An evaluation method is developed for single blow experiments with liquids on heat exchangers. The method is based on the unity Mach number dispersion model. The evaluation of one experiment yields merely one equation for the two unknowns, the number of transfer units and the dispersive Peclet number. Calculations on an example confirm that one single blow test alone cannot provide reliable values of the unknowns. A second test with a liquid of differing heat capacity is required, or a tracer experiment for the measurement of the Peclet number. A modified method is developed for gases. One experiment yields the effective number of transfer units and approximate values of the two unknowns. The numerical evaluation of calculated experiments demonstrates the applicability of the evaluation methods.

The recently developed special unity Mach number dispersion model prescribes the corrections to heat transfer coefficients which are simple functions of the dispersive Peclet numbers. They can be determined through the residence time measurements. An evaluation method is described in which the measured input and response concentration profiles are numerically Laplace transformed and evaluated in the frequency domain. A characteristic mean Peclet number is defined. The method is also applied to the parabolic dispersion model and the cascade model. A calculated example of a tube bundle with maldistribution and backflow demonstrates the suitability of the evaluation method.

An evaluation method is developed for temperature oscillation experiments in heat exchangers. The unity Mach number dispersion model is applied. For the consideration of lateral wall heat conduction an effective wall thickness is introduced together with a wall heat transfer coefficient. The evaluation method may also be applied to single blow experiments with pulse signals. A sensitivity analysis describes and discusses the accuracy of different evaluation procedures.

A significant threat to critical infrastructure of computer systems has a destructive impact caused by infrasound waves. It is shown that the known infrasound generations are based on using the following devices: a Helmholtz Resonator, Generation by using a Pulsating Sphere such as Monopolies, Rotor-type Radiator, Resonating Cylinder, VLF Speaker, Method of Paired Ultrasound Radiator, and airscrew. Research of these devices was made in this paper by revealing their characteristics, main advantages and disadvantages. A directional pattern of infrasound radiation and a graph of dependence of infrasound radiation from the consumed power was constructed. Also, during the analysis of these devices, there was proven a set of basic parameters, the values of which make it possible to characterize their structural and operational characteristics. Then approximate values of the proposed parameters of each those considered devices, were calculated. A new method was developed for evaluating the effectiveness of infrasound generation devices based on the definition of the integral efficiency index, which is calculated using the designed parameters. An example of practical application of the derived method, was shown. The use of the method makes it possible, taking into account the conditions and requirements of the infrasound generation devices construction, to choose from them the most efficient one.

The impact of civil engineering course education on civil engineers is profound and crucial. Due to the hierarchical and ambiguous nature of quality assessment for flipped classroom teaching, there is an urgent demand for a rational and effective approach to conduct such assessments. This would enable the targeted formulation of instructional improvement methods based on assessment outcomes, ultimately elevating the quality of pedagogy. This study combines the analytic hierarchy process and fuzzy evaluation method. The fuzzy evaluation method is utilized to identify four primary evaluation factor sets, fourteen secondary judgment factor sets, and five evaluation outcome sets, with subsequent quantification of the assessment results. The analytic hierarchy process is employed to ascertain the weight coefficients of the evaluation factors. The comprehensive assessment model for flipped classroom teaching quality is established. The assessment results indicate that the overall quality of flipped classroom teaching in the civil engineering major at Anhui University of Science and Technology, conducted through the platform of Superstar Learning Hub, falls within the ‘Good’ category. The fuzzy comprehensive evaluation score for extracurricular learning quality is the lowest, and the weight proportion attributed to flipped classroom infrastructure is the highest. Consequently, several targeted improvement measures are proposed to enhance the quality of flipped classroom teaching.