Description : With neat sketch explain the construction and working of heat exchanger used for handling corrosive liquid.
Last Answer : Graphite block heat exchanger: Graphite heat exchangers are well suited for handling corrosive fluids. Graphite is inert towards most corrosive fluids and has very high thermal conductivity. Graphite being ... vertical faces direct the service fluid through the exchanger in a cross flow.
Description : Draw a neat labelled diagram of 1-2 shell and tube heat exchanger.
Last Answer : 1-2 shell and tube heat exchanger:
Description : Name any four types of shell and tube heat exchanger.
Last Answer : Four types of shell and tube heat exchanger: 1. Fixed tube heat exchanger 2. Floating head heat exchanger 3. U- tube type heat exchanger 4. Kettle/ Reboiler type heat exchanger
Description : Explain the type of multiple effect evaporator feed arrangement used for handling viscous liquid.
Last Answer : Backward feed arrangement If the liquid is very viscous, then we have to adopt backward feed arrangement. In this arrangement, the feed solution and vapour flow is in opposite direction. Fresh feed is ... Not very common as it need pump. At low values of feed temperature higher economy.
Description : Define the following terms : (i) absorptivity (ii) reflectivity (iii) transmissivity (iv) emissivity
Last Answer : Absorptivity: It is the fraction of total incident radiation which is absorbed by a body. Reflectivity: It is the fraction of total incident radiation which is reflected by a body. Transmissivity: It ... total emissive power of a body to emissive power of a black body at the same temperature.
Description : Give expression for the following and explain the terms involved. (i) Nusselt number (ii) Prandtl number
Last Answer : 1. Nusselt NumberNNU= hd/k h – fim heat transfer coefficient d - diameter of pipe k – thermal conductivity of fluid 2. Prandtl Number NPR -Cp µ/k Cp– specific heat of fluid µ - viscosity of fluid k – thermal conductivity
Description : Calculate the rate of heat transfer by radiation from an unlagged steam pipe, 50 mm o.d. at 393K to air at 293K emissivity e = 0.9.
Last Answer : Rate of heat transfer by radiation Assume length of pipe = 1 m
Description : Give the unit of overall heat transfer coefficient in SI and MKS.
Last Answer : Unit of overall heat transfer coefficient 1. In SI : W/m2K 2. In MKS : kcal/hr m2K
Description : Define film heat transfer coefficient.
Last Answer : Film heat transfer coefficient: Film heat transfer coefficient h is defined as the quantity of heat transferred in unit time through unit area at a temperature difference of 10 between the surface and surrounding.
Description : Define steady state heat transfer.
Last Answer : Steady state heat transfer: Heat transfer where temperature remains same with respect to time and the rate of heat transfer does not vary with time.
Description : Explain Wilson plot.
Last Answer : Wilson Plot: The Wilson plot method was developed by Wilson in 1915 to evaluate the convection coefficients in shell and tube condensers for the case of a vapour condensing outside by means of ... resistance and the remaining thermal resistances participating in the heat transfer process.
Description : Explain Kirchhoff’s Law with its mathematical expression in detail.
Last Answer : Kirchoff's law of radiation: Kirchoff's law: It states that at equilibrium temperature, the ratio of total emissive power of any body to absorptivity depends only upon the temperature of the body. ... respectively. At thermal equilibrium, absorption and emission rates are equal, thus,
Description : With a neat diagram explain the construction of calendria type evaporator.
Last Answer : Calendria type(Short tube) evaporator: Construction: It consists of vertical cylindrical shell incorporating short vertical tube bundle with horizontal tube sheet. Vapour inlet is provided at top ... sheet, while non condensable gas is vented to atmosphere from point near top tube sheet.
Description : Explain the properties of solution that influences evaporation.
Last Answer : Properties of evaporating liquid 1. Concentration: As the concentration increases, the solution becomes more and more individualistic. The viscosity and density increase with solid content. The boiling point of ... is a problem, special materials such as copper, nickel, stainless steel may be used.
Description : Explain the concept of optimum thickness of insulation.
Last Answer : Optimum thickness of insulation: The optimum thickness of an insulation is obtained by purely economic approach. The greater the thickness, the lower the heat loss & the greater the initial cost of ... sum values of heat lost and annual fixed charges) of the insulation is minimum.
Description : Define capacity and economy of evaporator.
Last Answer : The capacity of an evaporator is defined as the number of kilogram of water evaporated per hour. The economy of an evaporator is defined as the number of kilogram of water evaporated per kilogram of steam fed to the evaporator.
Description : Define radiation and give one example.
Last Answer : Radiation: Radiation is transfer of energy through space by electromagnetic waves. If radiation is passing through empty space, it is not transformed into other forms of energy, nor is it diverted from its ... only the absorbed energy that appears as heat. Example: Loss of heat from unlagged pipe.
Description : Heat Transfer Software
Last Answer : The process of heat transfer is used in many industries - the scientific industry, engineering industry and every industry you can possibly think of that uses thermal heat. Because of this, there is a need ... group, so you won't have to go through the hassle of copying information down for others.
Description : Heat Transfer Machines
Last Answer : Heat transfer machines are just the thing you need in order to do heat transfers on your clothing or whatever surface you want to decorate. In order for you to stick designs and precious stones on porous and ... is best. This will also give you an idea of what kind of designs you can choose from.
Description : Heat Transfer Experiments
Last Answer : Heat transfer experiments are basically experiments that deal with temperature, its characteristics and qualities. Heat transfer experiments are done for many purposes, but mainly to do investigations on the ... three are learned, it helps to have a better understanding of heat transfers as well.
Description : In a gas-liquid shell and tube heat exchanger, the (A) Presence of a non-condensable gas decreases the condensing film coefficient (B) Gases under high pressure are routed through the tube side, because high pressure ... water or steam condensate remain localised to the tubes (D) All 'a', 'b' & 'c'
Last Answer : (D) All 'a', 'b' & 'c'
Description : Pick out the wrong statement: (A) The capacity of an evaporator is reduced by the boiling point elevation (B) Corrosive liquid is normally passed through the tubes in a ... recompression evaporator (D) Heat sensitive materials should be concentrated in high pressure evaporators
Last Answer : (D) Heat sensitive materials should be concentrated in high pressure evaporators
Description : Leidenfrost point is a term concerned with the (A) Condensation of the saturated vapor on a cold surface (B) Concentration of a corrosive solution by evaporation (C) Heat transfer between two highly viscous liquids (D) Boiling of a liquid on a hot surface
Last Answer : (D) Boiling of a liquid on a hot surface
Description : Condensing film co-efficient for steam on horizontal tubes ranges from 5000 to 15000 Kcal/hr.m2 .°C. Condensation of vapor is carried out inside the tube in a shell and tube heat ... drop through the exchanger is desired (D) Temperature of the incoming vapor is very high
Last Answer : (B) Supersaturated
Description : Agitated film evaporator is suitable for concentrating __________ liquids. (A) Foaming (B) Viscous (C) Very thin (D) Corrosive
Last Answer : (B) Viscous
Description : Pick out the wrong statement. (A) Packed towers are preferred for vacuum operation, because the pressure drop through the packing is less and they (packings) also lessen the ... of liquid, problem of channelling, loading & flooding is generally encountered in packed towers
Last Answer : (C) Diameter of randomly packed tower is normally more than 1.2 metres
Description : Viscous & heat sensitive liquids are concentrated in __________ evaporators. (A) Open pan (B) Long tube (C) Agitated film (D) None of these
Last Answer : (C) Agitated film
Description : For high efficiency of transfer of power, internal resistance of the source should be?
Last Answer : For high efficiency of transfer of power, internal resistance of the source should be less than the load resistance.
Description : Explain data transfer mechanism in I2C protocol. Compare it with CAN and USB protocol based on bit rate and area of applications.
Last Answer : I2C (Inter-Integrated Circuit): I2C stands for Inter-Integrated Circuit. I2C is a serial protocol. It was developed by Philips Semiconductor. I2C bus have two communication lines. One is serial data ( ... Mbps this is used for lower speed devices. Using USB we can connect upto 127 devices.
Description : Extremely large or small volumes of fluids are generally best routed through the shell side of a shell and tube heat exchanger, because of the (A) Less corrosion problems (B) Flexibility possible in the baffle arrangement (C) Low pressure drop (D) High heat transfer co-efficient
Last Answer : (B) Flexibility possible in the baffle arrangement
Description : Which of the following forced convection heat transfer equation accounts for the liquid viscosity effect for viscous liquids? (A) Dittus-Boelter equation (B) Sieder-Tate equation (C) Nusselt equation (D) None of these
Last Answer : (B) Sieder-Tate equation
Last Answer : By use of thermocouple.
Description : Which of the following thyristors can be used for high frequency of operation? A) TRIAC B) DIAC C) SCR D) GTO
Last Answer : Which of the following thyristors can be used for high frequency of operation? A) TRIAC B) DIAC C) SCR D) GTO
Description : With neat sketch explain four modes of operation of a TRIAC?
Last Answer : Modes of operation of a TRIAC: There are four different operating modes of TRIAC: 1) MT2 and gate are positive with respect to terminal MT1(Mode1) : Here terminal MT2 is positive ... junction P2-N2 is forward biased, current carriers are injected and therefore, the TRIAC is turned on.
Description : What is PLL? Explain its operation with a block diagram.
Last Answer : PLL - A phase-locked loop or phase lock loop is a control system that generates an output signal whose phase is related to the phase of an input signal Block diagram ... to the input frequency. The phase - locked loop goes through three states free running capture and phase lock.
Description : Draw & explain operation of phase detector.
Last Answer : In phase detector, the op-Amp basically acts as a zero crossing detector. If a sine wave is applied at the i/p, we get square wave at the op-Amp o/p (at point ... to two channel of the CRO. The time duration between the pulses corresponding to voltages represent the phase between them.
Description : Draw and explain integrated duration curve used in system operation.
Last Answer : Diagram of integrated duration curve used in system operation: Explanation: Integrated duration curve is obtained from load duration curve. It is drawn in between load on Y-axis in KW/MW and the X- ... a particular time of a day can also be shown on a curve which is called as mass curve.
Description : Explain the operation of UPS with a neat block diagram.
Last Answer : Uninterruptible-Power-Supplies (UPS): A block diagram of UPS system is shown in figure. It essentially consists of four major components: i)Rectifier (or battery charger) ii) ... . Due to fast action requirement, transfer switch can be implemented by fast acting semiconductor devices.
Description : Explain the operation of advanced gas cooled reactor.
Last Answer : Operation:- Carbon dioxide or Helium is the gas used for transferring the heat produced form the reactor core to the Heat exchanger. The gas is pumped through the reactor core at high pressure. In heat ... The AGR was designed to have a high thermal efficiency 40 %. Steam pressure is 162 Kg/cm2
Description : Draw diagram of class A push-pull amplifier and explain its operation.
Last Answer : Class A Push-pull Amplifier: The circuit diagram of class A push-pull amplifier is as shown in the fig.(a). Operation: The resistors R1 and R2 along with Vcc provide the dc biasing so as ... Vcc is applied to the collectors of transistors Q1 and Q2 through the centretapped output transformer.
Description : What is photodiode? Draw the symbol and explain operation of photodiode.
Last Answer : A photodiode is a light detector that converts light into an electrical current. A photodiode is a semi-conductor device, with a p-n junction and an intrinsic layer between p and n layers ... current is independent of reverse bias voltage. Reverse current is mostly depends on the light intensity.
Description : Explain the series and parallel operation of MOSFET. Which is suitable and why?
Last Answer : Series operation of MOSFET: To increase voltage handling capability MOSFETs are connected in series. When the MOSFETs are connected in series each MOSFET should turn on and turn off ... on and turn off time and transconductance. Each MOSFET should share current equally.
Description : Also, highlight the problem faced during parallel operation.
Last Answer : Parallel operation of IGBT: Parallel operation of IGBT is done for obtaining high current rating. Paralleling of IGBT reduces conduction losses and thermal stress. IGBT combines the qualities of ... . IGBTs must share losses equally otherwise IGBT may get failure due to thermal differences.
Description : Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for ... a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature
Last Answer : (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs
Description : Mention The Steps In The Interrupt Driven Mode Of Data Transfer.?
Last Answer : Answer :The steps followed in this type of transfer are as follows: The peripheral device would request for an interrupt. The request acknowledgement for the transfer is issued at the end of ... coordinates by the ISS. Again the Interrupt system is enabled and the above steps are repeated.
Description : How to Write a Job Transfer Request ?
Last Answer : How to Write a Job Transfer Request No matter which type of industry you are in, there may come a point in your career when you would not want to settle for the current position that you have at ... push that your boss needs to finally take notice of the work that you have been doing in the past.
Description : Fuel Transfer Pumps
Last Answer : A fuel transfer pump is used to move fuel from one container to another. These pumps are used to fuel cars, planes, agricultural equipment and other devices. They are typically used to transfer diesel and ... for quicker fueling. These models may cost more, but they will make your job a lot easier.
Description : How to transfer an apartment to a non-residential fund?
Last Answer : Can a private entrepreneur use his apartment as an office? The answer to this question depends on the type of activity. To sew, write poetry, fill out accounting documents, engage in tutoring, write ... is unacceptable. If you are not satisfied with this decision, you can appeal it in court.
Description : Transfer switch
Last Answer : .embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
Description : Maximum Power Transfer Theorem 1
Last Answer : Maximum Power Transfer Theorem 1