Chemical Engineering - MCQ Practice Questions

Which of the following is the SI unit of thermal conductivity?

In heat conduction through a composite wall, the overall heat transfer rate is determined by which principle?

What is the Biot number (Bi) used to determine in transient heat conduction?

For fully developed laminar flow in a circular pipe with constant wall heat flux, which Nusselt number (Nu) is approximately correct?

Which dimensionless number represents the ratio of buoyancy forces to viscous forces in natural convection?

In a counter-current heat exchanger with equal heat capacities, what is the maximum possible effectiveness?

The Number of Transfer Units (NTU) is defined as which of the following?

For a long thin fin with adiabatic tip condition, the fin efficiency is given by:

Which of the following best describes the behavior of thermal conductivity with temperature for most metals?

In a parallel plate channel with constant heat flux q'' on both walls, what is the thermal entrance length relationship with hydrodynamic entrance length?

The log mean temperature difference (LMTD) correction factor F is required primarily for which configuration?

For turbulent flow in smooth pipes (Pr > 0.6), which correlation is most commonly used?

The thermal diffusivity (α) has dimensions of which of the following?

In a shell-and-tube heat exchanger (1 shell pass, 2 tube passes), the effectiveness is lower than counter-current primarily because:

For a flat plate solar collector with selective coating, which of the following is most desirable?

The Graetz number in laminar heat transfer represents:

For natural convection from a vertical isothermal plate in air, which correlation applies best?

In unsteady-state conduction with Bi << 0.1, what assumption is valid?

Which statement best describes radiation heat transfer in participating media?

For a microfin tube (enhanced surface), the heat transfer improvement comes primarily from: