CN102691671A - Designing method of impeller core main pump wheel - Google Patents

Abstract

The invention relates to a method for designing the impeller of a nuclear main pump. It gives the design formulas of the main geometric parameters of the impeller, the inlet diameter, the outer circle diameter of the impeller, and the outlet width of the impeller blades. The thickness of the front cover plate side of the impeller blade is 30% smaller than that of the rear cover plate side, and the thickness of the blade increases linearly and uniformly from the front cover plate side to the rear cover plate side; the thickness of the blade increases gradually from the inlet side along the streamline direction to the outlet Large, where the thickness of the inlet side is 45% of the thickness of the outlet side. The streamline wrap angle near the front cover of the blade is 10° larger than the streamline wrap angle near the rear cover. The number of blades of the impeller is 6-8.

Description

A Design Method for Nuclear Main Pump Impeller

technical field

The invention relates to a method for designing main parts of a nuclear main pump, in particular to a method for designing an impeller of a nuclear main pump.

Background technique

In the reactor coolant system, the nuclear main pump is the only rotating equipment, and it is also the pressure boundary equipment of the primary circuit. In the primary circuit of a nuclear power plant, the nuclear main pump is used to drive the coolant to circulate in the RCP (Reactor Cooling System) system, and continuously transfer the heat generated in the core to the secondary side (secondary circuit) circulating water of the steam generator , to ensure that the reactor works stably.

The circulating water in the primary cycle absorbs and transmits a large amount of heat through contact with the nuclear reactor. The temperature and pressure of the circulating water are high, and it is also radioactive. Therefore, the nuclear main pump driving the circulating water has high temperature and high pressure requirements, and the nuclear main The pump is the only high-speed operating equipment in the nuclear island, and its requirements for safety and performance are much higher than those of ordinary water pumps.

The nuclear main pump is mainly composed of pump casing, impeller, guide vane, motor and other components, and the impeller is the core hydraulic component of the nuclear main pump, and is also the only moving element. The geometric parameters of the impeller have a great influence on the performance of the nuclear main pump, so The impeller has a significant impact on the safety and hydraulic performance of the nuclear main pump.

Contents of the invention

In order to solve the above problems, the present invention provides a method for designing the impeller of a nuclear main pump. By improving the design method of several important design parameters of the impeller, the flow condition is improved, and the hydraulic performance and reliability of the nuclear main pump are improved.

The technical scheme adopted to realize the above-mentioned purpose is:

The main structural parameters of the nuclear main pump impeller are obtained by the following calculation method:

(1) impeller inlet diameter D _j

${\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 200</span>}}{\mathrm{<span\; class="notranslate">\; 100</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt[\mathrm{<span\; class="notranslate">\; 3</span>}]{\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">Q</figure-callout></span><figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">\; </figure-callout>}}{\mathrm{<span\; class="notranslate">\; </span>}}}$

In the formula: D _j - impeller inlet diameter, m;

Q-flow rate in design working conditions, cubic meters per second;

n-impeller speed, rev/min;

n _s - specific speed.

(2) Impeller outlet diameter D ₂

The diameter of the impeller outlet is taken as the arithmetic average of the diameters of the front and rear cover plates of the impeller.

${\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 20</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="h"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">h</figure-callout></span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1.083</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 650</span>}}{\mathrm{<span\; class="notranslate">\; 3571</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 110</span>}}{{\mathrm{<span\; class="notranslate">\; 10</span>}}^{\mathrm{<span\; class="notranslate">\; 5</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt[\mathrm{<span\; class="notranslate">\; 3</span>}]{\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">Q</figure-callout></span><figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">\; </figure-callout>}}{\mathrm{<span\; class="notranslate">\; </span>}}}$

In the formula: D ₂ - impeller outlet diameter, m;

D ₂₀ - the maximum outlet diameter of the impeller, m;

D _2h - the minimum outlet diameter of the impeller, m;

Q-flow rate in design working conditions, cubic meters per second;

n-impeller speed, rev/min;

n _s - specific speed.

(3) Exit width b ₂

${\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="b"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">b</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1.05</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 200</span>}}{\mathrm{<span\; class="notranslate">\; 1263</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 135</span>}}{\mathrm{<span\; class="notranslate">\; 10000</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt[\mathrm{<span\; class="notranslate">\; 3</span>}]{\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">Q</figure-callout></span><figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">\; </figure-callout>}}{\mathrm{<span\; class="notranslate">\; </span>}}}$

In the formula: b ₂ - the width of the outlet of the impeller blade, m;

Q-flow rate in design working conditions, cubic meters per second;

n-impeller speed, rev/min;

n _s - specific speed.

A nuclear main pump impeller, the structure of which includes: an impeller cover plate, blades, a wheel hub and the like. The inlet diameter, outlet diameter and blade outlet width of the impeller are determined by the above-mentioned design method. The thickness of the front cover plate side of the impeller blade is 30% smaller than that of the rear cover plate side, and the thickness of the blade increases linearly and uniformly from the front cover plate side to the rear cover plate side; the thickness of the blade increases gradually from the inlet side along the streamline direction to the outlet Large, where the thickness of the inlet side is 45% of the thickness of the outlet side. The streamline wrap angle near the front cover of the blade is 10° larger than the streamline wrap angle near the rear cover. The number of blades of the impeller is 6-8.

The beneficial effects of the invention are: the impeller designed by the design method has excellent hydraulic performance, good anti-cavitation performance, and improves the reliability of the nuclear main pump.

Description of drawings

Fig. 1 is the projection diagram of impeller axis plane of an embodiment of the present invention

Fig. 2 is the impeller blade figure of the same embodiment

In the figure: 1. Impeller cover plate, 2. Impeller inlet diameter, 3. Impeller outer circle diameter, 4. Impeller maximum outer circle diameter, 5. Impeller minimum outer circle diameter, 6. Impeller blade outlet width, 7. Blade, 8 .Wheels.

Detailed ways

Figures 1 and 2 together define the impeller shape of this embodiment. It has an impeller cover plate (1), which has a front cover plate and a rear cover plate respectively. It is a closed impeller, and the number of blades is 6≤z≤8, which can improve the flow condition and improve the hydraulic performance and reliability of the nuclear main pump. . The present invention determines the impeller inlet diameter (2) D _j , the impeller outlet diameter (3) D ₂ , and the impeller blade outlet width (6) b ₂ through the following relational expressions.

${\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 200</span>}}{\mathrm{<span\; class="notranslate">\; 100</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt[\mathrm{<span\; class="notranslate">\; 3</span>}]{\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">Q</figure-callout></span><figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">\; </figure-callout>}}{\mathrm{<span\; class="notranslate">\; </span>}}}<span\; class="notranslate">\; ;</span>$

${\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 20</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="h"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">h</figure-callout></span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1.083</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 650</span>}}{\mathrm{<span\; class="notranslate">\; 3571</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 110</span>}}{{\mathrm{<span\; class="notranslate">\; 10</span>}}^{\mathrm{<span\; class="notranslate">\; 5</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\sqrt[\mathrm{<span\; class="notranslate">\; 3</span>}]{\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">Q</figure-callout></span><figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">\; </figure-callout>}}{\mathrm{<span\; class="notranslate">\; </span>}}}<span\; class="notranslate">\; ;</span>$

${\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="b"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">b</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1.05</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 200</span>}}{\mathrm{<span\; class="notranslate">\; 1263</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; \&CenterDot;</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 135</span>}}{\mathrm{<span\; class="notranslate">\; 10000</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt[\mathrm{<span\; class="notranslate">\; 3</span>}]{\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">Q</figure-callout></span><figure-callout\; id="3"\; label="Q\; no"\; filenames="DEST\_PATH\_HSB00000842254800011.png"\; state="\{\{state\}\}">\; </figure-callout>}}{\mathrm{<span\; class="notranslate">\; </span>}}}<span\; class="notranslate">\; .</span>$

The thickness of the front cover plate side of the impeller blade is 30% smaller than that of the rear cover plate side, and the thickness of the blade increases linearly and uniformly from the front cover plate side to the rear cover plate side; the thickness of the blade increases gradually from the inlet side along the streamline direction to the outlet Large, where the thickness of the inlet side is 45% of the thickness of the outlet side. The streamline wrap angle near the front cover of the blade is 10° larger than the streamline wrap angle near the rear cover. The number of blades of the impeller is 6-8.

Claims (2)

1. examine the main pump impeller design method for one kind, comprise the design formula of the exit width of impeller main geometric parameters inlet diameter, impeller outer circular diameter, impeller blade.It is characterized in that: relation below being fit between impeller geometric parameter and the pump design conditions point performance parameter:

$D_j=(4+\frac{n_s-200}{100})\&CenterDot;\sqrt[3]{\frac{Q}{n}};$

$D_2=\frac{D_{20}+D_{2h}}{2}=(1.083+\frac{n_s-650}{3571})\&CenterDot;(1+\frac{n_s-110}{{10}^5})\&CenterDot;\sqrt[3]{\frac{Q}{n}};$

$b_2=(1.05-\frac{n_s-200}{1263})\&CenterDot;(1-2\&CenterDot;\frac{n_s-135}{10000})\&CenterDot;\sqrt[3]{\frac{Q}{n}}.$

In the formula: the lift of Q-design conditions, rice;

D ₂-impeller outlet diameter, rice;

b ₂-impeller blade exit width, rice

D ₂₀The maximum outlet diameter of-impeller, degree;

D _2hThe minimum outlet diameter of-impeller, degree;

The n-wheel speed, rev/min;

n _s-specific speed, rev/min.

2. a kind of nuclear main pump impeller design method according to claim 1 is characterized in that: nuclear main pump impeller structure comprises: impeller cover (2), blade (7), wheel hub (8).The inlet diameter of impeller, outlet diameter, blade exit width adopt above-mentioned design method to confirm.The blade front shroud side thickness of impeller is littler by 30% than back shroud side thickness, and vane thickness from front shroud side direction back shroud side according to linear uniform thickened; Blade increases from inlet side along grain direction to the thickness of outlet gradually, and wherein inlet side thickness is 45% of outlet limit thickness.Blade is big 10 ° near back shroud place streamline cornerite near front shroud place streamline cornerite ratio.The number of blade of impeller is 6～8.

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