single Saving In Buildings energy rate index, and contain the Schematic Design Stage building enclosure essential structure parameter and each several part material type, size, functional parameter is (as specific heat, density, coefficient of heat conductivity etc.) complicated and mathematical model that is comprehensively " weather-building-people " three, fully illustrate the impact of building enclosure tectonic system design in whole energy-saving design in construction, and the design of building enclosure can be instructed conversely with fractional energy savings index,

3. with more simple and clear and can " the air themperature index " of personal understanding, replace the compulsive clause regulation that the performance parameter of each component of building enclosure is done specified in original standard, whether contributing to architect, to pass judgment on energy-saving design voluntarily in the design phase excellent, and carry out project setting, optimization, more be conducive to the design ability that architect plays self, good design and creation is carried out on the basis meeting existing energy saving igniter, avoids the phenomenon occurring the regional culture disappearance such as method for designing " stereotyped ", city appearance " thousand city one sides ";

4. the method is the computing method for the dissimilar building energy saving rate in all climatic regions, has science, just feature, and unified fractional energy savings calculating makes building energy conservation performance and design quality more easily weigh and pass judgment on, and has applicability widely.

Accompanying drawing explanation

Fig. 1 is the new building energy saving rate Computing Principle model of the present invention;

Fig. 2 is the temperature nodes schematic diagram of exterior wall;

Fig. 3 is the temperature nodes schematic diagram of roofing;

Fig. 4 is specific embodiment of the invention architectural plan;

Fig. 5 is embodiment external wall structure way schematic diagram;

Fig. 6 is embodiment roof structure way schematic diagram;

Fig. 7 is that specific embodiment of the invention building energy saving rate calculates data plot;

Fig. 8 is calculation flow chart of the present invention;

In Fig. 5 and Fig. 6, the implication of each label is:

1-polymer mortar, 2-clay solid brick, 3-sand-cement slurry, 4-EPS plate, 5-sand-cement slurry, 6-reinforced concrete, 7-boiler slag, 8-expansion polyphenyl plate, 9-haydite, 10-C15 concrete, 11-water barrier.

Embodiment

Computing Principle of the present invention is as follows with the main concept term related to:

Computing Principle:

A kind of new building energy saving rate computing method, with reflecting that " the air themperature index " of indoor and outdoor weather conditions characterizes energy consumption level, be applicable to any climatic region and all types of building, and the synthesis energy saving effect of buildings self whole year can be reflected, Computing Principle can be expressed as by mathematical formulae image:

The adjustment energy consumption of reference energy consumption-building energy consumption=building

New building energy saving rate Computing Principle model, namely " weather-building-people " three's mathematical model can be illustrated by Fig. 1 image, and wherein x-axis represents the computing time of energy consumption, and the time cycle that the present invention gets fractional energy savings calculating is 365, and with " day " for closing unit, unit: sky; Y-axis represents air themperature, unit: DEG C.

Concept term:

Annual outdoor temperature curve

From the annual outdoor weather data in city, buildings place or area, obtain annual outdoor per day air themperature data, the curve drawn is referred to as " annual outdoor temperature curve ", and its equation can be expressed as f _out(x).

Annual indoor temperature curve

Because these computing method directly depend on indoor and outdoor temperature data, therefore for natural room temperature, need to set up and temperature computation process through strict model, by buildings exterior-protected structure layering, drawing of a building and design parameter, utilize thermal balance equation calculate objectively annual every day by time natural room temperature, per diem add up its mean value, then utilize these Plotting data to become curve, be called " annual indoor temperature curve ", its equation is expressed as f _in(x); Indoor temperature curve according to calculation of design parameters out, is an objective metric, and for the buildings according to this drawing and parameter designing, can compares according to this metric and result of calculation, to instruct the design process of building.

Average of the whole year confort line

Indoor temperature line when annual human body sensory is comfortable, its equation can be expressed as f _comf(x), the mean value of maximum interval 16 ~ 28 DEG C of comfort temperature in comfort temperature of the present invention is got " covil construction heating ventilator and In Air Conditioning Design specification " GB50736-2012, i.e. f _comf(x)=22 DEG C.

Reference energy consumption

The comfortableness demand of people and external climate always there are differences, the energy consumption eliminated required for this species diversity is defined as " reference energy consumption ", the area (S) that available annual outdoor temperature curve and average of the whole year confort line enclose represents, size is tried to achieve by the mode of definite integral.

Building energy consumption

The indoor climate formed after buildings is resisted outdoor climate, the energy consumption produced when being adjusted to human comfort is defined as " building energy consumption ", the area (S ') that available annual indoor temperature curve and average of the whole year confort line enclose represents, size is tried to achieve by the mode of definite integral.

Building regulates energy consumption

By the reduction of the reference energy consumption that utilization design method makes outdoor climate produce, be defined as " building regulates energy consumption ", the area (Δ S) that available annual outdoor temperature curve and annual indoor temperature curve enclose represents, size Δ S=S-S '.

Master pattern

The limiting design value that country's (or local) act.std that buildings exterior-protected structure Thermal Design parameter (as: shape coefficient of building, area ratio of window to wall, building enclosure each position thermal property parameter etc.) gets energy-saving design in construction institute foundation specify, foundation with the model for calculating new building energy saving rate built original design and be substantially consistent.

The present invention proposes a kind of new Saving In Buildings energy rate computing method, passes judgment on, specifically comprise following steps to buildings self energy-efficient performance:

Step one, obtains the annual outdoor weather data in buildings location, extract annual every day by time outside air temperature t _{d, i, out}, DEG C (1≤D≤365,1≤i≤24), can be calculated per day outside air temperature dEG C; Here annual outdoor weather data can be the actual observed values of meteorological station, also can be typical meteorological year, the meteorological annual data of standard, the daily mean of the meteorologic parameter used mainly annual outside air temperature;

Step 2, calculates Indoor environment temperature, comprises the following steps:

Step S20, carries out layering by building envelope by material, and exterior wall and roofing are divided into n layer, m layer respectively, all successively increases progressively according to arriving outdoor direction indoor; All choose temperature nodes on each layer; The central point of each layer material can be chosen as temperature nodes (particle);

Step S21, gathers the following essential information of buildings according to building design drawing:

The area F of exterior wall _w, m ²; The thickness δ of the every layer material of exterior wall _w,x, m (1≤x≤n); The area F of roofing _r, m ²; The thickness δ of the every layer material of roofing _r,y, m (1≤y≤m); The area F of exterior window _c, m ²; Room volume V in buildings, m ³;

Step S22, adopts conventional method to gather the following calculating parameter of buildings:

D day i moment outside air temperature t _{d, i, out}, DEG C (1≤D≤365,1≤i≤24);

The specific heat C of exterior wall and the every layer material of roofing _w,xand C _r,y, J/ (kgK), density p _w,xand ρ _r,y, kg/m ³, coefficient of heat conductivity λ _w,xand λ _r,y, W/ (mK); Solar radiation absorbility factor ρ _s; Solar irradiance I, W/m ²;

The heat transfer coefficient k of window _c, W/ (m ²k); Air specific heat C, J/ (kgK); Atmospheric density ρ, kg/m ³; Rate of ventilation N, 1/h; The structure correction factor X of window _g; The place correction factor X of windowpane solar radiation refrigeration duty intensity _d; Inscribe during calculating through the refrigeration duty intensity J without the radiation of sunshading facility glass solar _{w τ}, W/m ²; These parameters can be obtained by Query Design drawing;

Step S23, buildings natural room temperature is studied, a system of particles having thermal capacity is regarded as by the whole interior space, there are same quality and thermal capacity in this system of particles and indoor, the wall body of building external envelope structure is divided into some layers according to S20, every one deck particle (namely above-mentioned temperature nodes) represents quality and the thermal capacity of this layer, sets up heat balance equation:

The thermal balance model of indoor air temperature node:

$\begin{array}{c}C{\mathrm{\&rho;}}_{\mathrm{in}}V\frac{{\mathrm{dt}}_{D,i,\mathrm{in}}}{\mathrm{d\&tau;}}=k_{w,\mathrm{in}}{F}_w(t_{w,1}-t_{D,i,\mathrm{in}})+k_{r,\mathrm{in}}{F}_r(t_{r,1}-t_{D,i,\mathrm{in}})+\\ (t_{D,i,\mathrm{out}}-t_{D,i,\mathrm{in}})(C{\mathrm{\&rho;}}_{\mathrm{out}}\mathrm{VN}/3600+F_C\&CenterDot;k_C)+Q_C\end{array}---\left(1\right)$

In order to solving equation (1), the thermal balance equation can setting up exterior wall and each layer of roofing is assisted and is solved:

Exterior wall xth (x=1,2 ..., n) thermal balance equation of layer temperature nodes is:

Roofing y (y=1,2 ..., m) thermal balance equation of layer temperature nodes is:

Formula (1) is in formula (7), and C is the specific heat of air, J/ (kgK); ρ _infor the density of room air, kg/m ³; ρ _outfor the density of outdoor air, kg/m ³; τ is the time, s; k _{w, in}, k _{r, in}be respectively the heat transfer coefficient between room air and the 1st layer of exterior wall, roofing, W/ (m ²k); k _w,x, k _r,ybe respectively xth (1≤x≤n-1) layer and (x+1)th layer exterior wall, y (1≤y≤m-1) heat transfer coefficient between layer and y+1 layer roofing, W/ (m ²k); k _{w, out}, k _{r, out}be respectively exterior wall n-th layer, heat transfer coefficient between roofing m layer and outdoor air, W/ (m ²k); t _safor outdoor air integrated temperature, DEG C; t _w,x, t _r,ybe respectively exterior wall, temperature that each layer of roofing concentrates particle, DEG C; Q _cfor being obtained the indoor hourly cooling load that heat causes by window insolation, W;

Being calculated as follows of the parameter related in formula (1) ~ formula (7):

$k_{w,\mathrm{in}}=\frac{1}{\frac{1}{{\mathrm{\&alpha;}}_1}+\frac{{\mathrm{\&delta;}}_{w,1}}{2{\mathrm{\&lambda;}}_{w,1}}}---\left(8\right)$

$k_{w,x}=\frac{1}{\frac{{\mathrm{\&delta;}}_{w,x}}{2{\mathrm{\&lambda;}}_{w,x}}+\frac{{\mathrm{\&delta;}}_{w,x+1}}{2{\mathrm{\&lambda;}}_{w,x+1}}}---\left(9\right)$

$k_{w,\mathrm{out}}=\frac{1}{\frac{1}{{\mathrm{\&alpha;}}_2}+\frac{{\mathrm{\&delta;}}_{w,n}}{2{\mathrm{\&lambda;}}_{w,n}}}---\left(10\right)$

In formula (8) ~ (10), α ₁for the convection transfer rate between room air and the 1st layer of exterior wall or roofing (after subscript is replaced in these three formula), get 8.72W/ (m ²k); δ _{w, 1}be the thickness of the 1st layer of outer wall material, m; λ _{w, 1}be the coefficient of heat conductivity of the 1st layer of outer wall material, W/ (mK); α ₂for n-th layer exterior wall or the convection transfer rate between m layer roofing and outdoor air, get 23.3W/ (m ²k);

Adopting uses the same method can draw the k of roofing _{r, in}, k _r,yand k _{r, out}, replace with subscript r by the subscript w in formula (8), formula (9) and formula (10), subscript x replaces with subscript y, and subscript m replaces subscript n, and formula is constant; After replacing, the implication of each parameter representative is identical with front;

T in formula (4) _safor:

$t_{\mathrm{sa}}=t_{D,i,\mathrm{out}}+\frac{{\mathrm{\&rho;}}_{s}I}{{\mathrm{\&alpha;}}_3}---\left(11\right)$

In formula (11), ρ _sfor solar radiation absorbility factor; I implication is identical with front, is solar irradiance in level or vertical plane, W/m ²; α ₃for outside surface convection transfer rate, get 19.0W/ (m ²k);

Q in formula (1) _cfor:

Q _C＝F _C·X _g·X _d·J _wτ(12)

In formula (12), X _gfor the structure correction factor of window; X _dfor place correction factor; J _{w τ}for inscribing through the refrigeration duty intensity without the radiation of sunshading facility glass solar when calculating, W/m ².

Step S24, solves formula (1) ~ formula (7), can obtain buildings D day i moment natural room temperature t _{d, i, in}, DEG C; The indoor temperature in the whole year of trying to achieve in each moment is averaged, the annual indoor per day natural room temperature of buildings can be obtained dEG C, concrete steps are:

Replace the differential in formula (1) ~ formula (7) by difference, namely replace d τ with △ τ, make with note angle " z " is the value in τ=z △ τ moment, and " z+1's " is the value in τ=(z+1) △ τ moment.Get △ τ=3600s computing time, obtain the Algebraic Equation set of the easy iteration of computing machine through conversion:

$\begin{array}{c}{t}_{D,i\_\mathrm{in}}^{z+1}=\\ \frac{{\mathrm{C\&rho;}}_{\mathrm{in}}{\mathrm{Vt}}_{D,i,\mathrm{in}}^z/3600+k_{w,\mathrm{in}}{F}_w{t}_{w,1}^z+k_{r,\mathrm{in}}{F}_r{t}_{r,1}^z+t_{D,i,\mathrm{out}}^z({\mathrm{C\&rho;}}_{\mathrm{out}}\mathrm{VN}/3600+F_C\&CenterDot;k_C)+Q_C^z}{{\mathrm{C\&rho;}}_{\mathrm{in}}V/3600+k_{w,\mathrm{in}}{F}_w+k_{r,\mathrm{in}}{F}_r+{\mathrm{C\&rho;}}_{\mathrm{out}}\mathrm{VN}/3600+F_C\&CenterDot;k_C}\end{array},---\left(13\right)$

For body of wall:

For roofing:

By carrying out list statistics to all parameters in formula (13) ~ (19), the natural room temperature t inscribing buildings when trying to achieve each calculating can be calculated _{d, i, in}, the buildings natural room temperature inscribed when being calculated every day is respectively averaged, and can obtain indoor per day natural room temperature indoor for the whole year obtained per day natural room temperature line can be obtained annual average indoor temperature curve.

Step 3, the whole year that step one is obtained per day outside air temperature generate annual outdoor temperature curve f _outx (), utilizes the method for integration to ask itself and average of the whole year confort line (f _comf(x)=22 DEG C) the area S that encloses, i.e. reference energy consumption, that is:

$S=\underset{a}{\overset{b}{\&Integral;}}{f}_{\mathrm{out}}\left(x\right)\mathrm{dx}---\left(20\right)$

In formula (20), a, b represent the time at the whole story that fractional energy savings calculates, and value is 0,365 respectively; f _outx () is annual outdoor temperature curvilinear equation; calculate by definite integral method, see formula (21):

$\underset{a}{\overset{b}{\&Integral;}}f\left(x\right)\mathrm{dx}\&ap;\underset{D=1}{\overset{l}{\mathrm{\&Sigma;}}}{y}_D\mathrm{\&Delta;x}=\frac{b-a}{l}\underset{D=1}{\overset{l}{\mathrm{\&Sigma;}}}{y}_D---\left(21\right)$

In formula (21), l is constant, represents energy consumption calculation number of days, gets 365 days; y _dbe D day (1≤D≤365) difference between mean daily temperature and comfort temperature, DEG C; Final reference energy consumption can be expressed as formula (22):

$S=\frac{b-a}{l}\underset{D=1}{\overset{l}{\mathrm{\&Sigma;}}}{y}_{D,\mathrm{out}}=\underset{D=1}{\overset{365}{\mathrm{\&Sigma;}}}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{out}}-t_{\mathrm{comf}}|=\underset{D=1}{\overset{365}{\mathrm{\&Sigma;}}}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{out}}-22|---\left(22\right)$

In formula (22), y _{d, out}be D day outdoor average air temperature and the difference of annual comfort temperature, DEG C; be D day outdoor average air temperature, DEG C; t _comffor average of the whole year comfort temperature, DEG C, the present invention gets 22 DEG C;

Step 4, the per day natural room temperature in the indoor whole year that step 2 is obtained generate annual indoor temperature curve f _inx (), utilizes the method for integration to ask itself and average of the whole year confort line: f _comfx area S ' that ()=22 DEG C enclose, i.e. building energy consumption, see formula (23):

$S^{\&prime;}=\underset{a}{\overset{b}{\&Integral;}}{f}_{\mathrm{in}}\left(x\right)\mathrm{dx}---\left(23\right)$

In formula (23), a, b represent the time at the whole story that fractional energy savings calculates, and value is 0,365 respectively; f _inx () is annual indoor temperature curvilinear equation; calculate by formula (21); Final building energy consumption can be expressed as formula (24):

$S^{\&prime;}=\frac{b-a}{l}\underset{D=1}{\overset{l}{\mathrm{\&Sigma;}}}{y}_{D,\mathrm{in}}=\underset{D=1}{\overset{365}{\mathrm{\&Sigma;}}}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{in}}-t_{\mathrm{comf}}|=\underset{D=1}{\overset{365}{\mathrm{\&Sigma;}}}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{in}}-22|---\left(24\right)$

In formula (24), y _{d, in}be D day indoor per day natural room temperature and the difference of annual comfort temperature, DEG C; t _{d, in}be D day indoor per day natural room temperature, DEG C; t _comffor average of the whole year comfort temperature, DEG C, the present invention gets 22 DEG C;

Step 5, the building energy consumption that the reference energy consumption utilizing step 3 to calculate and step 4 calculate, calculates building according to formula (25) and regulates energy consumption Δ S:

$\mathrm{\&Delta;S}=S-S^{\&prime;}=\underset{D=1}{\overset{365}{\mathrm{\&Sigma;}}}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{out}}-22|-\underset{D=1}{\overset{365}{\mathrm{\&Sigma;}}}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{in}}-22|---\left(25\right)$

Step 6, according to the building energy saving rate Computing Principle that the present invention proposes, calculates building energy saving rate J by formula (26):

$J=\frac{\mathrm{\&Delta;S}}{S}\&times;100\%=\frac{{\mathrm{\&Sigma;}}_{D=1}^{365}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{out}}-22|-{\mathrm{\&Sigma;}}_{D=1}^{365}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{in}}-22|}{{\mathrm{\&Sigma;}}_{D=1}^{365}|{\stackrel{\&OverBar;}{t}}_{D,\mathrm{out}}-22|}\&times;100\%---\left(26\right)$

Step 7, according to the design standard for energy efficiency of buildings of building design office foundation, building and building enclosure Thermal Design parameter are according to energy-saving design parameter limit value value each in standard, all the other optimum configurations and J must be consistent when calculating, Criterion model (namely above-mentioned computation process adopt be the design parameter obtained from design drawing, handbook, be the fractional energy savings of the BUILDINGS MODELS of calculating one " virtual " in computation process; And master pattern is the realistic model set up with this design parameter, the actual parameter measured in realistic model is to calculate the fractional energy savings of realistic model), the new building energy saving rate J of the present invention's proposition corresponding to master pattern is calculated according to step one to the method that step 6 is identical ₀; Namely the computation model of J is that each design parameter limit value specified in energy saving igniter according to architectural design foundation is set up, J ₀computation model be according to reality building design drawing and design parameter set up.

Step 8, the J that comparison step seven obtains ₀with the J that step 6 obtains, if J>J ₀, then judge that this architectural design meets the requirement of existing energy saving igniter; If J<J ₀, so architect can under the prerequisite substantially not changing design original intention, by changing certain (or some) design parameter of building and building enclosure Thermal Design, by step 2 to step 6 cycle calculations, until J>J ₀, also namely this Building Design meets the requirement of existing energy saving igniter.

Embodiment:

Be described according to the computation process of the inventive method for a virtual building below.

Example building is defined as individual layer residential architecture, and be positioned at Xi'an region, carry out energy-saving design according to national act.std " severe cold and cold district energy Saving Design of Residential Buildings standard " JGJ26-2010, architectural exterior-protecting construction parameters all gets the limit value of this standard-required.This model is simplified model, only arranges the peripheral structure contacted with outdoor climate, without partition wall and other structures in building.Master pattern basic parameter and calculating parameter value table when table 1 and table 2 are calculating, as shown in Figure 4, exterior wall and roofing specifically construct as shown in Figure 5 and Figure 6, and in Fig. 5 and Fig. 6,1 is polymer mortar, 20mm for architectural plane and concrete size; 2 is clay solid brick, 240mm; 3 is sand-cement slurry, 20mm; 4 is EPS plate, 85mm; 5 is sand-cement slurry, 20mm; 6 is reinforced concrete, 100mm; 7 is boiler slag, 60mm; 8 is expansion polyphenyl plate, 90mm; 9 is haydite, 150mm; 10 is C15 concrete, 30mm; 11 is water barrier, 10mm.

Table 1 master pattern building enclosure basic parameter value table

Table 2 master pattern fractional energy savings calculating parameter value table

According to parameters value in table 1 and table 2, utilize said method calculate indoor day by time natural room temperature, and then per day natural room temperature can be obtained.For obtaining the energy-efficient performance of buildings itself, carrying out indoor during calculating and arranging without thermal source, and in annual natural running status.By the per day outside air temperature of the whole year with per day indoor air temperature generate annual outdoor temperature curve f respectively _out(x) and annual indoor temperature curve f _inx (), sees Fig. 5; Formula (22) and formula (24) is utilized to calculate two curves and average of the whole year confort line (f respectively _comf(x)=22 DEG C) area S and S ' that enclose, be reference energy consumption and building energy consumption.By calculating, S and S ' is respectively 3725.96,3136.71, can calculate building and regulate energy consumption Δ S to be 589.25, finally can calculate master pattern building energy saving rate J according to formula (26) by formula (25) ₀be 15.8%.

Above-mentioned computation process is the master pattern building energy saving rate J calculated according to the inventive method according to design drawing and every design parameter of buildings ₀, and according to this Building Design drawing build actual buildings, according to its every actual measurement parameter, utilize said method, can calculate equally actual buildings fractional energy savings J, compare J and J ₀if, J>J ₀, then judge that this Building Design meets the requirement of existing energy saving igniter; If J<J ₀, so architect can under the prerequisite substantially not changing design original intention, and by the architectural design parameter related in change table 1 or table 2, re-start calculating, calculation process is shown in Fig. 8, finally works as J>J ₀, so can judge that this Building Design meets the requirement of existing energy saving igniter, also maintain architect's design style originally simultaneously.

For making computation process of the present invention simple and clear and concrete operation method being described, the present embodiment constructs one and simplifies building, only comprises single space.When carrying out the calculating of fractional energy savings to reality building according to the present invention, computation model can be set up according to actual building design drawing, and according to the classification that reality is built, the energy saving igniter of function and institute's foundation carries out the optimum configurations of being correlated with, and according to above-mentioned calculating desired parameters and computation process, write natural room temperature calculation procedure, on the basis obtaining outdoor instant time temperature every day and all calculating parameters, utilize this program computability go out indoor every day by time natural temperature, according to above-mentioned formula (22), formula (24), formula (25) and formula (26), finally can draw fractional energy savings.It should be noted that, the annual indoor air temperature daily mean calculated should be the mean value of each compartment temperature.

Can say, this new fractional energy savings computing method are a kind of trials completely newly, but this method is as a kind of instrument, consider topmost influence factor (air themperature), calculation procedure is clear and definite, relate to architectural exterior-protecting construction design parameter comprehensive, be applicable to very much the initial stage decision-making of architectural design.This method is applicable to the calculating of all regions different kinds of building fractional energy savings, simply, exactly the energy-efficient performance of buildings self can be passed judgment on by unified standard, and architect can be helped to compare different designs scheme, revise or optimize original design proposal, architect is encouraged to give full play to the design ability of oneself, create more unique styles and there is the building of good energy-efficient performance, passing on China's regional architectural culture better.

Claims (2)

1. Saving In Buildings energy rate computing method, is characterized in that, comprise the following steps:

Step one, obtains buildings and plans to build the annual every per day outside air temperature in ground

Step 2, obtain the per day natural room temperature of buildings, concrete steps comprise:

Building envelope being carried out layering by material, exterior wall and roofing are divided into n layer, m layer respectively, all successively increasing progressively according to arriving outdoor direction indoor;

Set up indoor air temperature node thermal balance model:

$\begin{array}{c}{\mathrm{C\&rho;}}_{\mathrm{in}}V\frac{{\mathrm{dt}}_{D,i,\mathrm{in}}}{\mathrm{d\&tau;}}=k_{w,\mathrm{in}}{F}_w(t_{w,1}-t_{D,i,\mathrm{in}})+k_{r,\mathrm{in}}{F}_r(t_{r,1}-t_{D,i,\mathrm{in}})+\\ (t_{D,i,\mathrm{out}}-t_{D,i,\mathrm{in}})({\mathrm{C\&rho;}}_{\mathrm{out}}\mathrm{VN}/3600+F_C\&CenterDot;k_C)+Q_C\end{array}---\left(1\right)$

In formula (1), C is the specific heat of air, ρ _infor the density of room air, V is room volume, t _{d, i, in}, t _{d, i, out}be respectively moment D day i-th indoor, outside air temperature, τ is the time, k _{w, in}, k _{r, in}be respectively the heat transfer coefficient between room air and the 1st layer of exterior wall, roofing, F _w, F _wbe respectively the area of exterior wall, roofing, t _{w, 1}, t _{r, 1}be respectively be the 1st layer of outer wall material, the 1st layer of roofing in the temperature in moment D day i-th, ρ _outfor the density of outdoor air, N is rate of ventilation, F _cfor outer window ara, k _cfor the heat transfer coefficient of window, Q _cfor being obtained the indoor hourly cooling load that heat causes by window insolation;

Solve formula (1), obtain buildings D day i-th moment indoor temperature t _{d, i, in}, then obtain the annual average indoor temperature of buildings

Step 3, according to every per day outside air temperature whole year that step one obtains generate annual outdoor temperature curve f _out(x), in the coordinate axis of temperature curve, x-axis is the time, and y-axis is temperature; Accounting temperature curve f _outx area S that () and average of the whole year confort line enclose;

Step 4, according to the indoor per day natural room temperature whole year that step 2 obtains generate annual indoor temperature curve f _inx (), calculates f _inx area S ' that () and annual confort line enclose;

Step 5, calculates building and regulates energy consumption: Δ S=S-S ';

Step 6, calculates building energy saving rate J:

$J=\frac{\mathrm{\&Delta;S}}{S}\&times;100\%$

Step 7, according to the design standard for energy efficiency of buildings of building design office foundation, building and building enclosure Thermal Design parameter according to energy-saving design parameter limit value value each in standard, set up actual standard model, calculate building energy saving rate J corresponding to master pattern according to step one to the method that step 6 is identical ₀;

Step 8, the J that comparison step seven obtains ₀with the J that step 6 obtains, if J>J ₀, then judge that this architectural design meets the requirement of existing energy saving igniter; If J<J ₀, so architect can change the design parameter of building and building enclosure Thermal Design, by step 2 to step 6 cycle calculations, until J>J ₀.

2. described Saving In Buildings energy rate computing method as claimed in claim 1, it is characterized in that, the solution procedure of indoor air temperature node thermal balance equation comprises:

In every one deck of exterior wall and roofing, choose temperature nodes, set up the thermal balance equation of exterior wall and roofing:

Exterior wall xth (x=1,2 ..., n) thermal balance equation of layer temperature nodes is:

Roofing y (y=1,2 ..., m) thermal balance equation of layer temperature nodes is:

Formula (2) is in formula (7): C _w,xand C _r,yfor the specific heat of exterior wall and the every layer material of roofing, δ _w,x, δ _r,ybe respectively the thickness of exterior wall, the every layer material of roofing, ρ _w,x, ρ _r,ybe respectively the density of exterior wall, the every layer material of roofing, t _w,x, t _r,ybe respectively the temperature for temperature nodes in xth layer outer wall material, y layer roofing, k _w,x, k _r,ybe respectively xth layer and (x+1)th layer exterior wall, heat transfer coefficient between y layer and y+1 layer roofing, k _{w, out}, k _{r, out}be respectively exterior wall n-th layer, heat transfer coefficient between roofing m layer and outdoor air, t _safor outdoor air integrated temperature;

Wherein:

$k_{w,\mathrm{in}}=\frac{1}{\frac{1}{{\mathrm{\&alpha;}}_1}+\frac{{\mathrm{\&delta;}}_{w,1}}{{2\mathrm{\&lambda;}}_{w,1}}}---\left(8\right)$

$k_{w,x}=\frac{1}{\frac{{\mathrm{\&delta;}}_{w,x}}{{2\mathrm{\&lambda;}}_{w,x}}+\frac{{\mathrm{\&delta;}}_{w,x+1}}{{2\mathrm{\&lambda;}}_{w,x+1}}}---\left(9\right)$

$k_{w,\mathrm{out}}=\frac{1}{\frac{1}{{\mathrm{\&alpha;}}_2}+\frac{{\mathrm{\&delta;}}_{w,n}}{{2\mathrm{\&lambda;}}_{w,n}}}---\left(10\right)$

Formula (8) in formula (10), α ₁for the convection transfer rate between room air and the 1st layer of exterior wall, δ _{w, 1}be the thickness of the 1st layer of outer wall material, λ _{w, 1}be the coefficient of heat conductivity of the 1st layer of outer wall material, α ₂for the convection transfer rate between n-th layer exterior wall and outdoor air;

Subscript w in formula (8), formula (9) and formula (10) is replaced with subscript r, and subscript x replaces with subscript y, and subscript m replaces subscript n, and formula is constant, then obtain the k of roofing _{r, in}, k _r,yand k _{r, out};

T in formula (4) _safor:

$t_{\mathrm{sa}}=t_{D,i,\mathrm{out}}+\frac{{\mathrm{\&rho;}}_{s}I}{{\mathrm{\&alpha;}}_3}---\left(11\right)$

In formula (11), ρ _sfor solar radiation absorbility factor; α ₃for outside surface convection transfer rate;

Q in formula (1) _cfor:

Q _C＝F _C·X _g·X _d·J _wτ(12)

In formula (12), X _gfor the structure correction factor of window; X _dfor place correction factor; J _{w τ}for inscribing through the refrigeration duty intensity without the radiation of sunshading facility glass solar when calculating;

Association type (2) solves formula (1) to formula (12), can obtain buildings D day i moment natural room temperature t _{d, i, in}; The indoor temperature in the whole year of trying to achieve in each moment is averaged, obtains the annual average indoor temperature of buildings