Critical rationalism faces difficulty in Karl Popper’s Socratic formulation: “I may be wrong, and you may be right, and by an effort, we may find the truth.” But the Socratic elenchus, using refutations, can only give us negative knowledge of general principles, which is not the wisdom we seek. Affirmatively, we can only find a collection of opinions to be coherent, which is one of many. Francis Bacon proposed an improved elenchus to find general truths. You must take up a limited topic to study, then cross-examine your evidence for and against its apparent nature. Experiments contrary to evidence and presumed knowledge are entered as self-contradictions in tables of opposition recorded in an “EXPERIMENTAL and natural history.” Such an account highlights a challenging puzzle if the account is to be made coherent. With enough problematized evidence, a coherent reading, or a solution of the puzzle, will be unique. Being both coherent and unique, it will be the truth about that limited reality being investigated. Unlike the method of hypothesis (“Anticipating Nature”), deciphering a coherent model is “Interpreting Nature,” allowing us to find a general truth on a limited topic. Isaac Newton achieved great success using Robert Boyle’s mechanistic version of this method. Using the “EXPERIMENTAL philosophy,” he discovered general principles of optics and astronomy.

The thermal balance analysis is a useful method to determine energy distribution and efficiency of internal combustion (IC) engines. In engines cooling concepts, estimation of heat transfer to brake power ratio, as one of the most significant performance characteristics, is highly demanded. In this paper, investigation of energy balance and derivation of specific heat rejection is carried out EXPERIMENTALly and numerically. Experiments are carried out on an air-cooled, single cylinder, four-stroke gasoline IC engine. The engine is simulated numerically and after validation with EXPERIMENTAL data, the code is run to find out total and instantaneous thermal balance of engine. Results indicate that about onethird of fuel energy is converted to brake power and major part of energy is dissipated through exhaust and heat transfer. EXPERIMENTAL and numerical results show that by increasing engine speed, heat transfer to brake power ratio decreases. It is also observed that increasing engine speed leads to increase of exhaust power to brake power ratio. Finally two CORRELATIONs for estimation of heat transfer and exhaust power to brake power ratios are obtained.

Liquid paraffin as a coolant fluid can be applied in electronic devices as a result to its suitable capabilities such as electrical insulating, high heat capacity, chemical and thermal stability, and high boiling point. However, the poor thermal conductivity of paraffin has been confined its thermal cooling application. Addition of high conductor nanoparticles to paraffin can fix this drawback properly. In this article, the influence of the nanoparticles on the thermal conductivity of base material was assessed. Temperature (20-50° C) and volume fractions (0-3%) effect on the thermal conductivity of paraffin/alumina nanofluids have been considered. Nanofluid samples were prepared applying the two-step method. The thermal conductivity was measured by a KD2 pro instrument. The results indicated the thermal conductivity augments smoothly with an increase in volume fraction of nanoparticles as well as temperature. Moreover, it observed that for nanofluids with more volume-fraction the temperature affection is more remarkable. Thermal conductivity enhancement (TCE) and effective thermal conductivity (ETC) of the nanofluid was calculated and new CORRELATIONs were reported to predict the values of them based on the volume fraction of nanoparticles and temperature of nanofluid accurately.

Currently, composite structures have many applications in various industries including aerospace, automotive, marine, and petrochemicals. In most of these applications, the structure is under dynamic and static loads and it can cause buckling, vibration, and fatigue. Therefore, the static and dynamic analysis of these structures is essential in order to understand their characteristics, including buckling, natural frequency, and the shape of vibrating modes. One of the most important non-destructive methods for predicting the buckling load of the structure is the vibrational CORRELATION technique (VCT), which is based on frequency variations with the axial load. In this study, an EXPERIMENTAL study of the buckling load of composite sandwich plates with lozenge core has been investigated. The hand lay-up method has been used for fabrication of the composite sandwich plates. One of the specimens was used for the modal test. In order to verify the results of the VCT, the buckling load of four specimens was calculated by the EXPERIMENTAL buckling test. The error of VCT was 2. 1 %. Hence, the efficiency of the VCT for composite sandwich plates with lattice core was confirmed. Also, by investigating the effect of applied load percentage on the accuracy of the VCT, it was found that for the applied load of more than 63% of the buckling load, the accuracy of prediction of the vibrational CORRELATION technique is acceptable.

Air conditioning systems are used in industries and residential environments with the aim of improving environmental conditions and creating a comfortable temperature for users. Considering the production of sound and vibration in most of its components, the lack of control of the production sound level always exposes the users to unwanted sound, which in addition to hearing complications, also causes fatigue and dissatisfaction with the environmental conditions. . Compressors are one of the most important sources of sound production in air conditioning systems, and screw compressors are one of the most widely used in air conditioning industries. Therefore, the compressor shell should be designed to minimize the transmission of sound from inside to outside. Since the maximum working temperature of compressors is up to 80 degrees Celsius, therefore, in this research, an acoustic test was performed on a sample of a screw compressor shell in two modes of ambient temperature and maximum working temperature inside the acoustic room, and the effect of temperature increase on the sound pressure level. transferred from the shell to the external environment is discussed. Finally, based on the frequency analysis performed in two conditions of ambient temperature and maximum working temperature and comparing the amount of sound transmitted to the environment at different frequencies, practical solutions to reduce the amount of transmitted sound pressure have been presented.