CN201352132Y - Tube cavity for ultrasonic gas meter - Google Patents

Abstract

The utility model relates to a tube cavity for an ultrasonic gas meter, which comprises a cavity, and a plurality of horizontally parallel partition plates are arranged in the cavity to divide the cavity into flow passages independent from one another. Since the utility model adopts the partition plates to divide the cavity into the layered flow passages independent from one another, that is, the prior single flow passage is divided into horizontally parallel n layers, the flow of the gas in the flow passages can receive relatively equal resistance, the flow speed is relatively uniform, and thereby the obtained flow speed U can more accurately reflect the flow speed of the gas.

Description

The pipeline cavity that is used for ultrasonic wave gas meter

(1) technical field

The utility model relates to a kind of pipeline cavity that is used for ultrasonic wave gas meter.

(2) background technology

Existing ultrasonic wave gas meter adopts time difference method to measure gas flow usually, and measuring principle as shown in Figure 1.When utilizing sound wave to propagate, it, measures its following current travel-time T because of the different characteristics of fluid flow direction difference velocity of propagation in fluid ₁With adverse current travel-time T ₂Difference, thereby speed and flow that Fluid Computation is flowed.

During measurement, ultrasound wave sounding receptacle is installed in the stream both sides, and with flow to into the θ angle.The ultrasound wave sounding receptacle of upstream sends ultrasound wave sounding receptacle and the Measuring Time (T that ultrasound wave is given the downstream ₁).Send ultrasound wave by reverse direction from the upstream ultrasound wave sounding of the ultrasound wave sounding receptacle receptacle in downstream then, and Measuring Time (T ₂).Can calculate gas flow rates (U) by these two times that obtain by ultrasonic sensor.

${\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="Y2008201711590007H1.png"\; state="\{\{state\}\}">T</figure-callout>}}_1\&ap;\frac{L}{C+U\cos \mathrm{\&theta;}}---\left(1\right)$

$T_2\&ap;\frac{L}{C-U\cos \mathrm{\&theta;}}---\left(2\right)$

$\stackrel{\&CenterDot;}{\&CenterDot;\&CenterDot;}U\&ap;\frac{L}{2\cos \mathrm{\&theta;}}(\frac{1}{T_1}-\frac{1}{T_2})---\left(3\right)$

In the formula: distance between the L-two ultrasound wave sounding receptacles, C-velocity of sound

The computing formula of gas flow is: Q=SL=SUT, Q-flow, S-unit cross-sectional area, L-flow path length, U-gas flow rates, T-gas flow time.

As shown in Figure 2, because the mobile resistance that be subjected to cavity inner wall of gas in stream is slow near the gas flow rate of chamber wall so flowing velocity is inhomogeneous, fast near the gas flow rate of central authorities.And be a mean speed by ultrasound wave conversion by the flow velocity U that formula (3) draws, unit cross-sectional area S and flow velocity U are multiplied each other can not reflect reality gas flow accurately simply.

(3) utility model content

Technical problem to be solved in the utility model is to provide a kind of pipeline cavity that is used for ultrasonic wave gas meter that improves the gas flow measurement accuracy greatly.

The described pipeline cavity that is used for ultrasonic wave gas meter comprises cavity, and the dividing plate that is provided with some horizontal parallel in the described cavity will be divided into separately independently stream in the cavity.

Further, described cavity cross-section is a rectangle.

Further, described dividing plate material is a stainless steel.

The utility model adopts dividing plate to be divided into independently each laminar flow road in the cavity, original single stream is changed into the n layer of horizontal parallel, make gas mobile in stream be subjected to identical relatively resistance, flowing velocity is even relatively, and then the flow velocity U that obtains can reflect gas flow speed more exactly.

(4) description of drawings

Fig. 1 is the measuring principle figure of ultrasonic wave gas meter in the prior art.

Fig. 2 is the structural representation of pipeline cavity in the prior art.

Fig. 3 is the described structural representation that is used for the pipeline cavity of ultrasonic wave gas meter of embodiment.

(5) embodiment

The utility model is described in further detail below in conjunction with embodiment, but protection domain of the present utility model is not limited to this.

With reference to Fig. 3, a kind of pipeline cavity that is used for ultrasonic wave gas meter comprises cavity 1, and the dividing plate 2 that is provided with some horizontal parallel in the described cavity 1 will be divided into separately independently stream 3 in the cavity.

Described cavity 1 cross section is a rectangle.

Described dividing plate 2 materials are stainless steel.

Claims (3)

1, a kind of pipeline cavity that is used for ultrasonic wave gas meter comprises cavity, it is characterized in that the dividing plate that is provided with some horizontal parallel in the described cavity will be divided into separately independently stream in the cavity.

2, the pipeline cavity that is used for ultrasonic wave gas meter according to claim 1 is characterized in that described cavity cross-section is a rectangle.

3, the pipeline cavity that is used for ultrasonic wave gas meter according to claim 1 is characterized in that described dividing plate material is a stainless steel.

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