Vladimir Ryndin, Amangeldy Karmanov, Akmaral Kinzhibekova, Rizagul Dyussova, Gulnara Abdullina
{"title":"用Mathcad验证压缩波非定常流动热力学第一定律","authors":"Vladimir Ryndin, Amangeldy Karmanov, Akmaral Kinzhibekova, Rizagul Dyussova, Gulnara Abdullina","doi":"10.1615/heattransres.2023051072","DOIUrl":null,"url":null,"abstract":"Classical thermodynamics traditionally overlooks the role of quantities dependent on spatial coordinates and time, especially in the context of unsteady flows. This research introduces the first law of thermodynamics (FLT) tailored for non-stationary flow, distinguishing itself with the inclusion of terms bearing partial derivatives of pressure, p(x, t), concerning coordinates and time (–υ(∂р/∂х)dx; –υ(∂р/∂t)dt). By employing this novel approach, the derived equations are validated using a centred compression wave as a representative non-stationary flow case study. A methodology is also presented for experimentally quantifying hydrodynamic energy losses in the intake and exhaust systems of internal combustion engines. Central to the exploration is the calculation of pressure forces' work –υ(∂р/∂х)dx and –υ(∂р/∂t)dt) in the FLT equation for non-stationary flows, particularly their applicability to a centred compression wave. Moreover, a distinct procedure for discerning friction work in non-stationary flow is delineated. The research methods encompass both analytical derivation and numerical simulations leveraging Mathcad software. The bespoke Mathcad program crafted for this study can graphically represent multiple flow parameters as functions of time, proving invaluable for comprehending compression wave dynamics and evaluating friction work in diverse non-steady flows. Ultimately, the incorporation of energy equations tailored for non-stationary flows into classical thermodynamics paves the way for a more comprehensive understanding and application of thermodynamics to intricate flow scenarios.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Validating the First Law of Thermodynamics for Unsteady Flow in a Compression Wave Using Mathcad\",\"authors\":\"Vladimir Ryndin, Amangeldy Karmanov, Akmaral Kinzhibekova, Rizagul Dyussova, Gulnara Abdullina\",\"doi\":\"10.1615/heattransres.2023051072\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Classical thermodynamics traditionally overlooks the role of quantities dependent on spatial coordinates and time, especially in the context of unsteady flows. This research introduces the first law of thermodynamics (FLT) tailored for non-stationary flow, distinguishing itself with the inclusion of terms bearing partial derivatives of pressure, p(x, t), concerning coordinates and time (–υ(∂р/∂х)dx; –υ(∂р/∂t)dt). By employing this novel approach, the derived equations are validated using a centred compression wave as a representative non-stationary flow case study. A methodology is also presented for experimentally quantifying hydrodynamic energy losses in the intake and exhaust systems of internal combustion engines. Central to the exploration is the calculation of pressure forces' work –υ(∂р/∂х)dx and –υ(∂р/∂t)dt) in the FLT equation for non-stationary flows, particularly their applicability to a centred compression wave. Moreover, a distinct procedure for discerning friction work in non-stationary flow is delineated. The research methods encompass both analytical derivation and numerical simulations leveraging Mathcad software. The bespoke Mathcad program crafted for this study can graphically represent multiple flow parameters as functions of time, proving invaluable for comprehending compression wave dynamics and evaluating friction work in diverse non-steady flows. Ultimately, the incorporation of energy equations tailored for non-stationary flows into classical thermodynamics paves the way for a more comprehensive understanding and application of thermodynamics to intricate flow scenarios.\",\"PeriodicalId\":50408,\"journal\":{\"name\":\"Heat Transfer Research\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.7000,\"publicationDate\":\"2023-11-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Heat Transfer Research\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.1615/heattransres.2023051072\",\"RegionNum\":4,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"THERMODYNAMICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Heat Transfer Research","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1615/heattransres.2023051072","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"THERMODYNAMICS","Score":null,"Total":0}
Validating the First Law of Thermodynamics for Unsteady Flow in a Compression Wave Using Mathcad
Classical thermodynamics traditionally overlooks the role of quantities dependent on spatial coordinates and time, especially in the context of unsteady flows. This research introduces the first law of thermodynamics (FLT) tailored for non-stationary flow, distinguishing itself with the inclusion of terms bearing partial derivatives of pressure, p(x, t), concerning coordinates and time (–υ(∂р/∂х)dx; –υ(∂р/∂t)dt). By employing this novel approach, the derived equations are validated using a centred compression wave as a representative non-stationary flow case study. A methodology is also presented for experimentally quantifying hydrodynamic energy losses in the intake and exhaust systems of internal combustion engines. Central to the exploration is the calculation of pressure forces' work –υ(∂р/∂х)dx and –υ(∂р/∂t)dt) in the FLT equation for non-stationary flows, particularly their applicability to a centred compression wave. Moreover, a distinct procedure for discerning friction work in non-stationary flow is delineated. The research methods encompass both analytical derivation and numerical simulations leveraging Mathcad software. The bespoke Mathcad program crafted for this study can graphically represent multiple flow parameters as functions of time, proving invaluable for comprehending compression wave dynamics and evaluating friction work in diverse non-steady flows. Ultimately, the incorporation of energy equations tailored for non-stationary flows into classical thermodynamics paves the way for a more comprehensive understanding and application of thermodynamics to intricate flow scenarios.
期刊介绍:
Heat Transfer Research (ISSN1064-2285) presents archived theoretical, applied, and experimental papers selected globally. Selected papers from technical conference proceedings and academic laboratory reports are also published. Papers are selected and reviewed by a group of expert associate editors, guided by a distinguished advisory board, and represent the best of current work in the field. Heat Transfer Research is published under an exclusive license to Begell House, Inc., in full compliance with the International Copyright Convention. Subjects covered in Heat Transfer Research encompass the entire field of heat transfer and relevant areas of fluid dynamics, including conduction, convection and radiation, phase change phenomena including boiling and solidification, heat exchanger design and testing, heat transfer in nuclear reactors, mass transfer, geothermal heat recovery, multi-scale heat transfer, heat and mass transfer in alternative energy systems, and thermophysical properties of materials.