New procedure for estimating seasonal energy efficiency ratio of chillers.ABSTRACT
This paper proposes a new index of the seasonal energy efficiency for chillers. The new index, the CSE (Certified Systems Engineer) See Microsoft certification. (chiller chill·er
1. One that chills.
2. A frightening story, especially one involving violence, evil, or the supernatural; a thriller.
1. seasonal efficiency) index, can be used by building designers for specifying the required chiller performance to manufacturers. This index has an advantage in that it is adaptable a·dapt·a·ble
Capable of adapting or of being adapted.
a·dapta·bil to multiple-chiller systems by setting six rating points to consider the difference in the COP COP
In currencies, this is the abbreviation for the Colombian Peso.
The currency market, also known as the Foreign Exchange market, is the largest financial market in the world, with a daily average volume of over US $1 trillion. due to the entering condenser condenser
Device for reducing a gas or vapour to a liquid. Condensers are used in power plants to condense exhaust steam from turbines and in refrigeration plants to condense refrigerant vapours, such as ammonia and Freons. water temperature as well as the part load. In addition, the use of the weighted harmonic mean In statistics, given a set of data,
and corresponding weights,
the weighted harmonic mean is calculated as
The seasonal energy efficiency ratio The efficiency of air conditioners are often rated by theSeasonal Energy Efficiency Ratio (SEER). The higher the SEER rating of a unit, the more energy efficient it is. The SEER rating is the Btu of cooling output during a typical cooling-season divided by the total electric energy is an important index for predicting the energy efficiency of a chiller under actual operating conditions. It is also a useful tool for building designers when specifying the required chiller performance to manufacturers. In the USA, the Air-Conditioning air-conditioning
Control of temperature, humidity, purity, and motion of air in an enclosed space, independent of outside conditions. In a self-contained air-conditioning unit, air is heated in a boiler unit or cooled by being blown across a refrigerant-filled coil and then and Refrigeration refrigeration, process for drawing heat from substances to lower their temperature, often for purposes of preservation. Refrigeration in its modern, portable form also depends on insulating materials that are thin yet effective. Institute (ARI ARI Acute respiratory infection, see there 2003) has a standard for the performance rating of water-chilling packages using the vapor vapor /va·por/ (va´por) pl. vapo´res, vapors [L.]
1. steam, gas, or exhalation.
2. an atmospheric dispersion of a substance that in its normal state is liquid or solid. compression cycle (ARI Standard 550/590). In this standard, the seasonal energy efficiency of a chiller is expressed as the integrated part-load value (IPLV IPLV Integrated Part-Load Values (rating for equipment that cools water for air conditioning)
IPLV Institut de Perfectionnement en Langues Vivantes ). IPLV is calculated from four measured coefficients of performance (COPs) at loads of 100%, 75%, 50%, and 25%. Further, in Japan, the Society of Heating, Air-Conditioning and Sanitary Engineers sanitary engineer
An engineer specializing in the maintenance of urban environmental conditions conducive to the preservation of public health.
sanitary engineering n. of Japan (SHASE) had proposed the use of the IPLV, but it has not been used commonly; rather, the COP at maximum capacity is usually used as the energy efficiency index of chillers. Since the efficiency of a chiller depends on the part-load ratio and the entering condenser water temperature (ECWT ECWT Extreme Cold Weather Tent
ECWT European Conference on Wireless Technologies ) and chillers in buildings are operated at part load during most of the operating hours, evaluation based on the seasonal energy efficiency is important for designing an energy-efficient HVAC (Heating Ventilation Air Conditioning) In the home or small office with a handful of computers, HVAC is more for human comfort than the machines. In large datacenters, a humidity-free room with a steady, cool temperature is essential for the trouble-free system.
As an index for the energy efficiency of chillers, the IPLV has some limitations:
* The IPLV is designed for the part-load performance of single-chiller systems and does not consider multiple-chiller systems. In the present ARI standard, the weight of COP at 100% load is only 0.01, but it is supposed to be much larger in multiple-chiller systems and heat storage systems.
* Since the IPLV is designed for single-chiller systems, the ECWT is supposed to increase with the part-load ratio. In other words Adv. 1. in other words - otherwise stated; "in other words, we are broke"
put differently , the cooling load is in proportion with the wet-bulb temperature Wet-bulb temperature - there are several meanings of this term:
In addition, to apply the IPLV to Japanese Japanese (jăp'ənēz`), language of uncertain origin that is spoken by more than 125 million people, most of whom live in Japan. There are also many speakers of Japanese in the Ryukyu Islands, Korea, Taiwan, parts of the United States, and buildings, the rating conditions should be modified in accordance Accordance is Bible Study Software for Macintosh developed by OakTree Software, Inc.
As well as a standalone program, it is the base software packaged by Zondervan in their Bible Study suites for Macintosh. with the Japanese weather and building characteristics.
In the first part of this paper, the annual distribution of the chiller operating conditions (part-load ratio and ECWT) of each chiller in single- and multiple-chiller systems is calculated from the cooling load data of Japanese office buildings. Using these data, the rating conditions of the chiller for estimating the seasonal energy efficiency of various multiple-chiller systems are proposed. In the second part of this paper, the shortcomings A shortcoming is a character flaw.
Shortcomings may also be:
PROCEDURE TO DEFINE THE RATING CONDITIONS OF THE CHILLER PART LOAD
In ARI's procedure to derive the IPLV formula, the following assumptions were used (ARI 2003):
* Modified ASHRAE ASHRAE American Society of Heating, Refrigerating & Air Conditioning Engineers temperature bin method for energy calculation was used.
* Weather data were a weighted average of 29 cities across the USA.
* Building types were a weighted average of all types.
* Operational hours were a weighted average of various operations.
* A weighted average of buildings with and without some form of economizer e·con·o·mize
v. e·con·o·mized, e·con·o·miz·ing, e·con·o·miz·es
1. To practice economy, as by avoiding waste or reducing expenditures.
2. was used.
* The bulk of the load profile used in the last derivation derivation, in grammar: see inflection. of the equation was again used, which assumed that 38% of the building's load was the average internal load.
* One point is predetermined pre·de·ter·mine
v. pre·de·ter·mined, pre·de·ter·min·ing, pre·de·ter·mines
1. To determine, decide, or establish in advance: to be the design point of 100% load and 29.4[degrees]C (85[degrees]F). Other points were determined by distributional analysis of MJ-hours (ton-hours).
On the other hand, we defined the part-load and ECWT conditions for the rating from the actual cooling load profile of office buildings and local weather data. From hourly cooling load data, the chiller operating condition distribution, which consists of the part-load ratio and ECWT, is calculated by simulation of the cooling plant of a single-chiller system and some representative multiple-chiller systems.
Cooling Load Data Used in This Research
The cooling load profiles of 18 office buildings are used in this survey. These data are provided from the district heating District heating (less commonly called teleheating) is a system for distributing heat generated in a centralized location for residential and commercial heating requirements. and cooling plant in Tokyo Tokyo (tō`kēō), city (1990 pop. 8,163,573), capital of Japan and of Tokyo prefecture, E central Honshu, at the head of Tokyo Bay. and were recorded from April 2002 to March 2003 (Matsushima Matsushima (mäts`shĭmä), town (1990 pop. 17,431), Miyagi prefecture, N Honshu, Japan, on Ishinomaki Bay. et al. 2005). The weather data during this period are used to calculate the wet-bulb air temperature. Figure 1 presents the duration curve of these cooling load data. In most of the buildings, the cooling load occurred throughout the year. The existence of cooling load during midnight hours is a special characteristic of these buildings, which are supplied with heat from the district heating and cooling plant. Except for this, since most of the large cities in Japan This is a list of cities in Japan.
For more information about cities in Japan see Municipality of Japan. Note that Tokyo is actually a special kind of prefecture not a city. Most large cities in Japan are cities designated by government ordinance. have the same climatic condition as Tokyo, these data are supposed to represent the cooling load profile of most of the office buildings in Japan.
[FIGURE 1 OMITTED]
Chillers Evaluated in This Study
To obtain the load of each chiller from the total building cooling load, a chiller sequence control simulation model was developed. The chillers simulated in this model are defined as follows:
* Three types of cooling plants are simulated: a single-chiller plant, a two-chiller plant, and a three-chiller plant.
* The total cooling capacity of the plant is assumed to be equal to the annual maximum cooling load of the building. In addition, every chiller in the multiple-chiller system is assumed to have the same capacity.
* Each chiller in the multiple-chiller plant is assigned as·sign
tr.v. as·signed, as·sign·ing, as·signs
1. To set apart for a particular purpose; designate: assigned a day for the inspection.
2. a particular role. In the case of the three-chiller plant (as shown in Figure 2), the base chiller is started first and operated whenever a cooling load exists. When the cooling load exceeds the capacity of the base chiller, the middle chiller is operated. When the cooling load exceeds the total capacity of these two chillers, the peak chiller is operated.
* The rotating ro·tate
v. ro·tat·ed, ro·tat·ing, ro·tates
1. To turn around on an axis or center.
2. chiller switches its role on a daily basis. For example, in the three-chiller system, the rotating chiller alternately operates as the base, middle, and peak chiller. In this case, every chiller in the plant is assumed to have the same characteristics.
[FIGURE 2 OMITTED]
* As a result, eight kinds of chillers are evaluated: The chiller in the single-chiller system (1); the base (2-b), peak (2-p), and rotating (2-r) chillers in the two-chiller system; and the base (3-b), middle (3-m), peak (3-p), and rotating (3-r) chillers in the three-chiller system.
Chiller Sequence Control Simulation
The flow of the chiller sequence control simulation is as follows:
* Based on the cooling load measured every hour, the number of operational chillers is decided. The cooling load is equally divided into the operational chillers. The chiller control sequence is indicated by the solid line (ideal case) in Figure 2.
* The ECWT is calculated from the wet-bulb temperature and the amount of exhaust heat Exhaust Heat is a Super Famicom game that simulates the season and career of a Formula One superstar. There are over a dozen courses around the world to race and all of them are likenesses of real Formula One tracks (including realistic looking advertisements where the audience from the condenser of the chiller using the cooling tower model. The exhaust heat from the chiller is the sum of the cooling load and the energy consumption of the chiller (compressor) and is a function of the chiller's COP. On the other hand, the chiller's COP is a function of the cooling load and ECWT. Therefore, the ECWT and COP of the chiller must be calculated simultaneously using the cooling tower model and chiller model, respectively. The relationship among the part load, ECWT, and COP of the turbo TURBO A clinical trial–The Ultrasound Removal of Blood Clots in Vein Grafts chiller and inverter-driven variable-speed compressor turbo chiller (inverter (1) A logic gate that converts the input to the opposite state for output. If the input is true, the output is false, and vice versa. An inverter performs the Boolean logic NOT operation.
(2) A circuit that converts DC current into AC current. Contrast with rectifier. turbo chiller) is shown in Figure 3. The relationship among the outdoor wet-bulb temperature, temperature of water entering the cooling tower, and ECWT is shown in Figure 4.
[FIGURE 3 OMITTED]
* To ensure stable operation of the chiller, most cooling plants in Japan control the speed of the cooling tower fan to maintain the ECWT above a certain value. This is the common practice in Japan, and one of the reasons is that most of the cooling plants have at least one absorption chiller that must be operated at high ECWT. Therefore, we set 22[degrees]C (71.6[degrees]F) as the minimum ECWT. This value should be reconsidered when this index is applied in other countries.
* When the part load of the chiller is less than 20%, intermittent intermittent /in·ter·mit·tent/ (-mit´ent) marked by alternating periods of activity and inactivity.
1. Stopping and starting at intervals.
2. operation at a part-load ratio of 20% is assumed.
* Repeating these calculations throughout the year, the part-load ratio, ECWT, and COP of the chiller per hour are calculated for all the chillers.
* In this simulation, each chiller's seasonal COP (SCOP scop
An Old English poet or bard.
[Old English.] ), which refers to the ratio of annual cooling load to the annual energy consumption of the chiller, is also calculated for validating val·i·date
tr.v. val·i·dat·ed, val·i·dat·ing, val·i·dates
1. To declare or make legally valid.
2. To mark with an indication of official sanction.
3. the proposed index.
Rating Points of the Chiller
Figure 5 shows the result of the chiller sequence control simulation for the base, middle, and peak chillers in the three-chiller system for one of the buildings. The characteristics of the turbo chiller, as shown in Figure 3, are used for this simulation. Each plot in these figures shows the operating part-load ratio and ECWT per hour (operating point).
In the ARI's procedure to derive the IPLV formula, these operating points are classified into four groups only by the part-load ratio. After that, the representative point (rating condition) and the duration of operation (weight) are calculated for each group. However, from Figure 5, for the base and middle load, it is clear that many operating points exist in areas where the ECWT is low and the part-load ratio is high. These points never appear in the case of the single-chiller system. Further, this area is supposed to be important when a cold-water cold-wa·ter
Lacking modern plumbing or heating facilities: a cold-water flat. storage tank is used. Therefore, we propose that each of the two higher part-load groups be divided into two groups by the ECWT to accurately express the difference in the COP of the chiller due to the ECWT.
[FIGURE 4 OMITTED]
[FIGURE 5 OMITTED]
Based on the distribution of the operating points for each chiller and building, we divided the group based on part loads of 25%, 50%, and 70% and on an ECWT of 26[degrees]C (78.8[degrees]F) to maintain a significant weight for each group of at least one type of chiller. Therefore, we defined the following six groups based on the operating conditions:
[FIGURE 6 OMITTED]
* Group 1: part-load ratio is 70%-100%, ECWT is higher than 26[degrees]C (78.8[degrees]F)
* Group 2: part-load ratio is 70%-100%, ECWT is lower than 26[degrees]C (78.8[degrees]F)
* Group 3: part-load ratio is 50%-70%, ECWT is higher than 26[degrees]C (78.8[degrees]F)
* Group 4: part-load ratio is 50%-70%, ECWT is lower than 26[degrees]C (78.8[degrees]F)
* Group 5: part-load ratio is 25%-50%
* Group 6: part-load ratio is 20%-25%
For each building and type of chiller, the part-load ratio and ECWT of the operating points in each group are averaged. The result of the averaged operating points for the cooling load profiles of 18 buildings and eight chiller types are shown in Figure 6. With the exception of a few points, the distribution of the averaged points is small. Therefore, the rating condition for each group is obtained by re-averaging these averaged operating points. The result is shown in Tables 1a and 1b. In addition, the weight of each group is calculated according to according to
1. As stated or indicated by; on the authority of: according to historians.
2. In keeping with: according to instructions.
3. the ratio of the sum of the cooling loads in each group to the annual cooling load. Table 2 shows the weight for each group and chiller type. It can be seen that each group has a weight of more than 10% for at least one type of chiller.
By rounding off the "total average" values in Table 1, we obtain the rating condition for groups 1 to 6 as shown in Table 3. Even if the characteristics of the inverter turbo chiller, as shown in Figure 3, are used, the total average values do not change. For each rating point, the COP of the chillers calculated from Figure 3 is also shown in Table 3.
DEFINITION OF THE CSE INDEX AND ITS APPLICATION
In the IPLV formula, the weighted arithmetic mean (mathematics) arithmetic mean - The mean of a list of N numbers calculated by dividing their sum by N. The arithmetic mean is appropriate for sets of numbers that are added together or that form an arithmetic series. equation is used for calculating the IPLV value from four measured COPs at loads of 100%, 75%, 50%, and 25%, as shown in Equation 1.
IPLV = 0.01A + 0.42B + 0.45C + 0.12D (1)
A = COP at 100% load and an ECWT of 29.4[degrees]C (85[degrees]F)
B = COP at 75% load and an ECWT of 23.9[degrees]C (75[degrees]F)
C = COP at 50% load and an ECWT of 18.3[degrees]C (65[degrees]F)
D = COP at 25% load and an ECWT of 12.8[degrees]C (65[degrees]F)
However, by definition,
SCOP = [annual total cooling load]/[annual total energy consumption]
= [[n.summation summation n. the final argument of an attorney at the close of a trial in which he/she attempts to convince the judge and/or jury of the virtues of the client's case. (See: closing argument) over (i = 1)] [Qc.sub.i]]/[[n.summation over (i = 1)][E.sub.i]] = [[n.summation over (i = 1)][Qc.sub.i]]/[[n.summation over (i = 1)][[Qc.sub.i]/[CO[P.sub.i]]]]=[[n.summation over (i = 1)][Qc.sub.i]]/[[6.summation over (j = 1)] ([[r.sub.j].summation over (i = 1)] [[Qc.sub.i]/[CO[P.sub.i]]])], (2)
SCOP = seasonal COP;
[Qc.sub.i] = cooling load at time i, kWh;
[E.sub.i] = energy consumption at time i, kWh;
CO[P.sub.i] = COP of the chiller at time i;
n = total duration of the chiller operation, h;
[r.sub.j] = total duration of the chiller operation in group j, h;
j = group number (j = 1 to 6).
If the difference in COP in each group is ignored and substituted by the measured value at the rating point of each group shown in Table 1, Equation 2 becomes
SCOP = [[n.summation over (i=1)][Qc.sub.i]]/[[6.summation over (j=1)]([[r.sub.j].summation over (i=1)][Qc.sub.i]]/[bar.CO[P.sub.j]]), (3)
=1/[[6.summtion over (j = 1)]([[[r.sub.j].summation over (i = 1)][Qc.sub.i]/[n.summation over (i = 1)][Qc.sub.i]]/[bar.CO[P.sub.j]])] = 1/[[6.summation over (j=1)]([W.sub.j]/[bar.CO[P.sub.j]])]
[bar.CO[P.sub.j]] = COP of the chiller measured at the rating point of group j and
[W.sub.j] = weight of group j.
Equation 3 shows that the SCOP should be estimated by the weighted harmonic mean of COPs at each rating point. To emphasize the difference between the IPLV formula and our formula, we named our formula CSE (chiller seasonal efficiency). CSE is calculated by the following equation:
CSE = 1/[[[W.sub.1]/[bar.CO[P.sub.1]]] + [[W.sub.2]/[bar.CO[P.sub.2]]] + [[W.sub.3]/[bar.CO[P.sub.3]]] + [[W.sub.4]/[bar.CO[P.sub.4]]] + [[W.sub.5]/[bar.CO[P.sub.5]]] + [[W.sub.6]/[bar.CO[P.sub.6]]]] (4)
CSE Index Under Standard Condition
Figure 7 shows the CSE index calculated using Equation 4 with the COPs of the chiller shown in Table 3 and the weights shown in Table 2 for the eight types of chillers. In addition to the conventional turbo chiller, as shown in Figure 3a, the inverter turbo chiller (variable-speed compressor), as shown in Figure 3b, is also evaluated. The COP at 100% load and the IPLV index calculated using Equation 1 are also shown in Figure 7. Since the minimum ECWT is set at 22[degrees]C (71.6[degrees]F) in this study, the COP at part loads of 25% and 50% is calculated at this temperature. Therefore, the term NPLV (non-standard part-load value) is used instead of IPLV in Figure 7. The conventional turbo chiller shows a very low CSE value in the case of the chiller types mainly operating at lower part loads. For example, CSE values of the chiller in the single-chiller plant and the base chiller in the two-chiller system are 3.68 and 4.31, respectively. The maximum difference of CSE value between the chiller types is 40%. Since the NPLV does not reflect this difference, the CSE index is advantageous.
The CSE values for the inverter turbo chiller (variable-speed compressor turbo chiller) are almost constant for all the chiller types. This means that the use of the inverter turbo chiller is effective for mainly operating at low part loads, but the advantage is small for chillers always operating at high part loads, such as peak chillers. Evaluation by the CSE index can suggest these recommendations to the HVAC designer. The NPLV value is much larger than these CSE values.
Validation See validate.
validation - The stage in the software life-cycle at the end of the development process where software is evaluated to ensure that it complies with the requirements. of CSE index
To validate To prove something to be sound or logical. Also to certify conformance to a standard. Contrast with "verify," which means to prove something to be correct.
For example, data entry validity checking determines whether the data make sense (numbers fall within a range, numeric data the superiority of the CSE based on the weighted harmonic mean of COPs in comparison to the IPLV index, three types of SCOPs are compared for a specified building (building A shown in Figure 1). The first one is the CSE index calculated from the weights calculated for building A by the chiller sequence control simulation model using Equation 4. The second one is the IPL (Initial Program Load) Same as boot.
1. IPL - Information Processing Language.
2. IPL - Internet Public Library.
3. IPL - Initial Program Load.
4. IPL - Initial Program Loader. [V.sub.six], which is the weighted arithmetic mean given by Equation 5 using the same weights and COPs as the CSE equation.
[FIGURE 7 OMITTED]
IPL[V.sub.six] = [W.sub.1] x CO[P.sub.1] + [W.sub.2] x CO[P.sub.2] + [W.sub.3] x CO[P.sub.3] + [W.sub.4] x CO[P.sub.4] + [W.sub.5] x CO[P.sub.5] + [W.sub.6] x CO[P.sub.6] (5)
The third one is the SCOP that is calculated as the ratio of annual total cooling load to annual total energy consumption (the third term of Equation 2) from the hourly cooling load and electricity consumption simulated by the chiller sequence control simulation model. This result is shown in Figure 8. The IPL[V.sub.six] index becomes larger than the simulated SCOP by approximately 10% in the case of chiller types mainly operating at low part loads. On the other hand, the CSE index shows a very good agreement with the simulated SCOP.
This result shows that the weighted arithmetic mean equation is overestimated when at least one COP is considerably lower than the other COPs. Therefore, it can be concluded that the CSE, which uses the harmonic mean har·mon·ic mean
The reciprocal of the arithmetic mean of the reciprocals of a specified set of numbers.
see harmonic mean. equation, is more accurate for estimating the SCOP of chillers.
Application of CSE to Realistic Chiller Sequence Control
For the chiller sequence control simulation used to calculate the weights shown in Table 2, the ideal situation is assumed, as indicated by the bold line in Figure 2. However, the part load of the chiller, which is actually operated in the cooling plant, is lower than the ideal situation. The reasons are as follows (Shimoda Shimoda (shĭmō`dä), town (1990 pop. 30,081), Shizuoka prefecture, E central Honshu, Japan, at the south extremity of Izu peninsula, on Shimoda Bay. It is an important port for the peninsula. The first U.S. et al. 2005):
* Usually, the total capacity of the plant is designed to be larger than the peak load by the "safety factor."
* In order to respond to a sudden increase in the cooling load and to avoid short-cycling of the chiller operation and since the temperature difference between the supply and return water is smaller than the designed value, chillers are operated such that they have a "margin of load factor."
[FIGURE 8 OMITTED]
Setting the safety factor as 20% of the peak load and the margin of load factor as 20% of the chiller capacity, the chiller sequence control is simulated for the conventional turbo chiller, as indicated by the dashed dash 1
v. dashed, dash·ing, dash·es
1. To break or smash by striking violently.
2. To hurl, knock, or thrust with sudden violence.
3. line in Figure 2, which corresponds to the actual case.
Figure 9 compares the three estimation estimation
In mathematics, use of a function or formula to derive a solution or make a prediction. Unlike approximation, it has precise connotations. In statistics, for example, it connotes the careful selection and testing of a function called an estimator. results for the eight chiller types and building A as follows:
* CSE index calculated from the standard weights shown in Table 2.
* CSE index calculated from the weights obtained by the actual chiller sequence control model for building A.
* Simulated SCOP in the case of actual chiller sequence control.
By applying the actual chiller sequence control, the SCOP decreases by about 5% for each chiller type. The CSE index calculated from the weights obtained by the actual chiller sequence control program for building A shows good agreement with the simulated SCOP. This fact suggests that if we can predict only the weights for each group, it would be possible to estimate the CSE index correctly without changing the rating points.
In this paper, a new index for estimating the seasonal energy efficiency of chillers is proposed. This index has some advantages as compared to the conventional IPLV index, as follows:
1. This index is adaptable to multiple-chiller systems by setting six rating points for considering the difference in the COP due to the ECWT.
[FIGURE 9 OMITTED]
2. The use of the weighted harmonic mean equation improves the accuracy in predicting the SCOP as compared with the weighted arithmetic mean equation adopted by the IPLV equation.
3. This index can be flexibly applied to various patterns of chiller operation by setting the weights predicted by the chiller sequence control simulation. For this purpose, a detailed simulation of the COP and heat balance of the chiller and cooling tower, respectively, is not required. Only the part load and ECWT distribution of each chiller is necessary. Therefore, this index is useful to select the optimum chiller depending on the chiller type in the cooling plant and the cooling load characteristics of the building.
To develop this index as the standard, more discussion is needed about the "standard" procedure to define the rating conditions, such as the representativity of the cooling load data, weather data, chiller control sequence, definition of the minimum ECWT, and so on.
ACKNOWLEDGMENTS See About this product.
This work was conducted under the SHASE (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) research project, "Performance Requirement Method of HVAC Equipment." The authors wish to thank the members of the project for their valuable advice.
ARI. 2003. ARI Standard 550/590-2003, Performance Rating of Water-Chilling Packages Using the Vapor Compression Cycle. Air-Conditioning and Refrigeration Institute, Arlington Arlington, county, United States
Arlington, county (1990 pop. 170,936), N Va., across the Potomac River from Washington, D.C. Arlington is a residential and commercial suburb of Washington. , VA.
Matsushima, T., T. Akiba Akiba Also pronounced Akiva can refer to:
Japanese politician who served as prime minister (1964-1972). He shared the 1974 Nobel Peace Prize for his efforts toward nuclear disarmament. , Y. Tanaka Tanaka (田中 "in the ricefield") is the 4th most common Japanese surname.
It may also refer to Tanaka Memorial an alleged Japanese war planning document. , K. Fujii. 2005. Study on building cooling and heating load database, Part 1: Prototype of building heat and chilled chill
1. A moderate but penetrating coldness.
2. A sensation of coldness, often accompanied by shivering and pallor of the skin.
3. load data sheet. Technical Papers of Annual Meeting, The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan, pp.1705-08 (in Japanese).
Shimoda, Y., T. Nagota, N. Isayama, and M. Mizuno. 2005. Verification of energy efficiency of district heating and cooling system cooling system: see air conditioning; internal-combustion engine; refrigeration.
Apparatus used to keep the temperature of a structure or device from exceeding limits imposed by needs of safety and efficiency. using realistic parameters. Proceedings of the Ninth International IBPSA IBPSA International Building Performance Simulation Association Conference, pp. 1123-30.
Yoshiyuki Shimoda, DEng
Minoru Mizuno, DEng
Yoshiyuki Shimoda is an associate professor and Minoru Mizuno is a professor in the Division of Sustainable Energy
Sustainable energy sources are energy sources which are not expected to be depleted in a timeframe relevant to the human race, and which and Environment, Osaka University Home to many elite and renowned alumni of CEOs, lawyers, doctors, scientists, bureaucrats, and a Nobel laureate, as well as to many advanced research centers, Osaka University is considered one of the most prestigious universities in Japan and Asia. , Osaka, Japan. Nattapon Choonchuachan is an engineer with Fuji Seiki seiki (sā·ē·kē),
n a form of or development from Shiatsu in which the practitioner waits until the client's energy expresses itself. Co., Ltd., and a former graduate student at Osaka University.
Table 1a. Averaged Operating Point for Each Group and Chiller Type (Load [%], ECWT [[degrees]C]) Chiller Type 1 2-b 2-p 2-r 3-b Group 1 81.2, 30.7 84.0, 29.8 80.6, 30.4 83.0, 30.1 83.5, 29.7 Group 2 79.3, 22.7 78.7, 24.4 75.6, 24.3 79.0, 24.5 80.5, 23.6 Group 3 60.1, 28.4 60.5, 28.4 60.9, 28.3 60.6, 28.4 61.4, 28.4 Group 4 53.9, 24.6 57.7, 23.3 55.7, 24.4 57.3, 23.5 57.9, 22.9 Group 5 34.7, 23.6 34.7, 22.7 --, --* 34.6, 22.7 35.6, 22.7 Group 6 20.3, 22.3 20.4, 22.3 --, -- 20.4, 22.3 21.2, 22.2 Chiller Type 3-m 3-p 3-r Total Average Group 1 82.7, 29.8 80.7, 30.4 82.7, 30.0 82.3, 30.1 Group 2 76.5, 24.7 76.1, 24.2 80.2, 23.7 78.2, 24.0 Group 3 62.1, 28.4 68.3, 29.0 62.1, 28.5 62.0, 28.5 Group 4 58.4, 23.6 68.5, 24.9 58.1, 23.0 58.4, 23.8 Group 5 --, -- --, -- 35.7, 22.7 35.1, 22.9 Group 6 --, -- --, -- 21.2, 22.2 20.7, 22.3 * "--" indicates that no operating point exists for this group and chiller type. Table 1b. Averaged Operating Point for Each Group and Chiller Type (Load [%], ECWT [[degrees]F]) Chiller Type 1 2-b 2-p 2-r 3-b Group 1 81.2, 87.3 84.0, 85.6 80.6, 86.7 83.0, 86.2 83.5, 85.5 Group 2 79.3, 72.9 78.7, 75.9 75.6, 75.7 79.0, 76.1 80.5, 74.5 Group 3 60.1, 83.1 60.5, 83.1 60.9, 82.9 60.6, 83.1 61.4, 83.1 Group 4 53.9, 76.3 57.7, 73.9 55.7, 75.9 57.3, 74.3 57.9, 73.2 Group 5 34.7, 74.5 34.7, 72.9 --, --* 34.6, 72.9 35.6, 72.9 Group 6 20.3, 72.1 20.4, 72.1 --, -- 20.4, 72.1 21.2, 72.0 Chiller Type 3-m 3-p 3-r Total Average Group 1 82.7, 85.6 80.7, 86.7 82.7, 86.0 82.3, 86.2 Group 2 76.5, 76.5 76.1, 75.6 80.2, 74.7 78.2, 75.2 Group 3 62.1, 83.1 68.3, 84.2 62.1, 83.3 62.0, 83.3 Group 4 58.4, 74.5 68.5, 76.8 58.1, 73.4 58.4, 74.8 Group 5 --, -- --, -- 35.7, 72.9 35.1, 73.2 Group 6 --, -- --, -- 21.2, 72.0 20.7, 72.1 * "--" indicates that no operating point exists for this group and chiller type. Table 2. Calculated Weights for Each Group and Chiller Type Chiller Type 1 2-b 2-p 2-r 3-b 3-m 3-p 3-r Group 1 0.19 0.24 0.55 0.29 0.24 0.58 0.87 0.35 Group 2 0.00 0.06 0.01 0.06 0.12 0.06 0.01 0.11 Group 3 0.11 0.09 0.31 0.13 0.06 0.14 0.11 0.09 Group 4 0.04 0.13 0.13 0.13 0.19 0.21 0.00 0.18 Group 5 0.26 0.23 0.00 0.20 0.19 0.00 0.00 0.14 Group 6 0.40 0.24 0.00 0.20 0.19 0.00 0.00 0.13 Table 3. Proposed Rating Condition and COP of the Chiller ECWT [[degrees]C] COP (Turbo COP (Inverter Group Part load [%] ([[degrees]F]) Chiller) Turbo Chiller) Group 1 80.0 30.0 (86.0) 6.09 6.39 Group 2 80.0 24.0 (75.2) 6.96 8.45 Group 3 60.0 28.5 (83.3) 5.69 6.29 Group 4 60.0 24.0 (75.2) 6.39 8.50 Group 5 35.0 23.0 (73.4) 4.54 7.06 Group 6 20.0 22.5 (72.5) 2.54 5.29 Full load 100.0 32.0 (89.6) 5.92 5.65