Air volume adjusting method for ship constant air volume air conditioning system

Abstract

The invention discloses an air volume adjusting method and system for a ship constant air volume air conditioning system. The method comprises the steps that the opening degree of a valve on an air pipe is adjusted to be maximum; the sum of the actual maximum air volume discharged to all the cabins by the air conditioner is obtained; acquiring the total required air volume of the ship cabin; calculating the ratio of the total demand air volume of the ship cabin to the sum of the actual maximum air volume; the function relation between the valve opening degree of an air pipe where the air distributor is located and the exhaust air rate of the air distributor is obtained; the total opening degree of an equivalent pipeline is obtained; solving a relational expression between the opening degree of the valve on each air pipe and the total opening degree of the equivalent pipeline; calculating to obtain a relational expression between the opening degree of the valve on each air pipe and the required air volume of the air distributor at the tail end of the air pipe, and substituting the relational expression into the air distributor to obtain the required air volume to obtain the opening degree of the valve on the air pipe; and adjusting the valve opening. The system comprises a data acquisition module, an air volume demand calculation module, a valve opening calculation module and an adjustment module. The air volume balance problem of the ship constant air volume air conditioning system can be solved, and the cabin environment temperature is effectively controlled.

Description

Technical Field

[0001] This invention relates to the field of marine air conditioning commissioning technology, and in particular to a method for adjusting the air volume of a marine constant air volume air conditioning system. Background Technology

[0002] Due to the compact layout of ship cabins and limited space for duct installation, ships experience wind, waves, tilting and vibration during navigation. Most existing ships use constant air volume air conditioning systems, which have simple duct design, simple mechanical structure, strong anti-interference ability and low failure rate.

[0003] Existing shipboard constant volume air conditioning systems have the following main problems in terms of air volume balance:

[0004] First, the system relies on the air distributors at the end of the compartments and the dampers in the ducts to regulate the air volume. However, due to the connectivity of the duct network, adjusting the opening of the damper in one compartment will interfere with the air volume distribution in other compartments, causing the overall balance to be disrupted and making it difficult to achieve precise control.

[0005] Secondly, the current air volume adjustment mainly relies on repeated adjustments based on human experience, which is not only time-consuming and labor-intensive, but also difficult to achieve the ideal air volume distribution effect. During the adjustment process, some air distributors may generate excessive resistance due to improper adjustment, thereby increasing airflow noise, affecting cabin comfort, and ultimately leading to problems such as poor overall system balance and increased energy consumption.

[0006] Furthermore, during actual operation, the navigation environment (such as changes in temperature and humidity) and the thermal comfort requirements of cabin personnel may change, making the initial airflow distribution no longer applicable. If the traditional manual adjustment method is still used at this time, not only will the above problems be faced again, but the frequent adjustments may also accelerate equipment wear and further reduce system reliability.

[0007] To balance the airflow in various compartments of a ship's constant air volume (CAV) air conditioning system, existing technologies involve retrofitting the existing system, but this is extremely costly. How to adjust the airflow of the ship's CAV air conditioning system accurately and cost-effectively to achieve airflow balance in each compartment is a pressing issue that needs to be addressed in the ship's air conditioning development. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this application provides a method and system for adjusting air volume in a ship's constant air volume air conditioning system, thereby solving the technical problems of difficulty in achieving precise air volume control and time-consuming and labor-intensive air volume control in existing ship constant air volume air conditioning systems.

[0009] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0010] A method for regulating air volume in a ship's constant air volume air conditioning system, the ship's constant air volume air conditioning system including an indirect air conditioner and multiple air distributors, the air distributors being connected to the indirect air conditioner via ducts, and valves being installed on the ducts to control the air volume of the air distributors;

[0011] The air volume adjustment method includes the following steps:

[0012] Step 1: Adjust the valve on the air duct to its maximum opening;

[0013] Step 2: Measure the exhaust volume Q1, Q2, Q3, ..., Q of each air distributor at the end of each duct branch with the valves at their maximum opening. n Calculate the sum of the actual maximum air volume discharged by the air conditioner to each compartment when the valve is at its maximum opening. Where i is the serial number of the air distributor and n is the number of air distributors;

[0014] Step 3: Obtain the required air volume q1, q2, q3, ..., q for each air distributor. n Calculate the total required air volume for ship cabins

[0015] Step 4: Calculate the ratio of the total required air volume for the ship's cabins to the sum of the actual maximum air volume.

[0016]

[0017] Step 5: Obtain the functional relationship between the valve opening degree of the duct where the air distributor is located and the air distributor's exhaust volume.

[0018] Step 6: Substitute the formula into Step 5. The inverse function can be used to calculate the equivalent total pipe opening ε. 总

[0019]

[0020] Step 7, the equivalent total duct opening ε of the ship's constant air volume air conditioning system. 总 With the valve opening ε on each air duct i and the diameter of the air duct in front of each air distributor The relationship is given by Formula 3:

[0021]

[0022] Valve opening ε on each air duct i The proportional relationship is given by Formula 4:

[0023]

[0024] The valve opening ε on each duct is calculated using formulas 3 and 4. i With equivalent total pipe opening ε 总 Relationship:

[0025]

[0026] Step 8: Substitute Formula 1 and Formula 2 into Formula 5 to obtain the valve opening ε on each duct. i The relationship between the required air volume and the air distributor at the end of the duct is given by Formula Six:

[0027]

[0028] Step 9: Input the required air volume of the air distributor at the end of the duct into Formula 6, and adjust the valve opening on each duct according to the calculation results.

[0029] In one implementation, the required air volume q for each air distributor in step 3 i The number of people inside and outside the cabin is determined based on the temperature difference between the cabin and the outside.

[0030] In one implementation scheme, the required air volume q for each air distributor is... i Calculate according to Formula 7:

[0031] q i (δt,n p ,)=175δt+220n p +500 Formula Seven

[0032] Where δt is the temperature difference between the inside and outside of the cabin, n p This refers to the number of people in the cabin.

[0033] In one embodiment, the duct is equipped with valves including a duct damper installed outside the cabin and a distributor damper installed inside the cabin. In step 9, the total opening of the duct damper and the distributor damper is adjusted according to the calculation results.

[0034] In one implementation, in step 9, the opening of the air distributor damper is adjusted to the maximum, and the opening of the duct damper is adjusted according to the calculation results.

[0035] In one implementation, the diameter of the ventilation ducts connecting each air distributor is the same, and formula six in step 8 can be simplified to formula eight.

[0036]

[0037] This application also provides an air volume regulation system for a ship's constant air volume air conditioning system. The ship's constant air volume air conditioning system includes an indirect air conditioner and parallel-connected air ducts. One end of the air duct is connected to the indirect air conditioner, and the other end of the air duct is equipped with an air distributor. Each air duct is equipped with a valve to control the air volume of the air distributor. The air volume regulation system includes a data acquisition module, an air volume demand calculation module, a valve opening calculation module, and an adjustment module.

[0038] The data acquisition module is used to collect the temperature difference δt between the inside and outside of the cabin and the number of people inside the cabin, n. p ;

[0039] The air volume demand calculation module is based on the temperature difference δt between the inside and outside of the cabin and the number of people in the cabin n. p Calculate the required air volume q for each air distributor. i ;

[0040] The valve opening calculation module calculates the sum of the actual maximum air volume Q discharged by the air conditioner to each compartment when the valve opening is at its maximum. MAX Total required air volume q for ship cabins 总 Calculate the valve opening based on the functional relationship between valve opening and air distributor exhaust volume;

[0041] The adjustment module adjusts the opening degree of each valve according to the calculation results of the valve opening degree calculation module.

[0042] In one embodiment, the calculation method of the valve opening calculation module includes the following steps:

[0043] Step 1: Adjust the opening of each duct to its maximum.

[0044] Step 2: Measure the exhaust volume Q1, Q2, Q3, ..., Q of each air distributor at the end of each duct branch with the valves at their maximum opening. n Calculate the sum of the actual maximum air volume discharged by the air conditioner to each compartment when the valve is at its maximum opening. Where i is the serial number of the air distributor and n is the number of air distributors on the ship;

[0045] Step 3: Obtain the required air volume q1, q2, q3, ..., q for each air distributor. n Calculate the total required air volume for ship cabins

[0046] Step 4: Calculate the ratio of the total required air volume for the ship's cabins to the sum of the actual maximum air volume.

[0047]

[0048] Step 5: Obtain the functional relationship between valve opening and air distributor exhaust volume.

[0049] Step 6: Substitute the formula into Step 5. The inverse function can be used to calculate the equivalent total pipe opening ε. 总

[0050]

[0051] Step 7, the equivalent total duct opening ε of the ship's constant air volume air conditioning system. 总 With the valve opening ε on each air duct i and the diameter of the air duct in front of each air distributor The relationship is given by Formula 3:

[0052]

[0053] Valve opening ε on each air duct i The proportional relationship is given by Formula 4:

[0054]

[0055] The valve opening ε on each duct is calculated using formulas 3 and 4. i With equivalent total pipe opening ε 总 Relationship:

[0056]

[0057] Step 8: Substitute Formula 1 and Formula 2 into Formula 5 to obtain the valve opening ε on each duct. i The relationship between the required air volume and the air distributor at the end of the duct is given by Formula Six:

[0058]

[0059] Compared with the prior art, this application has at least the following beneficial effects:

[0060] The air volume adjustment method and system for a ship's constant volume air conditioning system disclosed in this application are based on the temperature difference δt between the inside and outside of the cabin and the number of people in the cabin n. p Calculate the required air volume for each air distributor, and then calculate the sum of the actual maximum air volume Q discharged by the air conditioner to each compartment when the valve is at its maximum opening. MAX Total required air volume q for ship cabins 总 The valve opening is calculated using the functional relationship between valve opening and air distributor exhaust volume. Based on the existing ship constant air volume air conditioning system, the required opening of each compartment can be quickly calculated according to actual needs without affecting the air volume of other compartments. This solves the air volume balance problem of ship constant air volume air conditioning system, significantly reduces valve commissioning time, and effectively controls the ambient temperature of the compartment within the normal operating range. Attached Figure Description

[0061] Figure 1 This is a schematic diagram of the air volume regulation system of the ship's constant air volume air conditioning system in Embodiment 1 of this application;

[0062] Figure 2 This is a schematic diagram of the air volume regulation system of the ship's constant air volume air conditioning system in Embodiment 2 of this application.

[0063] Attached reference numerals: 1. Indirect air conditioner; 2. Air duct; 3. Air duct damper; 4. Air distributor; 5. Air distributor damper. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0065] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0066] It should be understood that although the terms first, second, third, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms and should not be construed as indicating or implying relative importance. These terms are used only to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0067] In the description of this invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical connection or internal connection between two components. They can be direct connection or indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0068] To better understand the technical solution of the present invention, the present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0069] Example 1

[0070] This embodiment provides a method for regulating airflow balance in a ship's constant air volume (CAV) air conditioning system, such as... Figure 1 As shown, the system includes an indirect air conditioner 1 and three parallel air distributors 4. The air distributors 4 are connected to the indirect air conditioner 1 via ducts 2. The air distributors 4 are installed inside the cabin. Each duct is equipped with a valve to control the airflow of the air distributor. In this embodiment, the valves include duct dampers 3 and air distributor dampers 5. The duct dampers 3 are located outside the cabin, and the air distributor dampers 5 are located inside the cabin. The specific steps include:

[0071] Step 1: Open the duct damper 3 and the air distributor damper 5, and adjust the opening of the duct damper 3 and the air distributor damper 5 to the maximum.

[0072] Step 2: Measure the air volume of the air distributors at the end of each duct branch with the valves at their maximum opening: Q1 = 500, Q2 = 400, Q3 = 600. Calculate the actual maximum air volume with the valves at their maximum opening. Air volume unit m 3 / h.

[0073] Step 3: Obtain the required air volume for each air distributor q1 = 350, q2 = 280, q3 = 400, and calculate the total required air volume. Air volume unit m 3 / h.

[0074] Step 4: Calculate the total required air volume q in S3 总 Compared with the actual maximum air volume Q in step two MAX ratio

[0075]

[0076] Step 5: Obtain the functional relationship between the valve opening degree of the duct where the air distributor is located and the air distributor's exhaust volume. This relational function can be provided by the air distributor manufacturer.

[0077] Step Six: [The text appears to be incomplete and contains several errors. A more accurate translation would require the full context.] Substitute into step five The inverse function can be used to calculate the equivalent total pipe opening.

[0078] Step 7: According to the formula and and the same front duct diameter D for each air distributor i = constant C, according to the formula Determine the valve opening of each air distributor:

[0079]

[0080] The opening degree of the air regulating damper of each air distributor is the total opening degree of the air regulating damper on the air duct where the air distributor is located and the air regulating damper of the air distributor.

[0081] The table below shows the correspondence between valve opening degree and required air volume in each compartment, calculated according to step seven.

[0082] Table 1:

[0083] Cabin name Actual maximum air volume Demand air volume Opening Cabin 1 500 350 0.32 Cabin 2 400 280 0.32 Cabin 3 600 400 0.31

[0084] Step 8: Adjust the valve openings on each duct according to the calculation results in Step 7. Alternatively, adjust the valve openings on each duct according to the corresponding table. When adjusting the valve openings on the ducts, the total opening of the duct damper and the air distributor damper must be adjusted to the calculated valve opening. To reduce cabin noise caused by valve adjustments, in this embodiment, in Step 8, the opening of the air distributor damper 5 is adjusted to the maximum, and the opening of the duct damper 3 is adjusted according to the calculation results in Step 7.

[0085] The required air volume q for each air distributor in this embodiment i Press q i (δt,n p ,)=175δt+220n p The calculation is performed using +500, where δt is the temperature difference between the inside and outside of the cabin, and n p This refers to the number of people in the cabin.

[0086] The formula derivation process in this embodiment is as follows:

[0087] When adjusting the airflow, for example, if only compartment 1 needs a reduced airflow, theoretically, reducing the damper of compartment 1 would increase the resistance of the entire duct network (increased static pressure in the ductwork; according to the fan flow-pressure curve, increased pressure leads to decreased flow), thus reducing the total airflow of the indirect constant air volume air conditioner. However, in reality, the increased resistance caused by reducing the damper of compartment 1 is very small relative to the total impedance of the entire duct network; the reduction in total airflow is far less than the reduction in airflow in compartment 1. Therefore, if the dampers of compartments 2 and 3 remain unchanged, the airflow in compartments 2 and 3 will increase. To reduce this squeezed-in airflow and keep the airflow in compartments 2 and 3 constant, the dampers of compartments 2 and 3 also need to be reduced accordingly. However, this adjustment also means that some airflow from compartments 2 and 3 is squeezed back into compartment 1, requiring compartment 1 to have its damper reduced again. This process is repeated until the decrease in total airflow caused by the increase in duct resistance due to the reduction in valve opening in the three compartments is exactly equal to the decrease in airflow required by compartment 1, and the valve opening relationship of the three compartments reaches a certain proportion. Only then is the adjustment operation considered complete. This operational logic is the method currently used on actual ships. Since the same indirect air conditioner with a certain airflow often serves far more than three compartments on actual ships, and often involves compartments on different decks, the commissioning personnel need to repeatedly adjust the system between compartments, which often takes a lot of time and is not enough to achieve the desired result.

[0088] This embodiment assumes that the airflow in each compartment has been adjusted before deriving the formula. What are the characteristics of the system at this point? 1.1 The first characteristic and its mathematical expression

[0089] After the airflow in each compartment has been adjusted, the first characteristic is that the change in airflow caused by the change in pipeline resistance due to the opening of the air distributor valves in each compartment should be exactly equal to the total change in airflow in each compartment. In other words, it can be equivalent to the change in the total airflow in the pipeline network caused by the change in the total opening of the pipeline network.

[0090]

[0091] After observing the changes in the system (only the distributor valve opening and air volume changed), it can be found that, assuming all distributor valve opening-to-air-volume percentage curves are the same, f = f1 (which is indeed the case, because the distributor valve structure determines the characteristic shape of this curve). Therefore, the function curve of the total valve opening in the pipeline versus the percentage of pipeline air volume can be equivalent to the function curve of the operating distributor opening-to-air-volume percentage (this is one of the two mathematical corollaries under the first characteristic):

[0092]

[0093] Thus, we can obtain ε. 总 The value of .

[0094] For example: When the air distributor valve is fully open, the total air volume is 800; after adjustment, the total air volume is 560. What is the percentage of total air volume corresponding to the equivalent total opening? That is, 560 / 800 = 0.7, therefore ε 总 =f -1 (0.7) = 0.55.

[0095] In addition, based on the principle characteristic in the first feature that only adjusts the opening of the air distributor valve in the pipeline network, the equivalent total opening ε of the pipeline is... 总 Based on its physical definition, the following relationship exists:

[0096]

[0097] For example: Suppose there are only 2 compartments with the same type of air distributor. The opening of the air distributor in compartment 1 after adjustment is 3 / 5, and the opening of the air distributor in compartment 2 after adjustment is 1 / 2. Then the equivalent total opening of the two air distributors is (3 / 5 + 1 / 2) / 2 = 0.55.

[0098] Therefore, based on the available known conditions, we can conclude that:

[0099]

[0100] 1.2 The second feature and its mathematical expression

[0101] The second characteristic: the adjustment range of the air valves in each compartment should be proportional to the change in airflow before and after adjustment. For example: Assume compartment 1 originally had an airflow of 500 and requires 200, and compartment 2 originally had an airflow of 500 and requires 300. Then the ratio of the air valve openings in the two compartments should be 2 / 5:3 / 5, or 2:3. Assume compartment 1 originally had an airflow of 500 and requires 200, and compartment 2 originally had an airflow of 400 and requires 500. Then the ratio of the air valve openings in the two compartments should be 2 / 5:5 / 4. After summarizing, we can conclude:

[0102]

[0103] 1.3 Mathematical expression of actual demand opening

[0104] Based on the two characteristics above, assuming that the air volume of each compartment has been adjusted, it is only necessary to obtain the equivalent total opening of the air distributor valve after adjustment. The proportional relationship between the opening degrees of each air distributor's damper after adjustment

[0105] This allows us to determine the actual required opening degree for each air distributor:

[0106]

[0107] make: but:

[0108]

[0109] It can be derived as follows:

[0110]

[0111] It can be found that:

[0112]

[0113] The following is about the heat load q of the cabin air conditioning system. i (δt,n p The calculation process of ,):

[0114] 1. Heat load transferred to the compartment:

[0115] q t =q1+q2+q3

[0116] In the formula:

[0117] q t The incoming heat load for each compartment, W;

[0118] q1 represents the heat load transferred to the sun-exposed deck, bulkheads, hull, and windows, in W;

[0119] q2 represents the heat load transferred to the exposed decks, bulkheads, and windows that are not exposed to direct sunlight, in W;

[0120] q3 represents the heat load transferred to the non-air-conditioned compartment, in W;

[0121] (1) Heat load is transferred from sun-exposed decks, hulls, bulkheads, and windows:

[0122] q1=h·A1(t0-t n )+h g ·A g (t0-t n )+h·A1′·Δt r +G s ·A s

[0123] In the formula:

[0124] h is the heat transfer coefficient of the corresponding insulation structure on each sun-exposed heat transfer surface, W / (m²). 2 ·K), here the value is 1.2;

[0125] A1 represents the area of ​​each sun-exposed heat transfer surface, in m². 2 The value here is 25;

[0126] A′1 represents the area of ​​each heat transfer surface after deducting only the area of ​​the glass window, in m. 2 The value here is 25;

[0127] h g Calculate the heat transfer coefficient over the area of ​​the glass window, W / m 2 ;

[0128] A g Calculate the area of ​​the glass window in meters. 2 The value here is 0;

[0129] G s Solar radiation heat transmittance of glass window, W / m 2 ;

[0130] A s For the area of ​​the glass window, m 2 The value here is 0;

[0131] t0 is the design temperature of the outside air, in °C, and is taken as 35 here;

[0132] t n The design temperature for the cabin air is ℃, and the value here is 27;

[0133] Δt r The solar radiation temperature rise on the sun-exposed surface is measured in K, where the value is 16.

[0134] (2) No heat load is transferred from sun-exposed decks, hulls, bulkheads, and windows:

[0135] q2=h·A2(t0+Δt e -t n )+h g ·A g (t0+Δt e -t n )

[0136] In the formula:

[0137] h is the heat transfer coefficient of the insulation structure on each heat transfer surface, W / (m²). 2 ·K), here the value is 1.2

[0138] A2 represents the area of ​​each heat transfer surface without direct sunlight, in m². 2 The value here is 25;

[0139] Δt e The surface temperature rise is due to diffuse reflection of sunlight, etc., K, and is taken as 2 to 3.

[0140] (3) Heat load transferred from surrounding non-air-conditioned compartments:

[0141] q3=h·A3·Δt

[0142] In the formula:

[0143] h is the heat transfer coefficient between the non-air-conditioned compartment and the insulation structure of that compartment, in W / (m²). 2 ·K), here the value is 1.2;

[0144] A3 represents the heat transfer surface area of ​​the surrounding non-air-conditioned compartments, in meters. 2 The value here is 135;

[0145] Δt is the temperature difference between adjacent non-air-conditioned compartments, in K, and here it is taken as 4;

[0146] From (1)(2)(3), we get:

[0147] q t =δt·175

[0148] In the formula:

[0149] δt is the temperature difference between the outside and inside of the cabin, K.

[0150] 2. Human heat load:

[0151]

[0152] In the formula:

[0153] q p Calculate the human body heat (in W) of the number of people in each cabin;

[0154] q ps Calculate the latent heat of human bodies, in W, for the number of people in each cabin;

[0155] q pl Calculate the sensible heat of the human body, in W, for each person in each cabin;

[0156] n p Count the number of people in each cabin;

[0157] q′ ps ,q′ pl The sensible and latent heat emitted by each person on average at the cabin design temperature, in W, are taken as 65 and 155 respectively here. 3. Lighting heat load:

[0158] q l =I w +1.25F w

[0159] In the formula:

[0160] ql Lighting heat load for each compartment, W, here taken as 100;

[0161] I w The wattage of the incandescent lamps in each cabin, in W;

[0162] F w The power of the fluorescent lamps in each compartment, in W.

[0163] 4. Heat generation of equipment inside the cabin

[0164] The calculation of heat generation from electrical and electronic equipment requires consideration of their power, operating time, and simultaneous operation factor. The heat generation of equipment within the cabin is expressed as q. e The calculation is simplified and omitted in this article, so it will not be elaborated upon further.

[0165] 5. Food heat load

[0166] The total calories, sensible calories, and latent calories of food in the cabin are expressed in terms of q. f q fs and q fL express.

[0167] 6. Total heat gain in the air-conditioned cabin:

[0168] q S =q t +q ps +q l +q e +q fs

[0169] q L =q PL +q fL

[0170] In the formula:

[0171] q S Sensible heat gain in each air-conditioned compartment, W;

[0172] q L The latent heat gain, W, is the heat gain of each air-conditioned compartment.

[0173] The total heat gain inside the cabin is the sum of the heat gain inside each air-conditioned compartment:

[0174] φ=φ s +φ L =∑q=∑q S +∑q L

[0175] In the formula:

[0176] φ s The total sensible heat gain inside the cabin, in W;

[0177] φ L The total latent heat gain inside the cabin is expressed in W.

[0178] Calculation of air supply volume for air-conditioned compartments:

[0179]

[0180] Depend on:

[0181] Q i =Q b +Q1+Q2=Q b +Q1(n)+Q2(t f ,t r )

[0182] The precise governing equations can be obtained:

[0183] Q i (δt,n p )=175δt+220n p +500

[0184] In the formula:

[0185] Q i That is, q S , where W is the total heat gain of each air-conditioned compartment.

[0186] Q b Based on the base heat load, W.

[0187] Example 2

[0188] This embodiment provides a method for regulating airflow balance in a ship's constant air volume (CAV) air conditioning system, such as... Figure 2 As shown, the system includes an indirect air conditioning unit 1 and 18 air distributors 4. The air distributors 4 are connected to the indirect air conditioning unit 1 via ducts 2. The air distributors 4 are installed inside the cabin. Each duct is equipped with a valve to control the airflow of the air distributor. In this embodiment, the valves include duct dampers 3 and air distributor dampers 5. The duct dampers 3 are located outside the cabin, and the air distributor dampers 5 are located inside the cabin. In this embodiment, the ship has 12 cabins. The specific steps include:

[0189] Step 1: Open the duct damper 3 and the air distributor damper 5, and adjust the opening of the duct damper 3 and the air distributor damper 5 to the maximum.

[0190] Step 2: Measure the air volume of the air distributor at the end of each duct branch with the valves at their maximum opening: Q1 = 263, Q2 = 270, ..., Q 18 =225, and calculate the actual maximum air volume under state S1. Air volume unit m3 / h. See Table 2 for specific parameters.

[0191] Step 3: Obtain the required air volume for each air distributor: q1 = 250, q2 = 250, ..., q 18 =220, calculate the total required air volume Air volume is measured in m³ / h. See Table 2 for detailed parameters.

[0192] Step 4: Calculate the total required air volume q in S3 总 Compared with the actual maximum air volume Q in step two MAX ratio

[0193]

[0194] Step 5: Obtain the functional relationship between the valve opening degree of the duct where the air distributor is located and the air distributor's exhaust volume.

[0195] Step Six: [The text appears to be incomplete and contains several errors. A more accurate translation would require the full context.] Substitute into step five The inverse function can be used to calculate the equivalent total pipe opening.

[0196] Step 7: According to the formula and and the same front duct diameter D for each air distributor i = constant C, according to the formula Determine the valve opening of each air distributor:

[0197]

[0198] The table below shows the correspondence between valve opening degree and required air volume in each compartment, calculated according to step seven.

[0199]

[0200]

[0201] Step 8: Adjust the valve openings on each duct according to the calculation results in Step 7. Alternatively, adjust the valve openings on each duct according to the corresponding table. When adjusting the valve openings on the ducts, the total opening of the duct damper and the air distributor damper must be adjusted to the calculated valve opening. To reduce cabin noise caused by valve adjustments, in this embodiment, in Step 8, the opening of the air distributor damper 5 is adjusted to the maximum, and the opening of the duct damper 3 is adjusted according to the calculation results in Step 7.

[0202] The required air volume q for each air distributor in this embodiment i Press q i (δt,n p,)=175δt+220n p The calculation is performed using +500, where δt is the temperature difference between the inside and outside of the cabin, and n p This refers to the number of people in the cabin.

[0203] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A method for regulating air volume in a ship's constant-volume air conditioning system, characterized in that, The ship's constant air volume air conditioning system includes an indirect air conditioner and multiple air distributors. The air distributors are connected to the indirect air conditioner through air ducts, and valves are installed on the air ducts to control the air volume of the air distributors. The air volume adjustment method includes the following steps: Step 1: Adjust the valve on the air duct to its maximum opening; Step 2: Measure the exhaust volume Q1, Q2, Q3, ..., Q of each air distributor at the end of each duct branch with the valves at their maximum opening. n Calculate the sum of the actual maximum air volume discharged by the air conditioner to each compartment when the valve is at its maximum opening. Where i is the serial number of the air distributor and n is the number of air distributors; Step 3: Obtain the required air volume q1, q2, q3, ..., q for each air distributor. n Calculate the total required air volume for ship cabins Step 4: Calculate the ratio of the total required air volume for the ship's cabins to the sum of the actual maximum air volume. Step 5: Obtain the functional relationship between the valve opening degree of the duct where the air distributor is located and the air distributor's exhaust volume. Step 6: Substitute the formula into Step 5. The inverse function can be used to calculate the equivalent total pipe opening ε. 总 Step 7, the equivalent total duct opening ε of the ship's constant air volume air conditioning system. 总 With the valve opening ε on each air duct i and the diameter of the air duct in front of each air distributor The relationship is given by Formula 3: Valve opening ε on each air duct i The proportional relationship is given by Formula 4: The valve opening ε on each duct is calculated using formulas 3 and 4. i With equivalent total pipe opening ε 总 Relationship: Step 8: Substitute Formula 1 and Formula 2 into Formula 5 to obtain the valve opening ε on each duct. i The relationship between the required air volume and the air distributor at the end of the duct is given by Formula Six: Step 9: Input the required air volume of the air distributor at the end of the duct into Formula 6, and adjust the valve opening on each duct according to the calculation results.

2. The air volume adjustment method for a ship's constant-volume air conditioning system according to claim 1, characterized in that, The required air volume q for each air distributor in step 3 i The number of people inside and outside the cabin is determined based on the temperature difference between the cabin and the outside.

3. The air volume adjustment method for a ship's constant-volume air conditioning system according to claim 2, characterized in that, The required air volume q for each air distributor i Calculate according to Formula 7: q i (δt,n p ,)=175δt+220n p +500 Formula Seven Where δt is the temperature difference between the inside and outside of the cabin, n p This refers to the number of people in the cabin.

4. The air volume adjustment method for a ship's constant-volume air conditioning system according to claim 1, characterized in that, The air duct is equipped with valves, including an air duct damper installed outside the cabin and an air distributor damper installed inside the cabin. In step 9, the total opening of the air duct damper and the air distributor damper is adjusted according to the calculation results.

5. The air volume adjustment method for a ship's constant-volume air conditioning system according to claim 4, characterized in that, In step 9, the opening of the air distributor damper is adjusted to the maximum, and the opening of the duct damper is adjusted according to the calculation results.

6. The air volume adjustment method for a ship's constant-volume air conditioning system according to claim 1, characterized in that, Since the diameter of the ventilation ducts connecting each air distributor is the same, formula six in step 8 can be simplified to formula eight.

7. An air volume regulation system for a ship's constant volume air conditioning system, characterized in that, The ship's constant air volume air conditioning system includes an indirect air conditioner and parallel-connected ducts. One end of the duct is connected to the indirect air conditioner, and the other end of the duct is equipped with an air distributor. Each duct is equipped with a valve to control the air volume of the air distributor. The air volume regulation system includes a data acquisition module, an air volume demand calculation module, a valve opening calculation module, and an adjustment module. The data acquisition module is used to collect the temperature difference δt between the inside and outside of the cabin and the number of people inside the cabin, n. p ; The air volume demand calculation module is based on the temperature difference δt between the inside and outside of the cabin and the number of people in the cabin n. p Calculate the required air volume q for each air distributor. i ; The valve opening calculation module calculates the sum of the actual maximum air volume Q discharged by the air conditioner to each compartment when the valve opening is at its maximum. MAX Total required air volume q for ship cabins 总 Calculate the valve opening based on the functional relationship between valve opening and air distributor exhaust volume; The adjustment module adjusts the opening degree of each valve according to the calculation results of the valve opening degree calculation module.

8. The air volume regulating system for a ship's constant-volume air conditioning system according to claim 7, characterized in that, The calculation method of the valve opening calculation module includes the following steps: Step 1: Adjust the opening of each duct to its maximum. Step 2: Measure the exhaust volume Q1, Q2, Q3, ..., Q of each air distributor at the end of each duct branch with the valves at their maximum opening. n Calculate the sum of the actual maximum air volume discharged by the air conditioner to each compartment when the valve is at its maximum opening. Where i is the serial number of the air distributor and n is the number of air distributors on the ship; Step 3: Obtain the required air volume q1, q2, q3, ..., q for each air distributor. n Calculate the total required air volume for ship cabins Step 4: Calculate the ratio of the total required air volume for the ship's cabins to the sum of the actual maximum air volume. Step 5: Obtain the functional relationship between valve opening and air distributor exhaust volume. Step 6: Substitute the formula into Step 5. The inverse function can be used to calculate the equivalent total pipe opening ε. 总 Step 7, the equivalent total duct opening ε of the ship's constant air volume air conditioning system. 总 With the valve opening ε on each air duct i and the diameter of the air duct in front of each air distributor The relationship is given by Formula 3: Valve opening ε on each air duct i The proportional relationship is given by Formula 4: The valve opening ε on each duct is calculated using formulas 3 and 4. i With equivalent total pipe opening ε 总 Relationship: Step 8: Substitute Formula 1 and Formula 2 into Formula 5 to obtain the valve opening ε on each duct. i The relationship between the required air volume and the air distributor at the end of the duct is given by Formula Six:

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