Chemical Heat Transfer Quiz 4

In a heat exchanger, floating head is provided to______?

Heat transfer by _____ may not necessarily require the presence of a medium?

In a liquid-liquid heat exchanger, for the same process temperature, the ratio of the LMTD in parallel flow to the LMTD in counter flow is always___________?

In a single evaporator system, the steam economy _________ by creating vacuum in the evaporator?

In case of ______ boiling, the bubbles formed on a submerged hot surface get absorbed in the mass of the liquid?

In a cooling tower, water becomes cool by_________?

In Biot number, the characteristic length used is the ratio of the ________ of the solid?

If a single tube pass heat exchanger is converted to two pass, then for the same flow rate, the pressure drop per unit length in tube side will _________?

In a 1-1 concurrent heat exchanger, if the tube side fluid outlet temperature is equal to the shell side fluid outlet temperature, then the LMTD is__________?

Heat transfer rate described by Fourier?s law will decrease, if the ______ increases?

Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8. Pr n, is not valid, if the value of ___________?

In a gas-liquid shell and tube heat exchanger, the__________?

If the baffle spacing in a shell and tube heat exchanger increases, then the Reynolds number of the shell side fluid__________?

Heat transfer by conduction in the turbulent core of a fluid flowing through a heated pipe is negligible, if the value of Prandtl number is________?

Heat transfer by conduction results due to the transfer of free electrons, kinetic energy & vibrational energy from one molecule to another. Conduction heat transfer cannot take place______?

In a heat exchanger, the rate of heat transfer from the hot fluid to the cold fluid_____?

Heat transfer efficiency leading of energy conservation in a heat exchanger can be achieved by______?

Heat transfer by radiation between two bodies at T1 & T2 and in an ambient temperature of Ta?C depends on______?

In a heat exchanger, one transfer unit means_____?

In a co-current double pipe heat exchanger used for condensing saturated steam over the inner tube, if the entrance and exit conditions of the coolant are interchanged, then the rate of condensation will_____?

If average heat transfer co-efficient is ha and the local coefficient at the end of the plate is hl then in case of heat transfer to a fluid flowing over a flat plate, heated over its entire length_________?

Heat transfer occurs by natural convection because change in temperature causes difference in___________?

In a shell and tube heat exchanger, putting a longitudinal baffle across the shell, forces the shell side fluid to pass ______ through the heat exchanger ?

Heat transfer by natural convection is enhanced in system with___________?

In a single effect evaporator, the economy is_________?

In a boiling curve, the peak heat flux is called the ______ point?

In an interphase heat transfer process, the equilibrium state corresponds to equality of temperature in the two phases, while the condition for equilibrium in an interphase mass transfer process is equality of_____?

If heat transfer rate varies with the time, it is termed as___________?

In a multiple effect evaporator, the effect of boiling point elevation is to________?

In a forward feed multiple effect, the pressure build up will be______?

In a shell and tube heat exchanger, the height of 25 percent cut baffles is equal to (where, D = inside diameter of shell) ?

If the thermal conductivity of a wall material is independent of temperature, the steady state temperature distribution in the very large thin plane wall having steady, uniform surface temperature follows _____ law?

In a parallel flow heat exchanger, if the outlet temperature of hot and cold fluids are the same, then the log mean temperature difference (LMTD) is__________?

Heat transfer rate per unit area is called__________?

In a forward feed multiple effect evaporator unit___________?

If air (a non-condensing gas) is present in a condensing vapor stream, it will _______ the condensation rate of vapor?

Heat transfer in the laminar sub-layer in case of a liquid flowing through a pipe, is mostly by___________?

In a forward feed multiple effect evaporator, the pressure is ______?

In a shell and tube heat exchanger, the shell side fluid velocity can?t be changed by changing the__________?

Heat transfer co-efficient (h1) for liquids increases with___________?

If h1 = inner film co-efficient and /h2 = outer film co-efficient, then the overall heat transfer co-efficient is_________?

If Prandtl number is greater than the Schmidt number, then the______?

In a shell and tube type heat exchanger, the floating tube bundle heat arrangement is used_________?

In case of ________ boiling, the liquid temperature is below the saturation temperature and the boiling takes place in the vicinity of the heated surface?

If the thermal conductivity of a wall material is independent of temperature, the steady state temperature distribution in the very large thin plane wall having steady, uniform surface temperature follows ______ law?

In a shell and tube heat exchanger, square pitch compared to triangular pitch___________?

In a backward feed multiple effect evaporator _____ ?

In an extended surface heat exchanger, fluid having lower co-efficient_________?

In a laboratory test run, the rate of drying was found to be 0.5 x 10-3 kg/m2.s, when the moisture content reduced from 0.4 to 0.1 on dry basis. The critical moisture content of the material is 0.08 on a dry basis. A tray dryer is used to dry 100 kg (dry basis) of the same material under identical conditions. The surface area of the material is 0.04 m2/kg of dry solid. The time required (in seconds) to reduce the moisture content of the solids from 0.3 to 0.2 (dry basis) is________?

In a shell and tube heat exchanger, floating head is used for __________?