Thermal & Fluids - Sample Exam Problems

Practice Exam Designed to be as Close to the Actual Exam as Possible

The information shown on this website is a sample of the material provided in the technical study guide and sample exam. My exams are designed to be as close to the actual PE exam as possible. After each exam, I ask all my customers to provide suggestions on how I can improve my exam. This makes my exam always up to date and an exam that is constantly improving. My exam is a PDF and this is my full time job, so I am able to quickly make changes and issue updates to anyone who purchases the practice exam. I also use a four step method to determine what will most likely be on the PE exam.
First the topics were identified from the official NCEES website. Second, these topics were investigated for key concepts and skills that are commonly used by practicing mechanical engineers. Next, these key concepts and skills were filtered for those that could be tested in roughly 6 minutes per problem. Finally, this practice exam focuses on the principle or application of a skill or concept and not background knowledge of the topic or concept.
This systematic approach to developing sample problems, gives you near actual exam problems for the Mechanical Thermal & Fluids PE Exam. Use this exam to gauge your level of preparedness and to help focus your studying into your areas of need. See the STORE to purchase these items.

Sample Exam Problem 1 - Distribution Systems

The Distribution Systems topic accounts for 9 problems on the PE Exam

A pump pumps 100 GPM through the circuit below. Each valve has an equivalent length of 15 ft. Equipment A has an equivalent length of 25 ft and Equipment B has an equivalent length of 40 ft. What is the amount of GPM through branch A-C and through branch B-C? Assume the same diameter pipe throughout the entire circuit and constant friction factor.



(A) Branch A-C = 63 GPM; Branch B-C = 37 GPM;
(B) Branch A-C = 19 GPM; Branch B-C = 81 GPM;
(C) Branch A-C = 50 GPM; Branch B-C = 50 GPM;
(D) Branch A-C = 75 GPM; Branch B-C = 25 GPM;

Sample Exam Problem 2 - Hydraulic and Fluid Equipment

The Hydraulic and Fluid Equipment topic accounts for 15 problems on the PE Exam

Two compressors are placed in series, with an intercooler inbetween the two compressors. The intercooler cools the air such that the temperature entering the second compressor is the same as the temperature entering the first compressor. The air enters the 1st compressor at a pressure of 14.7 psia. The required pressure at the exit of the 2nd compressor is 500 psia. What is the pressure of the air exiting the 1st compressor, if both compressors have the same pressure ratio?


(A) 39 psia
(B) 86 psia
(C) 176 psia
(D) 257 psia


See the Practice Thermal and Fluids PE Exam for the solution.

Sample Exam Problem 3 - Energy/Power Equipment

The Energy/Power Equipment topic accounts for 8 problems on the PE Exam

A steam power plant has a turbine that has a high pressure of 300 psia and a low pressure of 30 psia. If the condenser pressure is reduced to 14.7 psia and the boiler pressure and maximum boiler temperature remain the same, then which of the following statements is true? Assume an ideal Rankine cycle.


(A) The overall power plant efficiency will remain unchanged.
(B) The total amount of useful work produced by the turbine will decrease.
(C) The entropy of the steam entering the condenser will remain unchanged.
(D) Statements A and C are both true.


See the Sample Thermal and Fluids PE Exam for the solution.

Sample Exam Problem 4 - Cooling/Heating

The Cooling/Heating topic accounts for 6 problems on the PE Exam

A cooling unit cools 4,000 cfm of outside air to 55oF DB, 53oF WB. The outside ambient condition is 87oF DB, 75oF WB. What is the total cooling load required by the air handling unit? Assume that the density of air is 0.075 lbs per cubic foot.


(A) 206,000 BTUH
(B) 297,000 BTUH
(C) 341,000 BTUH
(D) 399,000 BTUH


See the Sample Thermal and Fluids PE Exam for the solution.

Sample Exam Problem 5 - Energy Recovery

The Energy Recovery topic accounts for 5 problems on the PE Exam

75 F, 14.7 psia air enters the open Brayton cycle shown below. The air is compressed to a pressure of 100 psia. Air enters the turbine at a temperature of 1200 F and leaves at a pressure of 14.7 psia and a temperature of 550 F. Assume no air leakages, constant heat capacity, isentropic compressor, 80% effective heat exchanger and isentropic turbine. What is the heat added in the combustion process?



(A) 90 BTU/LBM
(B) 160 BTU/LBM
(C) 200 BTU/LBM
(D) 400 BTU/LBM


See the Sample Thermal and Fluids PE Exam for the solution.

Sample Exam Problem 6 - Combined Cycles

The Combined Cycles topic accounts for 5 problems on the PE Exam

Given the diagram below for a Rankine cycle, determine the value for W_turbine out. Assume the turbine is 75% efficient.



(A) 710 KW
(B) 830 KW
(C) 990 KW
(D) 1,090 KW


See the Sample Exam for the solution.

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