Study on thermal performance of a PCM enhanced hydronic radiant floor heating system

Abstract Radiant floor systems enhanced with Phase Change Materials (PCMs) could achieve significant energy savings while improving the thermal comfort of occupants in lightweight buildings. Effective integration of PCMs typically requires customised solutions based on a comprehensive analysis due to their complex nature. The objective of the present study is the experimental and numerical investigation of a hydronic radiant floor heating system integrated with macroencapsulated PCM. Experimental tests were carried out on a laboratory-scale by the University of Ferrara, Italy, within the H2020 European project IDEAS. A 2D model was then implemented in COMSOL Multiphysics and calibrated in steady as well as in transient state according to the experimental tests. The behaviour of the system, including temperature distribution and heat flux, were analysed under different conditions. The impact of using dry and wet sand, as well as the effect of the position of PCM – above or under heating pipes – on thermal performance, were investigated. Results showed that the use of high thermal conduction in mortar increases much faster the overall performance of the PCM integrated underfloor heating system. Furthermore, the coupling technology with PCM containers installed under piping significantly enhances the positive effect of wet sand

TEMPERATURE PROFILES IN GROUND HEAT EXCHANGERS

A mathematical model of a ground heat exchanger cooperating with a heat pump was presented. The model is based on a one-dimensional heat conduction equation with an internal heat source. On the basis of the solutions to the model equations, both the temperature distribution of different types of ground at different times of year as well as the time courses of temperature at different depths are shown. Calculations based on the presented model can be useful for the simulation and design of this apparatus

Heat conduction in the ground under natural conditions and with heat exchanger installed

The results of calculations of the heat transfer in a horizontal ground heat exchanger are presented. The applied model is based on a one-dimensional equation of the transient heat conduction with an internal heat source. The model was correctly verified by comparison of computational results and experimental measurements presented in literature. Thermal calculations concerning heat transfer in the ground under natural conditions are also presented

Modelling of Heat Transfer in Ground Heat Exchangers

The results of the numerical simulation of heat conduction in ground with a horizontal, tubular (parallel pipes) heat exchanger installed are presented in this paper. On the basis of analysis of courses of temperature isolines in the ground, a simplified mathematical heat transfer model in a horizontal ground exchanger was developed. The ground thermal diffusivity was assumed to be a variable of location. On the basis of the model, the temperature profiles in the ground with a heat exchanger installed were determined

Modelling of Heat Transfer in Ground Heat Exchangers

The results of the numerical simulation of heat conduction in ground with a horizontal, tubular (parallel pipes) heat exchanger installed are presented in this paper. On the basis of analysis of courses of temperature isolines in the ground, a simplified mathematical heat transfer model in a horizontal ground exchanger was developed. The ground thermal diffusivity was assumed to be a variable of location. On the basis of the model, the temperature profiles in the ground with a heat exchanger installed were determined

A Heat Pump-Based Multi-source Renewable Energy System for the Building Air Conditioning: The IDEAS Project Experience

The current paper presents the state-of-the-art of the ongoing IDEAS research project, funded under the Horizon 2020 EU framework programme. The project involves fourteen partners from six European countries and proposes a multi-source cost-effective renewable energy system for the decarbonisation of the building envelope. The system features a radiant floor fed by a heat pump for the building thermal management. The heat pump can exploit sun, air, and/or ground as thermal sources through the use of photovoltaic/thermal solar panels, air heat exchangers, and shallow ground flat-panel heat exchangers. Thermal energy storage is achieved by means of phase change materials spread along several system components, such as: radiant floor to increase its thermal inertia, solar panels for cooling purposes, ground to enhance soil thermal capacity. Within the project framework, a small- scale building, featuring a plethora of sensors for test purposes, and two large-scale buildings are meant to be equipped with the renewable energy system proposed. The small- scale building is currently in operation, and the first results are discussed in the present work. Preliminary data suggest that while multi-source systems coupled with heat pumps are particularly effective, it is complex to obtain suitable thermal energy storages on urban scale

Heat Transfer Model to Predict Temperature Distribution in the Ground

Knowledge of the temperature of the ground in time and space as well as its thermal properties gives basic information about physical phenomena concerning the transfer and accumulation of heat in the ground. It can be also used for evaluation of the heating possibilities of heat pumps; to proper design the size of the ground exchangers and the depth, at which they should be installed. For this purpose, a mathematical model based on the heat balance equation on the ground surface was developed. The basis of the model is the Carslaw-Jaeger equation regarding the temperature profile in the ground. The model was verified using experimental results for two different locations (different climatic conditions, moderate and arid climate)—the standard deviation is equal 0.62 K and 0.92 K, respectively. In this work, the impact of several parameters on the ground temperature profiles and thermal fluxes was determined. It was found that among the examined parameters the amplitude of the daily average solar radiation flux strongly effects on the total amount of heat transferred between the ground and the environment during the year, wherein the other parameters have a negligible effect

An analysis of therapeutic needs and frequency of the use of physiotherapeutic support by pregnant women

Wstęp: Ciąża jest okresem fizjologicznych przemian, w wyniku których dochodzi do wystąpienia wielu dolegliwości. Wbrew utartej opinii przebieg ciąży może być pozbawiony bólu. Aktualna fizjoterapia jest w stanie zaoferować cały szereg efektywnych rozwiązań, które łagodzą różne objawy bólowe.Cel pracy: Celem pracy była analiza potrzeb terapeutycznych ciężarnych oraz próba uzyskania informacji dotyczących częstości korzystania i powodów niekorzystania z usług fizjoterapeutycznych w obszarze łagodzenia dolegliwości okresu ciąży, przygotowania do porodu, profilaktyki powikłań.Materiał i metody: W badaniu wzięło udział 300 kobiet, do analizy zakwalifikowano 270 ankietowanych w okresie połogu. Zastosowano autorski kwestionariusz ankiety, ilość pytań wahała się od 30 do 39 w zależności od odpowiedzi. Badanie było prowadzone od lutego do kwietnia 2021 roku, na platformie Facebook - grupach zrzeszających młode mamy. Udział był anonimowy oraz dobrowolny.Wyniki: Najczęstszą dolegliwością w okresie ciąży był objaw zgagi, wystąpił u 78,9% oraz ból odcinka lędźwiowego kręgosłupa obecny u 78,1% ankietowanych. Zaledwie 24,8% ciężarnych odbyło konsultację u fizjoterapeuty. Z wizyt ukierunkowanych na łagodzenie dolegliwości skorzystało 24,8%, z przygotowania do porodu tylko 10,7%, a profilaktyki powikłań jedynie 7,8% respondentek. Wśród niekorzystających, aż 43,3% respondentek nie wiedziało, że fizjoterapeuta mógł im pomóc w złagodzeniu dolegliwości, 39% w przygotowaniu do porodu i 37% w profilaktyce powikłań.Wnioski: Niewiele ciężarnych korzysta z fizjoterapii. Najczęstszym powodem wizyt jest łagodzenie dolegliwości okresu ciąży, natomiast główną przyczyną niekorzystania z fizjoterapii jest brak wiedzy o takiej możliwości. Potrzebne jest dalsze edukowanie społeczeństwa o roli zawodu fizjoterapeuty w aktywnej opiece nad ciężarną.Introduction: Pregnancy is a period of physiological changes that can result in numerous disorders. Contrary to popular belief, pregnancy can be pain-free. Current physiotherapy offers a whole range of effective solutions to alleviate various pain symptoms.Aim of the study: An analysis of the therapeutic needs of pregnant women and obtaining data on the frequency of the use of physiotherapy, and the reasons behind not using services providing alleviation of pregnancy-related ailments, preparation for delivery or preventing complications.Material and methods: The study involved 300 women; 270 postpartum respondents were qualified for analysis. In an authorial survey, the number of questions ranged from 30 to 39 depending on the answers. The study was conducted from February to April 2021 via Facebook groups for young mothers. Participation was anonymous and voluntary.Results: The most common pregnancy-related ailments was heartburn (78.9%) and lumbar back pain (78.1%). Only 24.8% of the pregnant women consulted a physiotherapist; 24.8% of the visits aimed at alleviating discomfort; 10.7% of them - at preparing for labour and 7.8% - at preventing complications. The non-users responded that they were unaware that physiotherapy is helpful in in alleviating discomfort (43.3%), in preparation for delivery (39%) and in preventing complications (37%).Conclusions: Few pregnant women use physiotherapy. The main reason for that is being unaware of such possibility. The most common incentive to use it is alleviation of ailments. Further education concerning the role of physiotherapist in pregnancy is needed

Physiotherapy in a scoliotic posture with asymmetry of movements in temporomandibular joints - case study

Wstęp: Wiek rozwojowy jest czasem, w którym najczęściej dochodzi do różnych odchyleń w postawie ciała. Postawa skoliotyczna jest pierwszym etapem każdej rozwijającej się skoliozy, zaliczanej do najczęściej występujących ortopedycznych chorób u dzieci oraz młodzieży. W kontroli postawy swój udział ma układ stomatognatyczny, do którego zalicza się stawy skroniowo-żuchwowe.Cel pracy: Przedstawienie pacjentki z postawą skoliotyczną oraz asymetrią ruchów w stawach skroniowo-żuchwowych. Ocena postępu jej rehabilitacji za pomocą komputerowego badania postawy ciała. Materiał i metody: Materiał stanowi dokumentacja medyczna oraz wyniki komputerowego badania postawy ciała trzynastoletniej dziewczynki z cechami postawy skoliotycznej do 10 stopni, asymetrią ruchów w stawach skroniowo-żuchwowych oraz wadą zgryzu - tyłozgryz. W badaniu pacjentki przeprowadzono wywiad, kliniczną ocenę postawy oraz komputerowe badanie postawy ciała. Użyto aparatury, która swoje działanie opiera na metodzie fotogrametrycznej oraz efekcie mory projekcyjnej. W trakcie badania wykonana została komputerowa fotografia (przy użyciu kamery wideo). Za pomocą specjalnego systemu optycznego wyznaczony został trójwymiarowy obraz pleców, a komputer dokonał analizy parametrów w płaszczyźnie zarówno strzałkowej jak i czołowej.Wyniki: Zaobserwowano wyrównanie asymetrii w ruchach stawów skroniowo-żuchwowych oraz odnotowano poprawę w niektórych parametrach w komputerowym badaniu postawy ciała. Podsumowanie i wnioski: Prowadzona w odpowiedni sposób rehabilitacja, a także stosowanie się do zaleceń przez pacjentkę i jej rodziców wpłynęło na poprawę parametrów w badaniu komputerowym oraz badaniu klinicznym.Introduction: The developmental period is the time, in which the most common deviations occur in the posture of the body. The scoliotic posture is the first stage of every developing scoliosis, one of the most common orthopedic diseases in children and adolescents. The stomatognathic system, which includes temporomandibular joints, contributes to control the posture.Aim of the study: Presentation of case - the girl with a scoliotic posture and asymmetry of movements in the temporomandibular joints. Evaluation of the progress of the rehabilitation by means of a computer examination of body posture.Material and methods: The materials are medical documentation and the results of a computer body posture examination of thirteen-year-old girl with scoliotic posture, asymmetry of movements in the temporomandibular joints and malocclusion - posterior bite. The patient's examination included an interview, a clinical assessment of the posture of her body and a computerized examination of body posture. Equipment was used, which operates based on the photogrammetric method and the effect of the projection moiré. During the examination, a computer photograph was made (using a video camera). Using a special optical system, a three-dimensional image of the back was determined, and the computer analyzed parameters in both sagittal and frontal planes.Results: Equalization of asymmetry in temporomandibular joint movements was observed as well as an improvement in some parameters in the computerized postural examination.Summary and conclusions: Rehabilitation carried out in an appropriate methodology, as well as adherence to recommendations by the patient and her parents resulted in improved parameters in the computer examination and clinical examination

Study of temperature distribution in the ground

Knowledge of the temperature distribution in subsurface layers of the ground is important in thedesign, modelling and exploitation of ground heat exchangers. In this work a mathematical model ofheat transfer in the ground is presented. The model is based on the solution of the equation of transientheat transfer in a semi-infinite medium. In the boundary condition on the surface of the groundradiation fluxes (short- and long-wave), convective heat flux and evaporative heat flux are taken intoaccount. Based on the developed model, calculations were carried out to determine the impact ofclimatic conditions and the physical properties of the ground on the parameters of the Carslaw-Jeagerequation. Example results of calculated yearly courses of the daily average temperature of the surfaceof the ground and the amount of particular heat fluxes on the ground surface are presented. Thecompatibility of ground temperature measurements at different depths with the results obtained fromthe Carslaw–Jaeger equation is evaluated. It was found thatthe temperature distribution in the groundand its variability in time can be calculated with good accuracy