NATURAL LIGHTING OF INDUSTRIAL PREMISES IN THE LOCOMOTIVE DEPO

ABSTRACT

A methodik for substantiating the parameters of natural lighting in a production facility in a locomotive depot is proposed. Received numerical values of the area of light openings in the extension of the production facility, the projected workshop of a large of type of current repair for 3VL80^S electric locomotives in the locomotive depot, which ensure full compliance with of sanitary and hygienic standards for natural lighting on the same level with standard norms.

AННОТАЦИЯ

Предложена методика обоснования параметров естественного освещения производственного помещения в локомотивном депо. Получены численные значения площади световых проёмов в пристройке производственного помещения, проектируемого цеха крупного вида текущего ремонта для электровозов 3ВЛ80^С в локомотивном депо, которые обеспечивают полное соответствие санитарно - гигиенических норм по естественному освещению стандартным нормативам.

Keywords: light opening, area, luminous flux, natural lighting, side lighting, calculation, coefficient, standard.

Ключевые слова: световой проём, площадь, световой поток, естественное освещение, боковое освещение, расчёт, коэффициент, норматив.

In railway transport and in transport construction, in order to create healthy and highly productive working conditions during the repair, maintenance and operation of rolling stock, as well as in ensuring the safety of train traffic, natural lighting is of particular importance, which is used for general lighting of production and utility rooms. The specified lighting is created by the radiant energy of the sun and has the most favorable effect on the human body.

With this type of lighting, one should take into account meteorological conditions and their changes during the day and periods of the year for a given, specific, area. The foregoing is necessary in order to know how much natural light will enter the room through the arranged light openings of the building: windows - with side lighting; skylights of the upper floors of the building - with overhead lighting. With combined natural lighting, side lighting is added to the top lighting.

The main task of lighting calculations for industrial (residential) buildings and structures for  naturals lighting, created by direct sunlight and diffused light from the sky, is to determine the required area of their light openings.

To characterize light, certain lighting concepts and quantities are used [1], the main of which are luminous flux, luminous intensity, illumination and brightness.

The purpose of this study is to substantiate the parameters of natural lighting of the extension of the production premises of the projected workshop for the maintenance of TR - 3 electric locomotives 3VL80^S in the locomotive depot.

The algorithm for realizing the goal of the research is as follows.

The calculation of the area of light openings with side lighting of the mentioned extension is carried out according to the formula [2]:

                                                                            (1)

where S₀ - area of light openings, m²;

ℓ_N - is the normalized value of the natural light factor, %.

The coefficient of natural illumination (CNI) is the ratio of illumination at a given point inside the room to the simultaneous value of the external horizontal illumination created by the light of a completely open sky, expressed as a percentage.

The value of the normalized value of the specified CNI for industrial buildings located in different areas according to the resources of the light climate is determined by the following formula:

                                                                                                    (2)

where ℓ_H - is the normal value of the natural light factor, %;

m_N - coefficient taking into account the peculiarities of the light climate of the administrative region;

N - groups number group of the administrative region according to natural light supply;

S_п - room floor area, m²;

К₃ - factor determined taking into account the dust content of the room, the location of the glasses (tilted, horizontal or vertical) and the frequency of cleaning;

η₀ - light characteristic of windows;

К_build - coefficient taking into account window shading by buildings opposing;

τ₀ - total coefficient light transmittanc;

r₁ - coefficient taking into account the increase in the coefficient of natural illumination with side lighting due to the light reflected from the surface of the room and the underlying layer adjacent to the building.

The value of the total coefficient light transmittance is determined by the following relationship, that is 

τ₀ = τ₁ · τ₂ · τ₃ · τ₄ · τ₅                                                                                          (3)

where τ₁ – coefficient light transmittance of the material;

τ₂ – coefficient taking into account the loss of light in the bindings of the light opening;

τ₃ – coefficient taking into account light losses in load-bearing structures;

τ₄ – coefficient that takes into account the loss of light in sun protection devices;

τ₅ – coefficient, which is not taken into account in calculations for side lighting.

The coefficient r₁ given above depends on the weighted average reflection coefficient of the surfaces of the room Р_av (%), which is determined by the formula for side and top lighting:

                                                                  (4)

where Р_ceil, Р_wall, Р_fl – respectively, the reflection coefficient of the ceiling, walls and floor;

S_ceil, S_wall, S_fl – respectively, ceiling, wall and floor areas, m². 

S_ceil = L · B; S_wall = 2 · H · (L+B); S_fl = L · B, m²                                           (5)

where В - room width, m;

L - room length, m;

Н - room height, m.

Further, we provide a rationale for the natural lighting parameters of the extension of the production premises of the projected workshop for the maintenance TR - 3 of electric locomotives 3VL80^S for the following initial data: the locomotive depot is located in the fifth group of administrative districts in terms of natural light supply, and the geometric parameters of the said extension are L = 132 m in length, width H = 12 m and height H = 10,8 m. Adopted lateral one-sided natural lighting.

1. We determine the value of the weighted average reflection coefficient of the room according to formula (4) taking into account formula (5), that is

It's accepted here: Р_ceil = 50%, Р_wall = 10% и Р_fl = 70%.

According to [3], when the ratio of the length of the room to its depth is one, taking into account the ratio of the depth of the room to its height from the level of the conditional work surface to the top of the window from 1,5 to 2,5 units and the ratio of the distance of the calculated point from the outer wall to the depth of the room in 0,7 units, value r₁ ≈ 2.0.

2. Determine the value of the total coefficient of light emission 

τ₀ = 0,8 · 0,75 · 1,0 · 1,0 = 0,6

where τ₁ = 0,8 – window glass sheet double;

τ₂ – bindings for windows and lanterns of industrial buildings, wooden, τ₂ = 0,75;

τ₃ – loss light at side lighting, τ₃ = 1,0;

τ₄ – retractable adjustable blinds and curtains (inter-pane, internal, external, τ₄ = 1,0;

τ₅ – side lighting is not taken into account, τ₅ = 0.

With high accuracy and the third category of visual work, the sub - category of which is "b", and the contrast of the object with the background and its characteristic is for average - the magnitude of the normal value of the CNI is ℓ_Н = 1,2%.

Therefore, for these light apertures, which are oriented along the horizon to the northeast, the value of the light climate coefficient of the administrative region is m_N = 0,8 [4].

Then, we have

ℓ_N = 1,2 · 0,8 = 0,96 %.

For industrial premises with an air environment containing less than 1 mg / m3 of dust, smoke and soot in the working area, and an angle of inclination of the light-transmitting material to the horizon of 46 - 75 degrees with two cleanings of the glazing of light openings per year, the safety factor is equal to K₃ = 1, 5. The value of the light characteristics at a side light at according to [5] is η₀ = 9,25. We accept the value of the coefficient K_build = 1,4.

Hence

Thus, to in order for the sanitary and hygienic standards of natural lighting to comply with the standards, the required area of light openings in the extension of the production premises of the designed workshop for the maintenance TR - 3 of electric locomotives 3VL80^S locomotive depot should be more than two hundred and forty - six square meters.

Reference:

1. Ablyalimov O. S. On the study of artificial lighting at railway transport enterprises [Text] / O. S. Ablyalimov, I. R. Kayumov // VIII-th interuniversity scientific and practical conference "Young scientific researcher" / Tashkent Institute . eng. railway transport. - Tashkent, 2010. - pp. 85 - 87.
2. Belyakov G. I. Occupational health and safety: a textbook for secondary vocational education / G. I. Belyakov. - 3rd ed., revised and additional - Moscow: Yurayt Publishing House, 2019. - 404 p.
3. Occupational safety in railway transport and transport construction / Edited by of A. V. Loshinins. General course. - M.: Transport, 1971.
4. Normatov Sh. N. Calculation of artificial lighting in industrial premises [Text] / Sh. N. Normatov, M. B. Tulyagankhodzhaeva // Methodological guidelines for graduation design. Part II / Tashkent in-t. eng. railway transport. - Tashkent, 1987. - 31 p.
5. Ablyalimov O. S. Calculation of illumination in the industrial premises of the locomotive depot [Text] / O. S. Ablyalimov, M. M. Topilov // VIII-th interuniversity scientific and practical conference "Young scientific researcher" / Tashkent in-t. eng. railway transport. - Tashkent, 2010. - pp. 71 - 73.