Course detail
Compressors, Fans and Refrigerating Plants
FSI-LOS Acad. year: 2018/2019 Summer semester
The course is concerned with following topics:Positiv displacement compressors, their application in air conditioning and refrigerating equipments. Mechanical refrigerating systems, their application individual or in air conditioning equipments. Fans as a part of ventilation and air conditioning equipments. The course is devoted to designers and operators of this equipments. Following the previous theoretical courses, basics of machine design, operating parameters calculation and application is discuussed.
Language of instruction
Czech
Number of ECTS credits
5
Supervisor
Department
Learning outcomes of the course unit
Students will acquire basic technical knowledge of compressors, fans and refrigerating systems. Knowledge of design of this equipments. Ability to judge the availability of designed or mounted devices from technical, economical and ecological viewpoints.
Prerequisites
Thermodynamics of gases and vapours, thermodynamic cycles, thermofluid mechanics, heat transfer.
Planned learning activities and teaching methods
The course is taught through lectures explaining the basic principles and theory of the discipline. Exercises are focused on practical topics presented in lectures.
Assesment methods and criteria linked to learning outcomes
The exam is written and oral. The written part includes computational task of the two main chapters of the subject (compressors, refrigeration equipment, ventilators)- the need to pocket calculators. Condition for the continuation in the oral part is the solution of computational task at least in the range of 50%. The oral part consists of questions from the remaining chapter.
Aims
Students acquire basic knowledge of machines ensuring gas and vapour distribution and circulation in power engineering, ventilation, refrigeration.
Specification of controlled education, way of implementation and compensation for absences
Attendance at seminars is required. Absence from seminars can be compensated for via make-up project.
The study programmes with the given course
Programme M2I-P: Mechanical Engineering, Master's
branch M-ENI: Power Engineering, compulsory-optional
Programme M2I-P: Mechanical Engineering, Master's
branch M-FLI: Fluid Engineering, compulsory-optional
Programme M2I-P: Mechanical Engineering, Master's
branch M-TEP: Environmental Engineering, compulsory
Type of course unit
Lecture
26 hours, optionally
Teacher / Lecturer
Syllabus
I.Compressors. Performance of positive displacement compressor. Reciprocating compressors.
Rotary and special positive displacement compressors.
Compressor capacity control. Accessories. Compressor stations.
II.Mechanical refrigerating systems. Vapour compression cycle (simple- and multiple-stage)
Absorption refrigeration
Ejector refrigeration
Air-cycle refrigeration.Thermoelectric cooling.
Refrigerating system control, automatics. Indirect refrigerating systems.
III.Fans. Types, principal parts, technical parameters. Dimensionless coefficients.
Centrifugal fans.
Normal axial-flow fans.
Constant-pressure, meridionally accelerated, crossflow fans.
Operating behaviour of a fan. Performance of fans connected to any duct system. Experimental testing of fans.
Exercise
26 hours, compulsory
Teacher / Lecturer
Syllabus
Volumetric and energy design of reciprocating air compressor.
Multistage compressor design, intercoolers.
Calculation of air receiver, reducer, safety valve.
Calculation of simple stage vapour compression cycle.
Calculation of two stage vapour compression cycle.
Calculation of absorption refrigeration cycle.
Calculation of ejector refrigeration cycle.
Calculation of thermoelectric cooling system.
Calculation of air-cycle refrigeration system.
Calculation of main dimensions of centrifugal fan and spiral housing.
Calculation of main dimension of normal axial-flow fan.
Calculation of main dimension of constant-pressure fan.
Two fans working together, effect of diameter and speed changes – calculation of resultant characteristics.