JPS58219344A - Calculating method of calorific value - Google Patents

Abstract

PURPOSE:To prevent a calculation error from occurring, by a method wherein a load quantity for air conditioning is obtained through a temperature of feed water in a given period of time up to the present time to be decided according to a present temperature of circulating water and a feed water quantity, in the calculation of a calorific value of an air conditioner applying a heat source apparatus, such as a refrigerator. CONSTITUTION:A detecting output Fv of a flow meter and an output theta2 of circulating water temperature sensor are applies to a calculating circuit CAL1. An output theta1 of feed water temperature sensor is stored in a memory MM according to a lapse of time through a writing circuit WR. Then, a variation in relation to the output Fv of the flow meter F of a time difference between feed water and circulating water calculated by a calculating circuit CAL2 is given to a reading out circuit RD, through which data in a given period of time up to the present is read out according to the output Fv of the flow meter F and applicable to the calculating circuit CAL1 by the reading out circuit RD. With this structure, a load quantity is calculated by the calculating circuit CAL1. With this constitution, a time difference error between the feed water and the circulating water is prevented from occurring and calculation can be performed correctly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a calorific value calculation method in an air conditioner using heat source equipment such as a refrigerator or a boiler.

Figure 1 is an instrumentation diagram when a refrigerator is used as the heat source equipment.The cold water cooled by the refrigerators R1-R3 is pumped by pumps P1-P3, and is sent through the header H1. The air is supplied to the air conditioning load AL such as the fan coil unit, and is then returned to the refrigerators R, -, -R3 via the header H2.
The refrigerators R1-R5 are equipped with a controller CON having an arithmetic circuit, etc.
The starting, stopping, and vane opening angles are controlled by this.

Also, the temperature of the water supplied from the header H1 is measured by a temperature sensor Tl.
At the same time, the amount of water supplied is detected by the flow meter F, while the temperature of the return water to the header H2 is detected by the temperature sensor T2, and the air conditioning load is calculated by the following formula based on these detection forces. In other words, the amount of heat consumed in the air conditioning load AL is determined, and the vane opening degrees of the refrigerators R1 to R3 are controlled accordingly.

Q = FV (112-al) x k −・−−(
1) Q is the amount of heat to be sought, FV is the detection power of the flowmeter F, al is the detection power of the temperature sensor Tl, θ2 is the detection power of the temperature sensor T2, and k is the heat conversion coefficient.

However, until the water supply from the header H1 returns to the header H2, there is a time difference depending on the status of the piping and air conditioning load AL. The time difference 'rc changes in inverse proportion to .

Therefore, even if the flow rate is constant, if the current feed water temperature and return water temperature are used in the calculation of equation (1), the current return water temperature does not necessarily correspond to the current feed water temperature, resulting in an error in the calculation result. It has the following drawbacks:

The present invention has the purpose of fundamentally eliminating the drawbacks of the conventional technology, by determining the air conditioning load amount using the current return water temperature and the water supply temperature a predetermined time before, which is determined according to the amount of water supply. , provides an extremely effective calorific value calculation method that eliminates errors in calculation results.

Hereinafter, the present invention will be explained in detail with reference to FIG. 3 showing an embodiment.

FIG. 3 is a block diagram of the heat calculation circuit housed in the controller CON. The detection force IFV of the flow rate i1F and the detection force θ2 of the temperature sensor T2 are directly calculated by equation (1). The detected power θl of the temperature sensor Tl, which is given to the arithmetic circuit CALI, is sequentially stored in each address of the memory MM over time via the ground circuit WR, and is also stored in the readout circuit RD. In addition, a read address is specified according to the detected power FV, and the read value is given to the arithmetic circuit CALl.

The contents of memory MM are as shown in the table below.
The contents of each address shift sequentially in accordance with the passage of time.

That is, every second that passes, the data at address AO is shifted to address AI, the data at address AI is shifted to address A2, and this is done sequentially for each address. The latest data is always stored.

3- Therefore, if the readout circuit RD specifies an address that stores data for a predetermined period of time determined according to the detected power FV, the supplied water temperature for a predetermined period of time determined according to the amount of water supplied can be read from the memo IJMM. The indicated value is read out and is used for calculation in the calculation circuit CA L 1.

Therefore, the calculation in the calculation circuit CAL is based on the current return water temperature and the feed water temperature when the current return water is fed from the header 1. The occurrence of corresponding errors is prevented.

However, since the slope of the curve shown in FIG. 2 changes depending on the conditions of the piping and air conditioning load AL, and the time point before the predetermined time corresponding to the amount of water supply also changes accordingly, the slope of the curve shown in FIG.
Signals St□ and Si2 corresponding to the 11 and t2Ω values shown in FIG. 2 are applied to AL2, and the slope of the curve is calculated at and \, and this result is applied to the readout circuit RD.

Therefore, the readout circuit RD converts the value of the detection power FV according to the value from the arithmetic circuit CALz, and then specifies the address for the 4-memory MM.

However, the same applies not only when using refrigerators R1-R3, but also when using a boiler, etc. The configuration shown in Fig. 3 can be replaced with a processor, etc. that executes a program, etc. However, the present invention is susceptible to various modifications.

As is clear from the above explanation, according to the present invention, the calculation of the amount of heat indicating the air conditioning load becomes accurate, and the control of the heat source equipment based on this also becomes accurate. Effects can be obtained.

[Brief explanation of the drawing]

Figure 1 is an instrumentation diagram when a refrigerator is used as a heat source device.
FIG. 2 is a diagram showing the time difference between water supply and water return, and FIG. 3 is a block diagram showing an embodiment of the present invention. R1-R: l... Refrigerator, P l= P 3...
-Pump, F...Flowmeter, TI, T2@...Temperature sensor, CALlr CAL2-...Arithmetic circuit, WR
・0...Writing circuit, MM-1Φ・Memory, RD@...
readout circuit. Special fraud applicant Yamani-no Newel Co., Ltd. agent
Kazuka Yamakawa (and 1 other person) = 7- Figure 1 Figure 2 c

Claims (1)

[Claims] In the heat amount calculation method for determining the air conditioning load lid based on the water supply amount, the water supply temperature, and the return water temperature, the air conditioning load is calculated using the current return water temperature and the water supply temperature a predetermined time before, which is determined according to the water supply amount. A calorific value calculation method characterized by calculating the amount.