EPRI Heat Transfer & Fluid Flow Practice Test

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• What happens to cycle efficiency if the condenser vacuum is increased?
• Bubbles in bulk boiling exist as what type of liquid mixture?
• Saturation conditions of a substance are determined by which pair of properties?
• What do bubbles do in local or sub-cooled nucleate boiling?
• Which type of properties includes viscosity, electrical resistance, thermal conductivity, specific volume, pressure, and temperature?
• What cycle process has constant entropy?
• Filling of a voided line (column rejoining) is identified as a cause of water hammer. Which option represents the official cause?
• Which property is used to describe both the amount of heat transferred and the temperature at which it is transferred?
• Which pool boiling region is described by steam bubbles coalescing at the heated surface to form a steam blanket and eliminating convective heat transfer?
• Which describes an open system?
• Natural bodies of water chemistry must be known & intended service operation of ___________?
• Volume, mass, and energy are examples of which property type?
• What is the absolute zero on the Kelvin scale according to the material?
• To prevent water hammer, pumps are started at what condition?
• Which heat transfer mode involves energy transported by electromagnetic radiation and does not require a medium?
• Which option best represents the official cause of water hammer when hot water enters a low pressure line?
• Saturation depends on which two properties?
• Quality is defined as x = 1 - M. In this relationship, what does M stand for?
• When starting centrifugal pumps, what should be true about the discharge valve?
• For HXR backup trains or essential service water systems, tubes must be resistant to attack under what condition?
• In steady, incompressible flow, which equation relates pressure, velocity, and elevation head along a streamline?
• In which flow do fluid particles move in parallel or concentric layers with minimal mixing between layers?
• In which component is the energy balance described by q = h2 - h1?
• When one pump discharges into the suction of another pump, this is called which configuration?
• What is the term for the process of filling a piping system from the lowest point, using high-point vents to release air and closing vents when water fully fills the system?
• Which Reynolds number range is associated with turbulent flow according to the material?
• A substance that deforms continuously under shear stress is best described as a:
• The reciprocal of density is what property?
• What is the relationship between condenser pressure and cycle efficiency when condenser vacuum increases?
• Which option lists the freezing point of water in Rankine as 491.67?
• Which law states that energy is neither created nor destroyed and that energy entering a process equals energy stored plus energy leaving?
• Which term describes the amount of liquid present in a wet vapor mixture?
• Radiation heat transfer can occur without any medium. Which statement is true?
• For a condenser, the general energy equation relating heat transfer to enthalpy change is which?
• Which equation includes four forms of energy: Potential Energy, Kinetic Energy, Flow Energy, and Internal Energy?
• In power plant contexts, which equipment serves as an indirect contact heat exchanger such as steam condensers and feedwater heaters?
• What term describes the condition where adding heat to a liquid causes it to vaporize at the same temperature rather than increasing in temperature?
• For a boiler, the general energy equation relating heat transfer to enthalpy change is which of the following?
• What must be prevented during heat up or cooldown of systems?
• No heat engine, either actual or ideal, operating in a cycle can convert all the heat supplied into mechanical work.
• What type of heat exchanger involves phase change in the cooling or heating fluid?
• Which unit is stated for density in the material?
• In piping contexts where steam pocket collapse occurs, which option is identified as the water hammer cause?
• Preventable actions for pump runout include selecting correct pump size, throttling discharge, creating minimum static head, and installing an alarm. These actions are intended to prevent which condition?
• ______ water usually configured on the tube side?
• What cycle process has constant pressure?
• Which is an example of convection?
• In the Net Suction Head equation Hs = hs + hv + hp - hf, which term represents the velocity head?
• Which heat exchanger type consists of tubes containing one fluid and a shell containing another fluid, with the shell forming the outer surface?
• In the Net Suction Head expression Hs = hs + hv + hp - hf, which term represents the friction head?
• Substances possess several microscopic forms of energy due to rotation, vibration, translation, and interactions among ______ of the substance.
• ΔT_lm in the heat transfer context stands for what?
• Identify the flow type described by: no bubbles, forced convection, single-phase flow, located at the very bottom of the coolant channel.
• Which list correctly names the four regions of the pool boiling curve?
• What happens to cycle efficiency if condensate depression is reduced?
• Which heat transfer mode is primarily described by energy transfer through electromagnetic waves?
• Identify the flow type described by: bubbles form on the wall but do not collapse in the coolant stream, bulk coolant is at saturation temperature, bulk boiling occurs but bubbles are not yet coalescing, low quality.
• Which of the following is NOT a form of energy in the General Energy Equation?
• Which option matches the boiling point of water in Kelvin as 373.15?
• Which flow regime is characterized by bulk boiling occurring but bubbles are NOT yet coalescing?
• Which type of heat exchanger transfers heat by direct physical contact in which heat and mass are transferred as the fluids mix?
• Which region is described as the boiling crisis where heat transfer is primarily by conduction and radiation through a steam layer?
• In local or sub-cooled nucleate boiling, where do steam bubbles form?
• As the amount of water in a mixture decreases, which quantity increases?
• What action should be taken when opening and closing system valves to prevent water hammer?
• What is the term for the mass per unit volume of a substance?
• HXR tubes are commonly made from which materials to resist seawater corrosion?
• TDH is defined as which expression?
• A change of phase may or may not occur with?
• What condition prevents cavitation in a deadheaded pump?
• In the context of pump operation, which term describes the process of filling the pump with liquid and removing all air?
• Which quantity is defined as the force per unit area exerted by a system on its surroundings?
• Identify the flow type described by: bubbles coalesce to form slugs of vapor, void fraction is significant, begins below core midplane in high powered channels, quality is increasing.
• When developing a pump performance curve, what should be considered?
• In a turbine cycle, an example is given for which pump arrangement?
• Which term describes the maximum heat flux before boiling transitions to another regime?
• What are any two independent properties that can be used to obtain the remaining properties?
• Cavitation occurs when which condition is satisfied?
• In the described series pump arrangement, from which source does the residual heat removal pump take suction?
• Which pool boiling curve region corresponds to heat flux continuing to increase and reaching a maximum, known as Departure from Nucleate Boiling?
• Which heat exchanger is described as occasionally used in power plants, a replacement for shell and tube when thermal duty increases, with counterflow types and plates instead of tubes to transfer heat?
• Identify the four forms of energy included in the General Energy Equation.
• Which of the following is not one of the three basic phases of matter?
• What is the absolute zero on the Rankine scale according to the material?
• The average force of the fluid molecules on a wall per unit area is called what?
• Which option best represents the official cause of water hammer in voided line scenarios?
• What is the boiling point of water in Kelvin?
• Which law quantifies radiant energy transfer and includes a factor for emissivity, surface area, and temperature to the fourth power?
• Steam and water counterflow in a horizontal pipe is described. Which option represents the cause of water hammer for this scenario?
• If the moisture content M equals zero, what is the steam quality x?
• Hot water entering a low pressure line (low pressure discharge) is described. Which option represents the cause of water hammer for this scenario?
• Quality of 100% corresponds to which statement about the steam?
• Which equation determines the required heat transfer surface area to achieve a given heat transfer rate, accounting for losses with U and the inlet/outlet temperatures?
• In a steady flow with constant density, the continuity equation reduces to which relation?
• Cavitation occurs when local pressure drops below what?
• In a deadheaded pump, what happens to the energy transferred to the fluid if the fluid is not leaving the casing?
• What is the boiling point of water in Fahrenheit?
• In which region is the heat transfer mechanism unfavorable but increases with larger temperature difference?
• What is the fluid defined as the ratio of its density to the density of water at a specified temperature called?
• Which description defines a closed system?
• Which region is the second region of the pool boiling curve?
• The reciprocal of density is called what?
• What is the action called when drain valves and high point vents are opened to drain the system?
• Which value is listed as the absolute zero for the Fahrenheit scale in the material?
• What is the boiling point of water in Celsius?
• Before starting a pump, what should be ensured to reduce water hammer risk?
• If a property changes with the amount of material, it is classified as which type?
• Priming is defined as which process?
• In pump head terminology, Hd represents which head?
• What is the term for a phase change that occurs without a temperature change?
• Which component provides end support for HXR tubes?
• Which heat transfer mode involves energy flowing through a medium due to a temperature gradient within the medium?
• In which component is the energy balance described by w = h2 - h1?
• If steam is admitted to the shell side of a feedwater heater before the tube side flow path is opened, what happens to the pressure inside the trapped liquid?
• In seawater service, heat exchanger tubes must withstand corrosion when exposed to high chloride concentrations. Which degradation mechanism is the primary concern?
• What are the types of indirect contact heat exchangers?
• Which process is described as having constant entropy in the material?
• A quantity of matter that is homogeneous throughout is called a
• Which process describes a constant enthalpy condition?
• In a system with steam and water counterflow, which option represents the water hammer cause?
• Which diagram is commonly used for steam states above 50% quality and the superheated region?
• What are the three basic phases?
• Which property remains the same when the size of the system changes and does not depend on mass?
• The sudden surge in pressure or liquid velocity within a piping system caused by rapid start/stop of flow, valve action, or steam condensation is known as?
• Which convection results from density gradients developed in the fluid due to temperature differences and does not involve external devices moving the fluid?
• Which unit is used to measure pressure?
• Which region features the heat flux reaching a local minimum and then increasing again?
• What is the freezing point of water in Rankine?
• The description given describes which concept: energy added as heat to a working fluid, its passage through a turbine, and electricity generation in a nuclear plant?
• If a plant needs to boost pressure while maintaining the same flow, which arrangement would be preferred?
• What is vapor heated beyond a saturate state?
• Which term describes a recurring series of thermodynamic processes used to transform energy into a useful effect?
• Weight per unit volume (density times acceleration due to gravity) is called which term?
• When are high point vents closed during filling?
• In which region do discrete vapor bubbles form and depart from the surface as heat flux increases, but a continuous film has not yet formed?
• Which thermodynamic quantity is equivalent to the total heat content of a system?
• Which equation expresses the First Law balance as Energy In = Energy Out + Energy Stored?
• In the equation Q = UAΔT_lm, what does U denote?
• What term describes when a pump runs with little or no flow?
• Specific volume can also be defined as?
• In pump energy terms, hv represents which type of head?
• For a turbine, which expression represents the shaft work in terms of enthalpy?
• In the context of the General Energy Equation, Flow Energy is defined as FE = PV. What do P and V represent?
• In the Net Discharge Head equation Hd = hd + hv + hp + hf, which term is the friction head?
• Which temperature scale uses 212 as the boiling point of water?
• DNBR is the ratio of which two heat flux quantities at a location?
• Two or more pumps discharging into the same system produce which configuration?
• In which component is the energy balance described by q = h1 - h2?
• Integrated curves are used to accomplish what?
• What type of heat exchanger flow path has two fluids flow perpendicular to each other?
• Water hammer is primarily caused by which type of action in the piping system?
• What is the term for the point of maximum heat flux, also known as the critical heat flux?
• DNBR stands for Departure from Nucleate Boiling Ratio.
• What is the term for the pump arrangement where one pump feeds a higher head pump?
• Which type of property depends on the mass of the sample?
• What is it called when a substance experiences a change in temperature but not a change in phase?
• What diagram is used when the quality is above 50% and for superheated steam?
• When the liquid is at or above saturation temperature, what process occurs?
• Which value is listed as the absolute zero for the Celsius scale in the material?
• In Fourier's law, qx = -k A (dT/dx), the heat transfer rate is proportional to which of the following?
• In a shell-and-tube heat exchanger, which component forms the outer surface that contains the shell-side fluid?
• What are the four forms of energy included in the General Energy Equation?
• Which regime consists of steam with entrained moisture droplets and is typically observed only under LOCA conditions in PWRs?
• What is the role of a tube sheet in a heat exchanger?
• During boiling at saturation, what happens to temperature as heat is added?
• Which type of pumps have higher flow but similar head?
• What type of heat exchanger flow path has tube side and shell side fluids flow parallel and in same direction?
• In a closed system, which factors affect pressure?
• From which point is it desirable to fill the system?
• What property is defined as mass per unit volume?
• Two-phase flow refers to a mixture of which two phases?
• What is the most common/desirable heat exchanger flow?
• According to the Second Law, you cannot have a cycle with 100% efficiency.
• Pressure drop and heat transfer rates are ______ for turbulent flow.
• For a pump, which expression represents the shaft work in terms of enthalpy?
• Which heat exchanger type is bent into a U shape with the inlet and outlet on the same end and a divider plate separating inlet from outlet?
• How can the number of tube-side passes be increased in a multi-pass heat exchanger?
• What causes natural convection flows in a fluid?
• Entropy is described as a thermodynamic property related to the amount of heat transfer and the temperature at which transfer occurs.
• If the moisture content M is 0.25, what is the corresponding quality x using x = 1 - M?
• According to the Pump Affinity Laws, which relationships are correct?
• Which of the following is a recommended method to prevent water hammer when starting large-capacity pumps?
• Which condition can cause water hammer?
• The heat transfer rate Q is commonly expressed in which unit in heat exchanger calculations?
• What measure involving steam lines is suggested to prevent water hammer?
• Head-Flow Curves illustrate which relationship?
• When heat transfer on a control rod occurs at the cladding outer surface, the dominant mechanism is
• In a pressurized water reactor, which limit must never be exceeded to prevent overheating?
• Why are high point vents opened during filling?
• Which region is the first region of the pool boiling curve?
• The operating point of a pump is found at the intersection of which curves?
• System resistance curves include which elements for a given speed and impeller size?
• Which law governs radiant heat transfer and shows dependence on the fourth power of temperature?
• Which flow regime is defined by vapor forming a continuous phase in the space between fuel elements, with liquid moving along the walls?
• What cycle process has constant enthalpy?
• Which type of heat exchanger involves phase change of the fluids?
• What is the boiling point of water in Rankine?
• What term describes a region of uniform properties within a material system?
• When HXR tubes operate in environments with high silt or suspended solids, they must be resistant to which combined effect?
• Which flow regime begins below the core midplane in high powered channels and features significant vapor pockets?
• Which region is the fourth and final region of the pool boiling curve?
• A change of ______ will always occur with a change of phase.
• What occurs when the entire liquid is at or above saturation temperature for the existing pressure?
• Component coolers, steam surface condensers, feedwater heaters, and steam generators in PWR nuclear plants are examples of which heat exchanger type?
• Which of the following is an example of an extensive property?
• In Transition Boiling, which heat transfer modes contribute?
• Which option represents the official cause of water hammer in rapid valve actuation scenarios?
• Which value is listed as the absolute zero for the Rankine scale in the material?
• In a series pump configuration, what happens to head and flow?
• The logarithmic mean temperature difference (LMTD) is represented by which symbol in the overall heat transfer equation?
• What occurs when a hot surface is in contact with a liquid that is below the liquid's saturation temperature for the current pressure?
• Which statement best characterizes the Best Efficiency Point (BEP)?
• The DNBR margin used to maintain the PWR thermal limit is which value?
• Which heat exchanger type has the fluid inside the tubes traveling from one end to the other without changing direction?
• What does Available Net Positive Suction Head (NPSHA) represent?
• Identify the flow type described by: bubbles form at the wall but collapse in the bulk coolant, no net vapor generation, very small void fraction, and occurs above the forced convection region.
• In heat exchanger terminology, what term describes a configuration where the working fluid remains entirely in a single phase?
• Which term stands for the threshold where nucleate boiling ends and heat transfer becomes limited by a vapor layer?
• What do the bubbles do in bulk boiling?
• Fourier's Law expresses the conduction heat transfer rate as qx = -k A (dT/dx). Which quantity is the material's insulating property in this law?
• In which region does surface dry-out occur, leading to film boiling?
• Which convection type uses external devices such as pumps or fans to induce bulk fluid motion and typically results in high heat transfer rates?
• What marks the end of nucleate boiling and the beginning of decreased heat transfer?
• Which option best represents the official cause of water hammer in valve slam scenarios?
• What is the primary purpose of external fin tubes in heat exchanger design?
• Plate and Frame heat exchangers are described as a replacement for shell and tube when higher thermal duty is required.
• The pump head equation accounts for differential pressure head, velocity head, elevation head, and head losses; which equation is this?
• Moisture content is defined as the mass of liquid divided by the sum of the masses of liquid and vapor. Which expression represents this definition?
• What is the term for the temperature at which water first begins to vaporize into steam at a given pressure?
• In the overall heat transfer equation, which symbol represents the effective heat transfer surface area?
• What cycle is defined as a recurring series of thermodynamic processes used for the transformation of energy to produce a useful effect?
• Which law establishes energy cannot be created or destroyed and the energy balance includes energy in, energy out, and energy storage?
• What is the absolute zero on the Celsius scale according to the material?
• Which term describes the amount of vapor present in a liquid–vapor mixture?
• Which equation is used with the heat transfer equation to monitor heat exchanger performance?
• Identify the flow type described by: vapor forms a continuous phase in space between fuel elements, slower moving liquid travels along the walls, experienced near channel exits in higher powered channels.
• What depends on both the properties of the fluid and the nature of the flow (laminar or turbulent)?
• Which device protects plant components from overpressure?
• What is the overall purpose of residual heat removal pumps in a plant?
• Which of the following are examples of direct contact heat exchangers?
• What is the sum of energy in a substance called?
• When heat transfer on a control rod takes place from the center of the fuel to its outer surface, the dominant mechanism is
• In which region does the surface experience rapid temperature rise and transition from nucleate boiling to film boiling?
• What happens to cycle efficiency if the feedwater heating increases?
• Which device prevents overpressure by releasing fluid when the pressure exceeds a set limit?
• Which type of flow is described as irregular with a lack of clear streamlines and no observable pattern?
• Which quantity represents the fraction of the total mass that is in vapor form in a liquid–vapor mixture?
• Which unit is used for density in the material?
• Which statement best describes indirect contact heat exchangers compared to direct contact?
• Which statement about water hammer prevention is true?
• What is the freezing point of water in Kelvin?
• Which factor is critical in selecting the material for heat exchanger components?
• True or False: Counterflow arrangement generally provides a higher average driving temperature difference than parallel flow.
• Which temperature scale assigns the freezing point of water as 0 degrees?
• What happens to cycle efficiency if steam temperature at the turbine entrance increases?
• Which region is characterized by dry-out of the heated surface and the formation of a stable vapor film?
• What type of heat exchanger is most commonly used in power plants?
• Friction between the flowing fluid and the surface is __________ for turbulent flow.
• The thermodynamic condition of a substance defined by two or more independent thermodynamic properties is called
• What happens to cycle efficiency if the cooling water system flow rate increases?
• If a plant needs to ramp up flow without changing system head, which pump arrangement is most appropriate?
• Parallel pumps are useful when varying flows are required because you can use which options?
• Which region involves heat flux increasing and liquid above saturation leading to bulk boiling with bubbles rising to the surface, or forced convection remaining in liquid?
• In the overall heat transfer equation, the thermal duty or heat transfer rate is denoted by which symbol?
• Which option would illustrate water hammer due to column rejoining after a void?
• What is the freezing point of water in Fahrenheit?
• In the Net Discharge Head equation Hd = hd + hv + hp + hf, what does hd denote?
• If the system has been in extended shutdown, what is advised about pump discharge valves?
• Which is an example of a closed system in a nuclear plant?
• What is a primary advantage of using parallel pumps over a single larger pump?
• Quality of 100% corresponds to which state?
• An automobile radiator, where coolant is pumped through tubes, is an example of which convection type?
• What term measures a fluid's resistance to shear and deformation, i.e., its resistance to flowing?
• Which law applies to conduction?
• Which temperature scale has the boiling point of water at 373.15?
• Which heat transfer mode occurs when thermal energy is transported away from a system boundary by a moving medium?
• During maintenance, what procedure is used to prevent equipment operation?
• In the overall heat transfer equation, which symbol denotes the overall heat transfer coefficient?
• What is the effect of internal grooves on HXR tubes?
• In a car cooling system, where engine coolant is pumped through radiator tubes, which convection type is demonstrated?
• What is the form of the overall heat transfer equation?
• Which heat exchanger type contains divider plates or pass partitions in the channel that separates the fluid entering and leaving the HX, and the number of passes for the tube side fluid can be increased by divider plates on the channel head?
• What term is used for the total energy content of a substance?
• Which region is the third region of the pool boiling curve?
• What is the equation for enthalpy?
• Which option describes the event associated with steam pocket collapse in piping systems?
• Pump Runout refers to which of the following?
• Which option represents the official cause of water hammer when a voided line column rejoining occurs?
• What term describes the protection that prevents excessive pressure when steam is admitted to the shell side before the tube side is opened?
• Which is an example of an open system?
• What term refers to the minimum fluid energy at the pump inlet specified by the manufacturer?
• Which option represents the general cause of water hammer?
• Which region corresponds to the initial application of heat and the formation of bubbles at nucleation sites?
• What ratio represents the critical heat flux divided by the actual heat flux at a location?
• What type of heat exchanger does cooling/heating fluid REMAIN in gaseous or liquid phase?
• Identify the flow type described by: consists of steam with some drops of entrained moistures, exists in PWRs only under abnormal conditions such as LOCA.
• What is the absolute zero on the Fahrenheit scale according to the material?
• In which region does forced flow occur with convection still contributing but greatly reduced?
• Which cycle process has constant temperature?
• In the form p1A1v1 = p2A2v2, which fundamental equation is being described?
• External devices that produce bulk fluid motion are used to generate which type of convection?
• Rapid valve actuation in a piping system is identified as a cause of water hammer. Which option represents the official cause?
• In which component is the energy balance described by w = h1 - h2?
• What is the freezing point of water in Celsius?
• Which statement about heat transfer coefficients in convection is correct?
• Which statement best describes laminar flow?
• Which cycle process involves no loss or gain of heat?
• Gas binding in a pump system is most commonly caused by which of the following?
• Which heat exchanger flow path maintains a higher average temperature difference between the two fluids when they flow in opposite directions?
• In a nuclear power plant, the heat input is generated by what?
• Which region is described as beginning with subcooled natural convection and bubbles moving away from the heated surface and collapsing since the liquid is below saturation?
• The selection of which material is based on the cooling water chemistry, entrained particulates in the water, and expected stagnant conditions?
• Natural convection typically yields what heat transfer rate compared with forced convection?
• The feature that creates multiple passes in a heat exchanger channel by dividing the flow is called divider plates or pass partitions.
• What is the volume per unit mass?
• Which law describes convection heat transfer?
• Shell side is a __________ system where chemistry is monitored and controlled.
• Which term describes degradation of a heat exchanger's performance due to fouling and related issues?
• What type of heat exchangers have no physical contact between the two fluids and are separated by a metallic tube wall boundary?
• Pressurized water entering a vertical steam-filled pipe (steam pocket collapse) is described. Which option represents the cause of water hammer for this scenario?
• What type of property is independent of the amount of material present?
• If deadheaded operation continues, what may occur?
• Heat flux will reach the DNB value again during which phenomenon?
• Which region is associated with the formation of a vapor film that insulates the surface?
• Which of the following is not an indirect contact heat exchanger?
• Which material is least suitable for HXR tubes in seawater service?
• What is the general objective of proper filling and venting practices in piping systems?
• What term describes the science that studies energy transfer and the behavior of systems undergoing state changes?
• What is the measure of how well a material transfers heat, which can vary with temperature?