SU754228A1 - Radiometer - Google Patents

Description

one

The device relates to radiometry and can be used in metrology and to control energy processes.

There are known devices for measuring 5 fluxes of radiation, containing a receiving surface, a heater, a thermopile (TB) and a radiator [].

The disadvantage of these devices is the need to electrically isolate the working ends of the thermopile from the metal body of the radiometer, which creates thermal isolation of the TB from the radiometer, which lowers it. sensitivity and increases time. Ιί measurement.

The closest to the proposed is a radiometer containing a ball cavity with a heater located inside the cavity, and a radiator, 2C each thermocouple (TP) is placed on the body of the radiometer with a step decreasing from the inlet according to a certain law].

The disadvantages of this radiometer are, firstly, the need to electrically isolate the working ends of the TP from the metal body of the radiator, and this creates thermal insulation of the TP from the radiometer, which reduces 30

2

sensitivity and increases the measurement time, and because of the impossibility of achieving its homogeneity, introduces an error in the integrating properties of TB, first, the manufacture of ring TB with varying pitch is a laborious manual process.

The purpose of the invention is to improve the measurement accuracy, reduce measurement time and simplify the technology of cooking,

This goal is achieved by the fact that the ball cavity is electrically connected by branches with a radiator, the material of the ball cavity and the radiometer is a thermocouple with the material of the branches, the ball cavity and the radiator are copper, and the branches are constantan, and the length of each branch corresponds to the resistance determined by the formula

Γ0Π5ί

I p = ---- ’

5 (n ^ 2'et1)

where E is the number of the number, £ - 1,2,., .. n),

the origin is the point opposite to the inlet of the radiometer.

Fig, 1 shows the proposed

radiometer; in fig. 2 - electric

754228

a radiometer diagram explaining its principle of operation.

The radiometer contains a spherical cavity 1 made of copper, inside which is a heater 2 of high resistance wire in a grid located near the cavity wall, constantan branches TB 3 electrically connected to the spherical cavity 1 and radiator 4 and located in a plane passing through the axis of the inlet , radiator 4, made of copper, 'electrically connected to branches TB 3 and inlet 5 of the radiometer.

Radiomart works as follows.

A current is passed through heater 2, the power of which exceeds the measured one, for example, P, and the current or its proportional voltage (thermopower) arising in TB is fixed,

The receipt is entered into the inlet 5 of the radiometer and the change (appearance) of current or thermoEMF is monitored. Then the heating is reduced until the former value of the current or • thermopower is restored • and the new value of the heating power is fixed.

The measured flow is defined as P _o - P, The measurement operation can be performed automatically.

Common wire 6 (see. Figure 2) pred'stavlyaet spherical surface, and the total wire radiator 7, they are connected in parallel included constantan branches, each branch is represented by series-connected source TEDS and internal resistance K _to "point Parallel branches pass through the output lead a radiometer (which removes the resulting signal), also represented by a series-connected TEDS source Eo and internal resistance.

On the presented circuit, you can find the total current in the output wire

N Ek

ten

15

20

25

thirty

35

40

45

D = ·

50

K-1 K _to

£ _к - Е _с - thermoEMF of the branches minus the EMF of the wire the drive is made of the same material as the radiometer and this EMF is small, in the general case this leads to the current having the form 3 = + ie, it contains

a component that is not related to the temperature distribution over the radiometer, but depends only on its value at the __ point of the wire. If you select ¹ this place at the inlet, το _χ ^ as the calculations show, it is practically Ε χ = _k

55

60

Scientifically does not change when measuring the flow and when it is replaced. For these reasons, _Proof mbzhno not taken into account. In addition, the denominator is D-constant.

N with

Thus, —ί £,

Hence we determine the D _n .

When integrating the power lost by the radiometer, the integral is replaced

sum - ^> Σ.ί _{1 /} Δ ^ 5>

and k = 1 ^to

The relative temperature appears to be proportional to the thermopower ε _{κ the} area at which it is proposed *

= const, equals

where r is the radius of the radiometer, φ _{χ is the} angular coordinate of the th branch of the TP.

Otherwise, Δ to 3 can be represented as D _to 5 = Spu (2 K *)

From the obtained amounts of this expression it is clear that the total current will be me-. power loss if fulfilled

p _ d · _ SOP e 1 ^to k - - 2Ϊ --—

541 - ^ (2.0 (-1)

Claims (2)

Claim 1, A radiometer containing a ball cavity with a heater located inside the cavity, and a radiator, characterized in that, in order to improve measurement accuracy, reduce measurement time and simplify manufacturing technology, the ball cavity is electrically connected · with branches to a radiator, and the material is ball cavity and the radiator is a thermocouple with the material of the branch, and the length of each branch corresponds to the resistance determined by the formula _{S0P2 {} . where E is the branch number (£ = 1,2, ,,, η), the origin is the point opposite to the inlet of the radiometer, 2, Radiometer pop. 1, characterized in that the ball cavity and the radiator are made of copper, and the branches are of constantan.