Method for arranging living building and chimney

Abstract

The invention relates to the technical field of ship overall arrangement, and discloses a living building and chimney arrangement method which comprises the following steps: step 1, simulating turbulence intensity distribution of a flow field around a chimney to obtain turbulence intensity distribution of the flow field; 2, drawing a curve graph of the maximum turbulence kinetic energy kappa of the flow field and the change of the kinetic energy E of the fluid medium under the condition that the spacing ratio gamma of the distance from different chimneys to the living building to the characteristic length of the chimney in the flow field is, selecting a natural logarithm lnE of which E is equal to 0.5 rho v2 as an axis and a turbulence intensity peak value kappa as another axis, obtaining a change curve of turbulence intensity with different gamma values along with wind kinetic energy; and 3, selecting a gamma curve characteristic value with relatively small turbulence energy as a principle for optimizing the arrangement method of the living building and the chimney. The device can simply and effectively simulate the accumulation concentration of the flue gas discharged by the chimney, so that the chimney and the living building are arranged, accumulation of chimney tail gas near the living building can be effectively reduced, and the problem that the living building area is affected by the tail gas discharged by the chimney is effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of ship overall arrangement, and in particular to a method for arranging a living building and a chimney. Background Art

[0002] Existing ships generally arrange the chimney near the living building. The length of the living building in the normal direction where the chimney and the living building are connected is longer than the length of the chimney in this direction. The chimney is arranged near the living building, and the height of the chimney exhaust port is within the height range of the living building. However, the top of the chimney is very close to the driving deck windows and the radar mast structure of the living building, which causes the chimney wake to blow towards the living building, causing the driving deck windows to be smoked and important equipment to be affected by high-temperature smoke.

[0003] Therefore, the main problem of current ships is that chimney exhaust gas has a serious impact on the living building. There is not only a lack of effective analysis methods, but also a lack of specific and feasible optimization layout plans. Summary of the invention

[0004] The technical problem to be solved by the present invention is that the distance between the chimney and the living building of the ship is relatively close, and the living building is easily affected by the smoke emitted by the chimney.

[0005] In order to solve the above technical problems, the technical solution of the present invention is to provide a method for arranging living buildings and chimneys. First, the flow field of the chimney and the living building is simulated by CFD software, and then the reasonable distribution of the chimney and the living building is guided by the simulation results, wherein the concentration of smoke diffusion is characterized by the turbulence intensity index of the fluid medium in the flow field. The arrangement method includes the following steps:

[0006] Step 1: Simulate the turbulence intensity distribution of the flow field around the chimney to obtain the turbulence intensity distribution of the flow field;

[0007] Step 2: Draw a curve of the maximum turbulent kinetic energy κ of the flow field and the kinetic energy E of the fluid medium under the conditions of different distances from the chimney to the living building and the spacing ratio γ of the characteristic length of the chimney in the flow field, and select E = 0.5ρν 2 The natural logarithm lnE is taken as one axis, and the peak value of turbulence intensity κ is taken as the other axis, and the curve of turbulence intensity changing with wind kinetic energy for different γ values ​​is obtained;

[0008] Step 3: In the curve obtained in step 2, select the characteristic value of the γ curve with smaller turbulent kinetic energy as the principle for optimizing the layout of living buildings and chimneys.

[0009] Optionally, in step three, when γ is between 0.4 and 0.45, a relatively good optimization effect is achieved, and when γ is 0.45, the best optimization effect is achieved.

[0010] Optionally, the concentration of smoke diffusion is characterized by the turbulence intensity index of the fluid medium in the flow field. In the turbulence intensity distribution obtained in step one, the greater the turbulence intensity, the greater the negative pressure formed in the flow field, the easier it is to form accumulated smoke, and the greater the smoke concentration. The smaller the turbulence intensity, the lower the flow field streamline gradient, the easier it is for the smoke to diffuse, and the smaller the smoke concentration.

[0011] Optionally, in step 2, the characteristic length of the chimney in the flow field is the projection length of the chimney in the flow direction of the flow field fluid, and the distance from the chimney to the living building is the shortest distance from the chimney to the living building.

[0012] Optionally, in step 2, when ln E is less than 6, that is, when the wind speed does not exceed 28 m / s, the turbulence intensity peak κ is linearly related to the logarithm of the kinetic energy E of the fluid medium, and the disturbance by the kinetic energy E of the fluid medium is small, and the diffusion of smoke around the living building is not obvious.

[0013] Optionally, in step 2, when ln E>6, that is, when the wind speed is not less than 28m / s, the turbulence intensity peak κ is greatly disturbed by the change of kinetic energy E of the fluid medium, and it intensifies with the increase of kinetic energy E, and the smoke diffuses significantly around the living building.

[0014] Optionally, under the premise that the spacing ratio γ cannot be arranged, the spacing ratio γ should be reduced

[0015] To sum up, the chimney and living building arrangement method proposed in the present invention can simply and effectively simulate the accumulation concentration of smoke discharged from the chimney. It can be seen that there are areas with low turbulence intensity and dispersed tail vortex distribution. The chimney and living building are arranged in this way, which can effectively reduce the accumulation of chimney exhaust gas near the living building and effectively improve the problem of the living building area being affected by the chimney exhaust gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the distribution diagram of flue gas components;

[0017] Figure 2 is the smoke turbulence intensity distribution diagram;

[0018] Figure 3 The curve of turbulence intensity changing with wind speed at different γ;

[0019] Figure 4 The streamline diagram of the flow field when γ = 0.4;

[0020] Figure 5 This is the flow field streamline diagram when γ=0.45. DETAILED DESCRIPTION

[0021] The following combination Figure 1-5 The present invention is described in further detail.

[0022] Existing smoke diffusion analysis generally uses the transport equation as the control equation for calculation. This method is generally more effective in accurately calculating application scenarios. For the optimization calculation of multiple working conditions, since the time history analysis of the flow field itself has a large workload and high calculation cost, it is very time-consuming to use this solution before the optimal layout solution is known.

[0023] In the present invention, reference is made to Figure 1 and Figure 2 By comparing the smoke component concentration and smoke turbulence intensity distribution of three-dimensional smoke diffusion, it can be seen that the smoke turbulence intensity distribution can effectively characterize the smoke component concentration. Therefore, the present invention discloses a method for arranging a living building and a chimney. First, the flow field of the chimney and the living building is simulated by CFD software, and then the reasonable distribution of the chimney and the living building is guided by the simulation results. Among them, the concentration of smoke diffusion is characterized by the turbulence intensity index of the fluid medium in the flow field. The arrangement method includes the following steps:

[0024] Step 1: Simulate the turbulence intensity distribution of the flow field around the chimney to obtain the turbulence intensity distribution of the flow field;

[0025] Step 2: Draw a curve of the maximum turbulent kinetic energy κ of the flow field and the kinetic energy E of the fluid medium under the conditions of different distances from the chimney to the living building and the spacing ratio γ of the characteristic length of the chimney in the flow field, and select E = 0.5ρν 2 The natural logarithm lnE is taken as one axis, and the peak value of turbulence intensity κ is taken as the other axis, and the curve of turbulence intensity changing with wind kinetic energy for different γ values ​​is obtained;

[0026] Step 3: In the curve obtained in step 2, select the characteristic value of the γ curve with smaller turbulent kinetic energy as the principle for optimizing the layout of living buildings and chimneys.

[0027] In a further embodiment, the characteristic length of the chimney in the flow field is the projected length of the chimney in the flow direction of the flow field fluid, and the distance from the chimney to the living building is the shortest distance from the chimney to the living building.

[0028] In a further embodiment, in step 2, when lnE is less than 6, that is, under the condition that the wind speed does not exceed 28 m / s, the turbulence intensity peak value κ is linearly related to the logarithm of the kinetic energy E of the fluid medium, and is less disturbed by the kinetic energy E of the fluid medium, and the diffusion of smoke around the living building is not obvious; when lnE is greater than 6, that is, under the condition that the wind speed is not less than 28 m / s, the turbulence intensity peak value κ is greatly disturbed by the change of the kinetic energy E of the fluid medium, and is aggravated with the increase of the kinetic energy E, and the diffusion of smoke around the living building is obvious. Under the premise that the spacing ratio γ cannot be arranged, the spacing ratio γ should be reduced.

[0029] Example

[0030] In this embodiment, the concentration of smoke diffusion is characterized by the turbulence intensity index of the fluid medium in the flow field. In the turbulence intensity distribution obtained in step one, the greater the turbulence intensity, the greater the negative pressure formed in the flow field, the easier it is to form accumulated smoke, and the greater the smoke concentration, the smaller the turbulence intensity, the lower the flow field streamline gradient, the easier it is for the smoke to diffuse, and the smaller the smoke concentration.

[0031] according to Figure 3 The data show that when γ is 0.45, Figure 5 As shown in Figure 2, the turbulence intensity is obviously low. When γ is 0.4, Figure 4 As shown, the turbulence intensity is still low. When γ is 0.5, the turbulence intensity is high. Therefore, γ takes a value between 0.4 and 0.45, that is, the optimal distance between the chimney and the living building is 0.4 to 0.45 times the characteristic length of the chimney in the flow field, and the optimal distance between the chimney and the living building is 0.45 times the characteristic length of the chimney in the flow field. That is, when γ is 0.4 to 0.45, it has a relatively good optimization effect, and when γ is 0.45, it has the best optimization effect.

[0032] The chimney and living building arrangement method proposed in the present invention can simply and effectively simulate the accumulated concentration of smoke exhausted from the chimney. From the calculation results, it can be seen that the turbulence intensity is low and the tail vortex distribution is dispersed, which can effectively reduce the accumulation of chimney exhaust gas near the living building and effectively improve the problem of the living building area being affected by the chimney exhaust gas.

[0033] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for arranging living buildings and chimneys, firstly simulating the flow field of chimneys and living buildings by CFD software, and then guiding the reasonable distribution of chimneys and living buildings by the simulation results, wherein: The concentration of smoke diffusion is characterized by the turbulence intensity index of the fluid medium in the flow field, and the arrangement method includes the following steps: Step 1: Simulate the turbulence intensity distribution of the flow field around the chimney to obtain the turbulence intensity distribution of the flow field; Step 2: Draw a curve of the maximum turbulent kinetic energy κ of the flow field and the kinetic energy E of the fluid medium under the conditions of different distances from the chimney to the living building and the spacing ratio γ of the characteristic length of the chimney in the flow field, and select E = 0.5ρν 2 The natural logarithm lnE is taken as one axis, and the peak value of turbulence intensity κ is taken as the other axis, and the curve of turbulence intensity changing with wind kinetic energy for different γ values ​​is obtained; Step 3: In the curve obtained in step 2, select the characteristic value of the γ curve with smaller turbulent kinetic energy as the principle for optimizing the layout of living buildings and chimneys.

2. The method for arranging living buildings and chimneys according to claim 1, characterized in that: In step three, when γ is between 0.4 and 0.45, a relatively good optimization effect is achieved, and when γ is 0.45, the best optimization effect is achieved.

3. The method for arranging living buildings and chimneys according to claim 1, characterized in that: The concentration of smoke diffusion is characterized by the turbulence intensity index of the fluid medium in the flow field. In the turbulence intensity distribution obtained in step one, the greater the turbulence intensity, the greater the negative pressure formed in the flow field, the easier it is to form accumulated smoke, and the greater the smoke concentration. The smaller the turbulence intensity, the lower the flow field streamline gradient, the easier it is for smoke to diffuse, and the smaller the smoke concentration.

4. The method for arranging living buildings and chimneys according to claim 1, characterized in that: In step 2, the characteristic length of the chimney in the flow field is the projected length of the chimney in the flow direction of the flow field fluid, and the distance from the chimney to the living building is the shortest distance from the chimney to the living building.

5. The method for arranging living buildings and chimneys according to claim 1, characterized in that: In step 2, when lnE < 6, that is, when the wind speed does not exceed 28 m / s, the turbulence intensity peak κ is linearly related to the logarithm of the kinetic energy E of the fluid medium, and the disturbance by the kinetic energy E of the fluid medium is small, and the diffusion of smoke around the living building is not obvious.

6. The method for arranging living buildings and chimneys according to claim 1, characterized in that: In step 2, when lnE>6, that is, when the wind speed is not less than 28m / s, the turbulence intensity peak κ is greatly disturbed by the change of the kinetic energy E of the fluid medium, and it intensifies with the increase of the kinetic energy E, and the smoke diffuses significantly around the living building.

7. The method for arranging living buildings and chimneys according to claim 2, characterized in that: Under the premise that the spacing ratio γ cannot be arranged, the spacing ratio γ should be reduced.

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