Bissoy.com
Doctors Medicines MCQs Q&A

In a heat exchanger, it is observed that ΔT1 = ΔT2, where ΔT1 is the temperature difference between the two single phase fluid streams at one end and ΔT2 is the temperature difference at the other end. This heat exchanger is

In a heat exchanger, it is observed that ΔT1 = ΔT2, where ΔT1 is the temperature difference between the two single phase fluid streams at one end and ΔT2 is the temperature difference at the other end. This heat exchanger is Correct Answer a counter flow heat exchanger

Explanation:

In case of the counter-flow heat exchanger when the heat capacities of both the fluids are the same.

i.e. ṁhch = ṁccc

[ alt="565d36f803282114ca1e5acd 1" src="//storage.googleapis.com/tb-img/production/16/10/565d36f803282114ca1e5acd_1.png" style="height: 173px; width: 400px;">

 

Q = ṁhch(Th1 – Th2) = ṁccc(Tc2 – Tc1)

⇒ (Th1 – Th2) = (Tc2 – Tc1)

⇒ (Th1 – Tc2) = (Th2 – Tc1)

⇒ ΔT1 = ΔT2

[ alt="26 June 1" src="https://storage.googleapis.com/tb-img/production/19/08/26%20June_1.png" style="width: 170px; height: 49px;">

For parallel flow heat exchanger,  ΔT1 will always be greater than ΔT2.

Related Questions

A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is
The following question consists of six sentences of a passage. The first and the sixth sentences are given in the beginning as S1 and S6. The middle four sentences in each have been jumbled up and labelled P, Q, R and S. You are required to find the proper sequence of the four sentences and mark your response accordingly. S1: A single device can heat fluids without requiring an electrical element. S6: Because there is no electrical element, there is no risk of fire, so the system is suitable for dangerous environments. P: A heat exchanger transfers heat from the central cavity to an air heater, a water heater or an industrial processor. Q: It has a container like the crankcase of a car’s engine, which contains the fluid to be heated. R: Compression and friction at the nozzles heat the fluid so that the temperature in the central -cavity rises steadily. S: A motor and pulley inside the container turn a rotor wheel, which in turn forces the fluid again and again through narrow nozzles into a central cavity. The proper sequence should be
Which of the following statements about Printed circuit heat exchanger are correct? Statement 1: Printed circuit heat exchanger is an example for direct heat exchanger. Statement 2: It has high heat transfer surface area per unit volume of the exchanger.
For a counter current heat exchanger with Tih = 80°C, T°c = 60°C, T°h = 50°C and Tic = 30°C, and the temperature difference between the two streams being the same everywhere along Z, the direction of flow of hot fluid. The temperature profile should satisfy
A cold fluid (specific heat 2.95 k J/kg K) at 10 kg/min is to be heated from 25 degree Celsius to 55 degree Celsius in a heat exchanger. The task is accomplished by extracting heat from hot water (specific heat 4.186 k J /kg K) available at mass flow rate 5 kg/min and inlet temperature 85 degree Celsius. Identify the type of arrangement of the heat exchanger
Forced air flows over a convection heat exchanger in a room heater, resulting in a convective heat transfer coefficient 1.136 k W/m2 K. The surface temperature of heat exchanger may be considered constant at 65 degree Celsius, and the air is at 20 degree Celsius. Determine the heat exchanger surface area required for 8.8 k W of heating
Which of the following statements is/are correct with respect to a Scott-connected transformer? I. It can do 3-phase to 2-phase conversion II. It can do 2-phase to 3-phase conversion III. It can do 2-phase to 4-phase conversion IV. It can do 3-phase to 4-phase conversion
Plate type heat exchangers have less surface area as compared to a similar Shell and Tube heat exchanger. A Shell and Tube Heat Exchanger of equivalent area weigh six-seven times less than a Plate Type heat exchanger.
The network formed by resistors and capacitors for modifying the rate of change of gain and the phase shift is called a compensating network. Which of the following statements are not correct ? (A) The main purpose of a compensating network is to modify the performance of op-amp ciruit over the desired frequency range (B) There are two types of op-amps : internally compensated and externally compensated (C) 741 C is an externally compensated op-amp while 709 C is internally compensated op-amp (D) The phase lag and phase lead are most commonly used compensating networks in op-amps (E) Phase lag contributes a positive phase angle and phase lead a negative phase angle Choose the most appropriate answer from the options given below : 
Bernoulli's equation for fluid flow is derived following certain assumptions. Out of the assumptions listed below, which set of assumptions is used in derivation of Bernoulli's equation?
1. Fluid flow is frictionless & irrotational
2. Fluid flow is steady
3. Fluid flow is uniform & turbulent
4. Fluid is compressible
5. Fluid is incompressible