What is smartfactory

Smart factories have emerged as the future of manufacturing, revolutionizing industrial processes through advanced technologies and automation. These factories, characterized by interconnected machines and intelligent systems, are reshaping the manufacturing landscape by enhancing productivity, efficiency, and quality control. The significance of smart factories lies in their ability to improve productivity by enabling real-time monitoring, control, and optimization of operations. With the integration of AI tools, data analytics, and IoT, these factories can analyze real-time data, identify quality issues, and rectify them proactively, resulting in reduced defects and consistent product quality. Resource management becomes more effective through data analytics, allowing for predictive analysis of raw material requirements, inventory management, and labor needs. This optimization helps minimize waste, implement just-in-time practices, and increase efficiency. Safety and worker experience are enhanced in smart factories by utilizing automated machines for dangerous and repetitive tasks, reducing human interaction with hazardous environments. Augmented reality and wearable technology provide real-time instructions to workers, improving their efficiency and minimizing errors. Data-driven decision-making is a key aspect of smart factories, as they collect, monitor, and analyze data from machines, equipment, and workers. This analysis enables insights into production sequences, identifies repetitive mistakes, and patterns in machine downtime, and optimizes maintenance schedules, leading to improved manufacturing processes, reduced downtime, and enhanced productivity. The technologies used in smart factories, such as cloud computing, big data analytics, augmented reality, and industrial IoT, play a crucial role in enabling their capabilities. Cloud computing facilitates centralized data storage and monitoring, while big data analytics enables informed decision-making by identifying trends and patterns. Augmented reality enhances worker performance, and industrial IoT facilitates seamless integration and data collection across manufacturing systems. The evolution of smart factories occurs through four levels: connected data, predictive analysis, prescriptive analysis, and AI-driven automation. Advancements in AI and machine learning enable proactive analysis, predictive insights, and solutions automation, reducing human intervention and optimizing production processes. The global significance of smart factories is recognized by manufacturers and governments worldwide. These factories contribute to sustainability and environmental friendliness by reducing waste, increasing productivity, and minimizing resource consumption, ultimately reducing carbon emissions. Governments worldwide are actively promoting smart manufacturing initiatives and investing in the development of smart factories. Initiatives like the New Smart Manufacturing RFP in the USA, Manufacturing Made Smarter Challenge in the UK, Korea Smart Factory Initiative in South Korea, Udyog Bharat 4.0 in India, UAE Unveils Industry 4.0 in the UAE, Industrie Duv Future in France, and High Tech Strategy 2025 in Germany demonstrate the global commitment to fostering smart manufacturing.

Plc panel components and design

what is plc

what  is PLC  

Plc or plc controller is basically an board used to programming the machine in a preordely way, likewise i showing in above figures this one is designed for an rac plant,

In this article I will discuss with you the , wiring connection and components of plc, in terms of RAC PLANT

What is smps & what is the use of smps

Let's learn about this with an example u need to charge your smartphone so u need to use an charger to charge your phone for continuous supply of voltage

Same in the sense SMPS have same purpose it distribute constant voltage 12/24 voltage around the panel in case your are using module box

MCB- MCB are available in the difference variant in the market , if it's. 100 amp. Plus then it's called as MCCB

THIS IS SERVED IN THE CIRCUIT IF THERES HIGH VOLTAGE OR AMPRE DIFFERENCE JN THE CIRCUIT, IN THAT CASE MCB going to trip   it can be single pole or 3 poles 

in 4 connection MCB the fourth one is for neutral wire connection.

CONTACTORS - Contractors are basically coins those serves inthe circuit to of & offf the motors , when you  turned on/ off the switch, 

These are directly connected to the T1.T2.T3 point of the MCB, with each face RYB, RESPECTIVELY

THE A1 &A2 points are for coils to turn on / off, 

The start stop switch is added between these two

.

The MCB is really expensive & the compressor & motors repair cost is also high  if overload doesn't worked properly the contactor simply burn to safeguard the compressor /motor

Overload , overload is also served for the safety fo contactor as it doesn't have any safety of its own,

shape factor or view factor

SHAPE FACTOR OR VIEW FACTOR OR CONFIGURATION FACTOR:

Radiation heat transfer between surfaces depends upon the orientation of the surfaces relative to each other as well as their radiation properties and temperatures.

To account for the effects of orientation on radiation heat transfer between the surfaces,

a new parameter VIEW FACTOR is defined which is purely geometric quantity and is independent of radiation properties and temperatures.

Assumptions:

• The surfaces are diffuse emitter.
• The radiation that strikes a surface need not to be absorbed by that surface.
• Radiation that strikes a surface after being reflected by other is not considered in the evaluation of view factor.

The radiation shape factor is represented by the symbol F_ij ,

which means the shape factor form a surface, A_i to another surface A_j.

Thus the radiation shape factor F₁₂ of surface A₁ to surface A₂ is

 

SHAPE FACTOR RELATIONS:

(i) RECIPROCITY RELATION:

A1F12 = A2F21

 Reciprocity Relation is valid between any two surfaces even when there are more than two number of surfaces involved in Radiation Heat Exchange.

(ii) SUMMATION RULE:

If there are n number of surfaces involved in any radiation heat exchange then.

F₁₁ + F₁₂ + F₁₃ + …………….F_1n = 1

F₂₁ + F₂₂ + F₂₃ + ……………. F_2n = 1

.

F_n1 + F_n2 + F_n3 + ………..F_nn + 1

TOTAL SURFACES FOR VIEW FACTORS FOR N SURFACES OF AN ENCLOSURE

• Numbers of relation given by summation rule =N
• Numbers of relations given by reciprocity rule,

     

• The total numbers of view factors that need to be evaluated directly,

      

SUPERPOSITION RULE:

 F_1-(2,3) = F_1-2 + F_1-3

 SYMMETRY RULE:

Two or more surfaces that posses symmetry about a third surface will have identical view factors from that surface.

If the surface 2 and 3 are symmetric about surface 1 then F_1-2=F_1-3

GENERAL CASES:

CROSS STRING METHOD:

The each length is assumed to Be a strings connected between two points.

Cross Strings → The strings which crosses each other.

Uncrossed strings → The strings which do not cross each other.

L_i = length of string on surface i.

AB → 1 surface

CD → 2 surface

Special Case:

(Length)₁ = (Length)₂ Both surface are infinite in plane perpendicular to plane of paper.

 

radiation network analysis

RADIATION NETWORKS:

IRRADIATION (G)  

Irradiation (G) is defined as the total thermal radiation incident upon a surface per unit time per unit area (in W/m²)

RADIOSITY (J):

The total thermal radiation leaving a surface per unit time & per unit area is called radiosity of the surface.

J = Emitted Energy + Reflected Part of Incident energy,

The net radiation heat exchange between the surface & all of its surroundings is given by,

The equivalent radiation circuit is,

Radiation heat exchange between two finite surfaces:

,The equivalent radiation circuit is

This space resistance shall exist in the space between two surfaces exchanging heat by radiation.

Complete radiation network between two surfaces exchanging heat by radiation:

Therefore,

APPLICATIONS OF RADIATIONS NETWORKS:

(i) Radiation Exchange Between two Infinitely Large Plane Surfaces:

(ii) TWO INFINITELY LONG CYLINDERS:

 

Therefore,

RADIATION SHIELDS:

F₁₂ = 1, F₂₁ = 1

 

Since surfaces are very large

A₁ = A₂ = A₃ = 1 and F₁₃ = 1, F₃₂ = 1

Therefore,

radiation heat transfer

RADIATION HEAT TRANSFER:

(i) Thermal energy emitted by matter as a result of vibrational and rotational movements of molecules, atoms and electrons.

(ii) The energy is transported by electromagnetic waves (or photons).

(iii) Radiation requires no medium for its propagation, therefore, can take place also in vacuum.

BASIC DEFINITIONS:

TOTAL HEMISPHERICAL EMISSIVE POWER (E)

(i) It is defined as the radiation energy emitted from the surface of a body per unit time & per unit area in all possible hemispherical directions integrated over all the wavelengths (in J/s m² or W/m²).

BLACK BODY

(i) Different bodies emits different amount of radiation even if they are at same temperature.

(ii) A body which emits maximum amount of radiation at a given temperature is known as BLACK BODY.

(iii) A black body is defined as perfect emitter and absorber of radiation.

 TOTAL EMISSIVITY (Є)

Total emissivity of a body is defined as the ratio between total hemispherical emissive power of a non-black body & total hemispherical emissive power of a black body both being at the same temperature.

MONOCHROMATIC (OR) SPECTRAL EMISSIVE POWER (E_λ):

E_λ at a particular wavelength λ is defined as a quantity which when multiplied by dλ shall give the radiation energy emitted from the surface of a body per unit time per unit area in the wavelength region λ to λ + dλ.

 ABSORPTIVITY (α), REFLECTIVITY (ρ) & TRANSMISSIVITY (τ)

• Absorptivity(α) is the fraction of incident radiation absorbed.
• Reflectivity(ρ) is the fraction of incident radiation reflected.
• Transmissivity (τ) is the fraction of incident radiation transmitted.

 

ABSORPTIVITY (α) = 50/100 = 0.5 = Fraction of radiation energy incident upon a surface which is absorbed by it.

REFLECTIVITY (ρ) = 25/100 = 0.25 = Fraction of radiation energy incident upon a surface which is reflected by it.

TRNASMISSIVITY (τ) = 25/100 = 0.25 = Fraction of radiation energy incident upon a surface which is transmitted by it.

• FOR ANY BODY

       α + ρ + τ = 1

• For opaque body, which do not transmit any energy,

       τ = 0,  α + ρ = 1

• For black body, α = 1 [as it absorbs all energy incident]
• For white body, which reflects all energy incident ,τ  = 1

LAWS OF THERMAL RADIATION:

KIRCHOFF’S LAW OF RADIATION:

The law states that whenever a body is in thermal equilibrium with its surrounding’s its emissivity is equal to its absorptivity.

α = ϵ

 STEFAN BOLTZMANN’S Law:

The law states that the total hemispherical emissive power of a black body is directly proportional to fourth power of the absolute temperature of black body.

 

 Stefan BoltzmannConstant= 5.67 × 10^-8 W/m² k⁴

 PLANCK’S LAW OF THERMAL RADIATION:

The planck law describes the theoretical spectral distribution for the emissive power of a black body which is the amount of radiation energy emitted by a blackbody at a thermodynamic temperature T per unit time per unit surface area and per unit wavelength.

 WEIN’S DISPLACEMENT LAW:

The wavelength at which E_bλ will be maximum at a specified temperature can be found out by differentiating E_bλ  w.r.t  λ and then putting equal to zero.

We get,  λ_mT = 2897.8  μmK

LAMBERT’S COSINE LAW

The intensity of radiation in a direction θ from the normal to a diffuse emitter is proportional to cosine of the angle θ.

I= I_n cos θ, I_n = normal intensity of radiation

RADIATION INTENSITY:

The ideal intensity I_b is defined as the energy emitted from an ideal body(black body which is diffuse emitter) ,per unit projected area, per unit time ,per unit solid angle.

heat exchangers

HEAT EXCHANGERS:

Introduction

Heat exchanger is a steady flow adiabatic device (open system) in which two flowing fluids exchange or transfer heat between them without using or gaining any heat from the ambient.

Examples:

(1) Economizer [Flue gases – Feed water]

(2) Air Preheater [Hot gases – Combustion air]

(3) Superheater [Flue gases – dry saturated Steam]

(4) Cooling Tower [Hot water –Atmosphere air]

(5) Jet Condenser [Steam – cold water]

(6) Oil cooler

(7) Steam Condenser (Vapour – Liquid): Steam condenser is a shell & tube Heat Exchanger.

From thermodynamics, we know that heat transferred in a constant pressure process is equal to change in enthalpy of fluid and as we commonly assume in any heat exchanger that both hot & cold fluids are flowing through the heat exchanger at constant pressure.

Rate of decrease of enthalpy of hot fluid = Rate of increase of enthalpy of cold fluid

 

CLASSIFICATION OF HEAT EXCHANGERS ON BASIS OF CONTACT:

(i) INDIRECT CONTACT TRANSFER TYPE HEAT EXCHANGERS,

In this type of heat exchangers, both hot & cold fluids do not come into direct contact with each other but the transfer of heat occurs between them through a pipe wall of separation.

Examples:

(1) Surface condenser

(2) Economizer

(3) Superheater

(ii) DIRECT CONTACT TYPE HEAT EXCHANGER

In this type of heat exchanger, both hot & cold fluids physically mix up with each other & exchange heat.

Example:

 (1) Cooling Tower

 (2) Jet condenser

CLASSIFICATION OF  HEAT EXCHANGER ON BASIS OF RELATIVE DIRECTION:

(i) PARALLEL FLOW HEAT EXCHANGER

In this heat exchanger, both Hot & Cold Fluid travel in the same direction parallel to each other.

(ii) COUNTER FLOW HEAT EXCHANGER

In this heat exchanger, Hot & Cold Fluid travel in the opposite direction parallel to each other.

 

(iii) CROSS FLOW HEAT EXCHANGER

In this heat exchanger, Hot & Cold Fluid travel in perpendicular direction with respect to each other.

TEMPERATURE PROFILES OF HOT AND COLD FLUIDS:

(i) PARALLEL FLOW HEAT EXCHANGER

(ii) COUNTER FLOW HEAT EXCHANGER

The variation of ΔT with respect to x is much more pronounced in parallel flow heat exchanger as compared to that in counter flow heat exchanger.

 

LOGARITHMIC MEAN TEMPERATURE DIFFERENCE (LMTD) OF HEAT EXCHANGER

Logarithmic mean temperature difference is that constant temperature difference (maintained throughout heat exchanger) which would give same amount of heat transfer.

Q = U A ΔT_m

Where,

Q = total Heat Transfer Rate between hot & cold fluid

U = Overall Heat Transfer coefficient

ΔT_m = Logarithmic Mean Temperature Difference between hot and cold fluid

A = Total Heat Transfer Area of Heat Exchanger

(i) LMTD OF PARALLEL FLOW HEAT EXCHANGER

At x = 0, ΔT = ΔT_i = T_hi – T_ci

At x = L, ΔT = ΔT_e = T_he - T_ce

(ii) LMTD of COUNTER FLOW HEAT EXCHANGER

 At x = 0, ΔT = ΔT_i = T_hi – T_ce

At x = L, ΔT = ΔT_e = T_he – T_ci

 

For the same inlet & exit temperature of hot & cold fluids, The value of LMTD for counter-flow heat exchanger is more than that for parallel flow heat exchanger.

LMTD FOR CROSS FLOW HEAT EXCHANGER:

LMTD for cross-flow heat exchanger can be obtained as

Where, F = correction factor,

 

 SPECIAL CASE REGARDING LMTD

 When one of the fluids is undergoing change of phase like in steam condenser or evaporator or steam generator then,

Steam condenser:

(ΔT_m)_{parallel flow} = (ΔT_m)_{counter flow}

 

EFFECTIVENESS OF HEAT EXCHANGER

It is defined as the ratio between actual heat transfer rate that is taking place between hot & cold fluids to the maximum possible heat transfer rate that can occur between them,

q_actual = Rate of enthalpy change of either fluid

q_actual = m_h C_ph (T_hi – T_he) = m_c C_pc (T_ce – T_ci)

q_max = maximum possible heat transfer rate= (m C_p)_small × (T_hi – T_ci)

Where (m C_p)_small  is the smaller capacity rate between hot & cold fluids.

 

Number of Transfer Units (NTU)

It is defined as the ratio between product of UA & small capacity rate between hot & cold fluids.

NTU being directly proportional to the area of the heat exchanger indicates overall size of the heat exchanger.

Capacity Rate Ratio (C):

 

C will become zero when one of the fluids is undergoing change of phase like steam condenser.

For any Heat Exchanger, ϵ = f (NTU, C)

 Effectiveness for the parallel flow heat exchanger:

Effectiveness for the counterflow heat exchanger:

 SPECIAL CASES

CASE 1: when one of the fluids is undergoing change of phase, then C is equal to zero.

Hence,

 

CASE 2: The other extreme value of C=1, when both hot & cold fluids have equal capacity rates (m_h Cp_h = m_c C_pc)