RU1639405C - Target device - Google Patents

Abstract

The invention relates to accelerator technology. The purpose of the invention is to reduce gas leakage into the charged particle transport channel. An 8-tight Laval nozzle in which the central body is made in the form of a straight straight cylinder and the outer shell has a profiled inner surface have a sealed housing of the accelerator charged particles transport channel. In this case, a channel for passing gas through the nozzle is located between the outer shell and the central body, and in the wall of the central body there is a channel connected to an annular groove made on the outer surface of the central body at its outlet end. An analytical summary is given to calculate the length of the central body of 1 sf. 4 ip

Description

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The invention relates to a nuclear accelerator and can be used in experiments in nuclear physics,

An object of the invention is to reduce the leakage of gaseous target material into the particle transport channel.

In FIG. 1 shows a diagram of a gas target on a 1: 2 scale, general view; in FIG. 2 is an enlarged view of a plot of a gas target; in FIG. 3 is a change in the angle of rotation of the flow at the outlet edge of the nozzle from the flow velocity, where 5Lr is the limiting angle of rotation for various sections of the boundary layer; in FIG. 4 is a graph of the mass flow through the boundary layer at the exit edge of the sppe for M-5 on the geometric dimensions of the nozzle.

The target device shown in FIG. 1, contains a sealed housing 1, equipped with means for connecting to the channel for transporting a beam of charged particles from the accelerator and the system

 1 g02 + eat + 1

(1 -

k- 1

2.

where M is the Mach number at the output,

(T - Criminal section of the nozzle, m

(H - the fierce radix of cylindrical becoming: k, m;

k is the index of isoentropp gas;

y is the half-angle of the radial nozzle, rad.

The device operates as follows.

The target gas from the circulation loop enters the inlet nozzle 2, accelerates further into the target body 1, while continuing to expand beyond the outlet edge of the nozzle. To the meeting point of the inner edges of the flow, long conical Mach numbers at the outlet edge of the nozzle (M 5), a conical shock wave is formed. The amount of gas leakage into the accelerator channel is determined by the amount of medium flowing through the boundary layer formed on the outer surface of the cylindrical insert. The boundary layer is sucked through the groove 7 and channel b, thereby reducing the amount of leakage.

In FIG. Figure 4 shows the results of a numerical study of the leakage value for various nozzle geometry, where the following notation is used: r0 is the radius of the cylindrical insert; Ro - radius profiled but also the walls of the target body on

supply of the gaseous working medium of the target, and the under-expanded nozzle 2 Laval. The outer profiled shell 3 of the nozzle surface is connected to the housing, and a channel 5 for introducing a gas stream is formed between the central body 4 and the outer shell 3 of the nozzle 2. In order to reduce (or completely eliminate) gas leakage into the accelerator channel, the central nozzle body 4 is made in the form of a straight hollow cylinder with an inner annular channel 6 in the wall, which is a direct continuation of the annular groove 7 on the outer surface of the body at the exit edge, the length of the central body 1 is selected within

L i L, where L is the length of the profiled nozzle, m,

L is the length of the radial (non-profiled) nozzle, m

The value of L was determined from the following expression:

-G,

LM

Go

ctg y

nozzle exit edge; g is the amount of gas leakage into the accelerator channel (as a percentage of the mass flow rate of gas through the target), M is the Mach number in the flow core per

nozzle outlet edge

Point A in FIG. 4 corresponds to the leakage rate for the nozzle of FIG. 1. The geometric characteristics of the nozzle: g0 - 15mm, Ro-Zbmm. Inlet gas parameters

into the nozzle P 54 x 105 Pa; T - 385 K; / 6.84 kg / m3, where P, T, p - respectively pressure, temperature and gas density.

The nozzle is profiled so that the output number is 5. For deuterium consumption G 0.5

kg / s leakage into the accelerator channel accounts for 1.5% of the total mass flow.

Compared with the prototype, the proposed device has the following advantages aiecTBa; reduces gas leakage in

the accelerator channel is up to 1.5% of the total gas flow, and when the boundary layer is removed, the leak is completely eliminated, the width of the annular gap in the critical village of the annular nozzle is increased, which gives

the opportunity to simplify the technology of its resettlement.

(56) Ai mountain certificate of the USSR N-18C041. class G21 B 1/02, 1963. USSR Copyright Certificate

Kp N Og And 6/00. 1985.

Claims (2)

1. TARGET DEVICE, comprising a sealed enclosure equipped with means for connecting to the particle transport channel and the gaseous working medium supply system of the target, and an underexpanded Laval nozzle, in the central body of which there is a channel for passing charged particles, the inner surface of the outer shell is made profiled, and its outer surface is combined with the housing with the formation of an axially symmetric structure in which a channel for passing a gaseous working substance through the nozzle is located between the central body and the outer shell of the nozzle, characterized in that. in order to reduce gas leakage into the channel for transporting charged particles, a channel is made in the wall of the central body of the nozzle, the cross section of which has the shape of a ring, F i . f f J J T-st-ZG --- o - TE g . TUJL XrrtteZ & zg the stroke of which is connected to an annular groove made on the outer surface of the central body of the nozzle and its outlet end, while the length of the central body 1 is selected from the condition L s la L. L , Mk-l Jl -p ftgjr PM about where L is the length of the profiled nozzle, m; L is the length of the radial (non-profiled) nozzle, m. M is the Mach number at the nozzle exit: a, is the critical section of the nozzle, m2, th is the external radius of the central body, m; k is the exponent of the isentropic gas, y is the half-angle of the radial nozzle, rad. 2. The device according to claim 1, characterized in that the central body of the nozzle is made in the form of a straight hollow cylinder. Fugue. 7 / S //////////////// /////. FIG. 2 FZ.Z „4GF-4 12sn